Key feagri iversen

Interactieve sleutel (Fægri & Iversen) [te verifiëren]

Tabel-overzicht

Brontekst (OCR)

WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Master key A2 Grains with air-sacks TableA A, Grains without air-sacks. B₂ Composite grains B, Grains single. Table B C, Grains polyedric. C₂ Grains bilateral. Table C Table D C₁ Grains isodiametric or one axis longer/shorter, rarely heteropolar.. 00 D2 Grains subtetrahedral D, Grains rotational Table E Table F Table A. Vesiculate (Pinaceae and Podocarpaceae) сс a , Three meridional, airsack-like crests .Trapa) A₂ One marginal, anular, rudimentary air-sack. Tsuga spp A, Distinct, subglobular or pouch-shaped air-sacks with internal, 3-dimensional reticulum, usually two. B2 Proximal part of the exine ('crest') more than 5μm thick C₂ Body of the grain (excl. air-sacks) 80-100μm. Air-sacks more than semiglobular. Abies C₁ Body of the grain ca. 50 μm. Air-sack semiglobular.....Cedrus B, Proximal part of exine less than 5μm thick. D2 Proximal entry angle of air-sack very blunt; no obvious constriction, between air-sack and bodyofthe grain E2 Gradual transition between structure of the air-sack and that of the wall of the body of the grain. Colpus membrane smooth.. Picea 241TEXTBOOK OF POLLEN ANALYSIS E, Abrupt transition between structure of air-sack and that of the wall of the Q D, Proximal entry angle of air-sack sharp; distinct constriction between air-sack and body of the grain. F2 Body of the grain ca. 50 μm. G₂ Colpus membrane smooth G, Colpus membrane dotted.. .Pinus diploxylon t. .Tsuga mertensiana F, Body of the grain less than 40 μm and/or grain with more than two air-sacks Podocarpaceae Table B. Composite grains 80 Owing tothe greatvariability and mutual similarity of many Ericales pollen types the key does not invariably catch all grains from the taxa indicated. Atypical grains usually end up in one of the collective taxa, especially the Vaccinium type. The 'normal' position of a tetrahedral tetrad is the one in which the polar axis ofone grain is parallel with the optical axis of the microscope (cf. the illustrations). B₂ Tetrad linear Grain with one pore, ca. 3μm wide . . . Typha spp. 88888 COO B, Tetrad irregular. Grain with single pore 6μm wide (Epipactis palustris)or two apertures Orchidaceae Table Bl. Dyads. Table B2. Tetrads Scheuchzeria A₂ Tetrads linear,flat or irregular. Grains reticulate, each with two apertures.. A Tetrads tetrahedral, sometimes irregularly so C, Grains echinate. D2 Tricolporate, furrows broad, not concealed. Aldrovanda 242WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Droseraceae 243 D, Stephanoporate, apertures concealed. . C Grains psilate, inaperturate. Exine extremely thin, normally not preserved/recognized in deposits.. .. Juncaceae C, Grains scabrate or verrucate. E2 Triporate, pores with vestibulum. Grains loosely connected. Cf. Table F15: Triporate... .Onagraceae E₁ Tricolpate/tricolporate. Pyrolaceae, Ericaceae (cf. Oldfield, 1959) F₂ Tetrads open, usually with a gap in the middle; grains united by a peripolar circular region... Chimaphila F, Tetrads not open; grains united by theirproximalfaces G₂ Tetrads loose, often irregular or flattened. Edge offurrows irregular, costae absent or indistinct. Frustillate-verrucate Calluna G₁ Tetrads compact, Furrows regular, costaeusuallydistinct. H, Tetrads globular. Arctostaphylos. I₂ Interior walls densely perforate. .A. alpina I, Interior walls with few perforations. . . . A. uva-ursi H, Tetrads subtriangular. Colpi long withdistinct costae.Tetrad less than 35 μm. . Cassiope H, Tetrads subglobular-subtriangular J Grains usually in normal position. Interior walls thick and straight, Y figure rectilinear... K2 Interior wallsdistinctly thicker than the exteriorones. Costae indistinct. Colpi with transverse cracks.. Empetrum nigrum K, Interior and exterior walls equally thick. Costae heavy. Colpi without traverse cracks . . .Ledum J₁ Grains usually not in a strictly normal position. Yfigure ofinner walls not rectilinear. L2 Colpi very short. Costae indistinct. . . . MonesesTEXTBOOK OF POLLEN ANALYSIS L₁ Colpi long, usually with margo. Vaccinium group. M2 Interiorwalls densely perforate. .. M, Interior walls with few or no perforations. N₂ Coarsely verrucate. Incl. Phyllodoce. N, Psilate to irregularly scrabrate-verrucate. Andromeda O Costae absent/indistinct. Erica tetralix t. P₂ Polar index large. Columellae evenly distributed. Exinethick Rhododendron lapponicum t. P Polar index smaller. Exine thinner. Incl. Pyrola spp. . . . Empetrum hermaphroditum O, Costae distinct. Q: Interior walls thicker than the exterior ones. . Loiseleuria QInterior walls not thicker than the exterior ones R₂ Tetrads subglobular. Walls thick . . Chamaedaphne R₁ Tetrads subglobular. Incl. Andromeda, Chamaedaphne, Empetrum hermaphroditum, Erica spp., Phyllodoce, Oxycoccus. Vaccinium t. Table B3. Polyads (A₂ Regularpolyads of 8-16-32 grains.. A Polyads irregular; tetrads usually indistinguishable. Acacia) B2 Loose aggregations... Chimaphila B, Tetrads densely crowded in massulae, usually irregular. C₁₂ Monoporate Orchidaceae C₁ Triaperturate Asclepiadaceae Table C. Polyedric grains Most recent polyedric grains areeasily reduced to the corresponding rotational shape byabstracting prominent apertures, ridges, etc. The empty exines of a few pericolpate grains are polyedric. The stephanocolporate grains of the Viola tricolor group appear polyedric, due to flattening ofthe polar areas. In pre-Quaternary material moreor less distinctly polyedric sporomorphs are found. Some recent cyptogam spores, cysts,etc., would also come in here. 244WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Table D. Bilateral grains Some monocolpate and biporate grains are faintly bilateral or pear-shaped (heteropolar). They are found in Table F. A₂ With more than one aperture. B₂ Tetra-aperturate, reticulate .Impatiens B₁ Bi-tetra-aperturate pores aggregated. Psilate Myriophyllum alterniflorum A₁ With one or no aperture. C2 With columellae. Grain reticulate. 00 D2 Grain slightly bent. Intectate at both ends. Columellae distinctly separate . .Ruppia D, Grain not bent. Heterobrochate, semitectate, columellaeforming muri. Liliaceae (cf. Table F4). C₁ No columellae. Pteridophyte spores. E2 Perine loose, crested or folded, not echinate but in some spores spinulose. F2 Perine saccate. Dryopteris t. F, Perine lophate-cristate. G₂ Crests few, 1-4, long, sometmes as long as thespore Matteuccia t. G₁ Usually more than 4 crests, shorter. H2 Crests with few or no spinules. H, Crests densely spinulose. Woodsia t. E₁ No loose outer perine or, if present, not folded or crested. Asplenium t. 14 Verrucate, sculpturing elements coarse, more than 3 μm high I, Scabrate. J₂ No perine visible Polypodium Athyrium fillix-femina 245246 TEXTBOOK OF POLLEN ANALYSIS J, Perine thin, slightly wrinked Blechnum spicant I₂ Psilate. K2 Wall double with loose outer cover.. K, Wall one-layered or outer cover not loose. .Isoëtes L2 Wall faintly undulate. . . . . . Gymnocarpium dryopteris t. L₁ Wall smooth, structureless. Unidentifiable fern spores that have lost their perispore. I, Echinate. M2 Spines scattered, slender, uniform. M, With spines and (blunt) papillae. N₂ Mainly papillae . . . Cystopteris filix-fragilis N, Sculpturing elements variable Cystopteris spp. Thelypteris palustris Table E. Subtetrahedral grains (spores) A2 With an outer, loose, folded perine, cf. Table D A, No loose perine. Cf. Thesium, Table F19. Matteuccia B, Grain subglobular, exospore thin.. C Spore echinate(-foveolate) Hymenophyllum 人 C, Spore baculate-clavate.. B₂ Spore triangular, semi-lobate. D2 Corners flattened .Osmunda D₁ Corners rounded. E₂ Verrucate .Lycopodium selago E, Scabrate-fimbriate, usually smooth by loss of ornamentation... Cryptogramma PteridiumWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA B, Equatorial limb triangular-subcircular. Polar axis shorter than equatorial diaF, Echinate. meter F4 Foveolate. Selaginella F, Reticulate, muri sharp. Lycopodium s.l. . Ophioglossum G2 Heterobrochate. H₂ 5-6 brochi in median ofdistalface; reticulum sparselydevelopedon proximalface.. . L. annotinum H, Reticulum developed on proximalface, rarely covering morethan halfway in to centre. . L. complanatum t. G₁ Homobrochate, brochi present also on proximal face. I₂ Laesura arms undulating: 10-12 brochi inmedian I₁ Laesura arms straight; 7-9 brochi in median F2 Rugulate. L. clavatum. L. alpinum J₂ Valla narrow, on the distal side only J₁ Valla broad, indistinct pattern also on proximal face. L. inundatum F₁ Verrucate. Botrychium multifidum K3 Verrucae indistinct, exine stains weakly with fuchsin. Polaraxis short. Sphagnum K2 Verrucae baculoid-echinate. K₁ Verrucae rounded, sometimes spinulate. Botrychium... L, Spore more than 54μm diameter. Sculpturing on proximal face less distinct. B. boreale t. L2 Spore 43-58 μm. Sculpturing on proximal face as distinct as on the distal. L₁ Spore smaller than 43 μm. Ophioglossum B. lunaria t. B. virginianum 247248 TEXTBOOK OF POLLEN ANALYSIS Table F. Rotational ellipsoidic (or ovate) grains: main key The left-hand figure gives the polar view, the right-hand one the equatorial, except for B₁, H₁,J, and L₁, which are apolar. The two figures at E, represent twodifferenttypes (ring and spiral). A No distinct aperture. B With meridional groves and ridges. .F1 Polyplicate B, No meridional groves or ridges A2 With one aperture. F2 Inaperturate C, Aperture three-silt.. О C₂ Aperture elongate. F3 Trichotomocolpate C₁ Aperture circular. A More than one aperture. E2 Apertures not fused. G₂ Three furrows . F4 Monocolpate OO F5 Monoporate DO D2 No lacunae or, if present, not in a fixed geometric pattern. F, Withfurrows, no pores or transverseendexinous furrows (colpate) G₁ Two furrows.. F6 Dicolpate о G, More than three furrows. F7 Tricolpate H₂ All furrows meridional. F8 Stephanocolpate H₂ Some or all furrows not meridional. F9 Pericolpate (X) F2 Both furrows and distinct pores or transverse furrows present (colporate). Usually one pore per furrow, occasionally missing; in some taxa more than one pore per furrow (not in our material).WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA оо I, Two furrows 12 Three furrows. I, More than three furrows. J₂ All furrows meridional.. F10 Dicolporate .F11 Tricolporate J₁ Some or all furrows not meridional. . .F13 Pericolporate F₁ Free pores present, no furrows (porate) F12 Stephanocolporate K3 Two pores K₂ Three pores K₁ More than three pores. F14 Diporate .F15 Triporate L₂ Pores confined to a circular (sub-)equatorial belt.. L₁ Pores ± uniformly distributed on the surfaceofthegrain F16 Stephanoporate F17 Periporate E₁ Apertures fused to rings or spirals. D₁ With lacunae in a fixed geometric pattern F18 Syncolpate M2 Lacunae elongate, meridional (pseudocolpi). . . . . F19 Heterocolpate , Lacunae not elongate. F20 Fenestrate 249TEXTBOOK OF POLLEN ANALYSIS Table Fl. Polyplicate (Ephedra) A₂ Groves branched A₁ Groves simple. E. distachya t. B₂ More than 10 groves. C Meridional ridges low, indistinct in polar view. . . E. strobilacea t C, Meridional ridges high, distinct in polar view B, Fewer than 10 groves E. fragilis t. Table F2. Inaperturate E. fragilis t. Many cryptogram spores, cysts, etc., are also inaperturate. They are, on the whole, easilydistinguished from pollen grains by the (absence of) structure ofthe wall. They are not included in the key. A Cavate (verrucate) or echinate. B, Cavate. Grain more than 50μm. B₂ Echinate. Cf. also Lemnaceae, Nymphaea: Table F5, monoporate, and Nuphar, Stratiotes: Table F4, monocolpate Hydrocharis B₁ Verrucate, cf. Plantago, Table F17. A, Scabrate or frustillate. Tsuga C Grain heteropolar, with thin areas (lacunae). Cf. special key. . Cyperaceae C₁ No lacunae or perforations. Populus. D2 Scabrate, with minute dark dots. . . . P. tremula t. D, Frustillate, exine easily broken A2 Psilate/gemmate. E₂ Psilate. .P. balsamifera t. . F2 Grain more than 50 μm. Exine not perforate G₂ Grain ca. 90 μm G₁ Grain 60-85μm. Pseudotsuga Larix F, Grain less than 50 μm. Exine perforate (some areas sometimes not). H₂ Grain ca. 25-30μm. Sculpturing apparently vermiculate. Oneor two ruptured areas Calla H, Grain ca. 15μm, smooth.. E₁ Gemmate .Acorus 250WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA I With a well-marked exitus papilla... Taxodiaceae I, No exitus papilla. J₂ Fossil grains usually two-split. Gemmae scattered, deciduous,rounded, with constricted base, mostly lost in fossil material. Cf. Pedicularis, Table F16 ...Juniperus J, Gemmae rather crowded, size variable, not deciduous. SEM: microbaculate . . . Taxus A₁ Clavate-baculate or reticulate. K2 Grain bilateral, slightly bent. Intectate at ends; columellae distinctlyseparate K₁ Grain rotational. L₂ Isolated clavae/baculae in reticulatepattern L₁ Reticulum distinct. Ruppia M2 Columellae distinct. Callitriche N2 Diameter of lumina subequal to breadth ofmuri Daphne N₁ Diameter oflumina several times the breadth ofmuri.Potamogeton. O2 Columellae widely spaced, mostly confinedtocornersof brochi.. Coleogeton t. O, Columellae denser, also between corners ofbrochi; cf. also Triglochin maritimum. . . Potamogeton t. M, Columellae indistinct. P Diameter of lumina subequal to breadth (indistinctly) duplicolumellate. P, Muri much narrower than width of plcolumellate. .. Table F3. Trichotomocolpate ofmuri. Muri Daphne lumina, simTriglochin Triradiate scars are very common in cryptogam spores (cf. Table E). In angiosperm pollen they are found in some taxa, e.g. in Palmae and Liliaceae, or Annonaceae. In the area none is known, apart from occasional faint traces in somegrains ofTrapa natans. 251 51TEXTBOOK OF POLLEN ANALYSIS Table F4. Monocolpate оо Compare also Table F5, Monoporate, the pore of which may become colpus-likeby collapse ofthe grain A Verrucate. B₂ Verrucae uniform, hollow, multicolumellate. Aperture broad, irregular Sciadopitys B, Verrucal dimorphic, smaller on the proximal side. . .Gagea pratensis t. A, Echinate-baculate with sculpturing elements projecting abovea bottom ofminute, crowded projections . . . C Grains usually prolate. Echinate; spines more than 5μm long. Nuphar C Grains subspherical. Baculate-echinate, large projections less than 5μm long. Aperture sometimes indistinct .Stratiotes A Reticulate (brochi equal to or more than 1 μm). D2 Brochi more than 3μm diameter. E2 Heterobrochate. Margo very broad... . Anthericum E₁ Homobrochate or brochi not falling into discrete size groups. F₂ Muri consisting oftransverse elements. No free columellae in lumina. Margo present.. ... Lilium F₁ Columellae approximately cylindric. Free columellae in some brochi. No margo. Iris pseudacorus t. D, Brochi 1-3 μm diameter. G₂ Furrow extends to the proximal side ofthegrain Muscari G₁ Furrow restricted to the distal side ofthegrain. H, Heterobrochate. Grains long, narrow. Few, large brochi, mostly on the proximal side of the grain. Incl. Ornithogalum, Polygonatum verticillatum.. Scilla t. H, Homobrochate. I, Grain less than 30 μm. Brochi ca. 1 μm; reticulum with gradient towards colpus. Narthecium ossifragum 12 Grain 30-50μm. Margo present. Muri narrow. Incl. Butomus, Veratrum.. .Narcissus 252WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA I, Grain more than 50μm. J₂ Pollen often ruptured with ragged colpus edges. No margo Iris pseudacorus t. J, Margo present. Columellae distinct. .. . Fritillaria 253 A, Microreticulate (brochi less than 1 μm), psilate or scabrate. K₁ Furrow extends to the proximal side ofthe grain. Allium porrum,A.scorodoprasum, A. vineale K₁ Furrow restricted to the distal side of the grain. L2 Grain less than 30μm. M2 Columellae imperceptible. Brochi ca. 1μm M, Columellae distinct. Brochi less than 1 μm L₁ Grain more than 30μm. Narthecium ossifragum Asparagus N, Grain shaped like an orange segment. Allium. O₂ Psilate with minute perforations and columellae. Incl. Allium angulosum, A. montanum, A. paradoxum A. ursinum t. O₁ Foveolate with distinct perforations and columellae. Incl. A. schoenoprasum A. oleraceum t. N₂ Grain curved with thickened ends .....Sisyrhinchium N₁ Grain neither segment-shaped nor curved with thickened ends. 00 P Reticulate, muri broader than width oflumina. Q: Homobrochate... QHeterobrochate... Ornithogalum umbellatum, Tulipa silvestris Smilacina stellata P, Psilate-scabrate, perforate. R, Grain more than 60 μm. Columellae evenly distributed. Colpus edges ragged, almost marginate Brasenia schreberi R₁ Grain less than 50μm. Columellae unevenly distributed. S₂ Columellae distributed in relation to majorperforations. Colpus edges ragged Gagea lutea t. S, Columellae irregularly distributed. Colpus edges straight... Majanthemum bifolium .254 TEXTBOOK OF POLLEN ANALYSIS Table FS. Monoporate A₂ Pore large, diameter more than half that of the grain. B₂ With operculum. Grain verrucate, gemmate, clavate, baculate and/orechinate. Sculptural elements unicolumellate. Grain oblate-subsphaeroidal operEulum Nymphaea B, No operculum. Grain verrucate, projections multicolumellate. Grain subsphaeroidal... . . .Sciadopitys A, Pore smaller, diameter usually much less than half that of thegrain. C₂ With distinct anulus. Grain tectate, psilate, scabrate, verrucate. Cf. special key... Gramineae C₁ No anulus. Cf. Juniperus, Table F2. D, Grains psilate, densely perforate with lacunae, one of which forms a rudimentary pore at broad end of usually pear-shaped grain. Cf. special key.. . Cyperaceae D2 Grain reticulate, heterobrochate. Pore not always distinct. D, Grain echinate, spines ca. 1.5 μm with broad conical base. Poremaybe indistinct. Cf. cysts and other microfossils of unknown origin Table F6. Dicolpate оо Sparganium, Typha spp. Lemnaceae A2 Columellae distinct. Per-reticulate. Margo present A, Columellae indistinct. No margo. B, Per-reticulate. Grain prolate. Tamus Tofieldia B₂ Psilate-rugulate and perforate or occasionally reticulate. Shapeirregularly sphaeroidal... Calla (B, Grain usually two-split, edges ragged. Structure and sculpturing very faint or nil. Cf. Table F18. .. PedicularisWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Table F7. Tricolpate: Main key to subsections A₂ Tectate B, Psilate. B4 Scabrate. B3 Echinate-verrucate. B2 Rugulate-striate. B, Supra-reticulate. A Semitectate or intectate C2 Per-reticulate. C₁ Intectate.. Table F7.1 Table F7.2 Table F7.3 Table F7.4 TableF7.5 Table F7.6 . Table F7.7 The crested grains of Trapa are not included in the keys; cf. Table A. Table F7.1 Tricolpate, psilate TECTUM SOLIDUM TECTUM PERFORATUM Furrow without equatorial constriction.. B, Exine equal to or thicker than 3 μm. Columellae shorter and exine thinner next to furrow (crescentic). Convolvulaceae . . . . C Exine ca. 5μm thick. Columellae branched. Grain 70-100μm. C₁ Exine ca. 3 μm thick. Columellae simple. Grain ca. 30μm. Cuscuta B₂ Exine thinner in middle of intercolpium. Furrow narrow, straight, edges sharp. Grain ca. 20μm. Melampyrum Convolvulus pp. B, Exine equal to or thinner than 2uin. Edge offurrow ragged. D; Exineor thinnerirregularly next-to furrow distributed ., micro E2 Grain globular-prolate. Exine thicker in polar area, without perforations. Columellae present in furrow, grouped...Veronica E, Grain globular-oblate. No polar thickening ofexine. Tectum with perforations. Columellae in furrow, ifpresent, scattered. Spergula s.l. echinate. Columellae distinct and/ 255 A256 TEXTBOOK OF POLLEN ANALYSIS F2 Distinctly micro-echinate. Number of perforations and columellae approximately equal. Columellae in a dense, regular pattern.. S. arvense t. F₁ Not echinate. Perforationsfewer than columellae. Columellae irregularly districted. . . . Spergularia t. D₁ Exines same thickness throughout, ca. 1 μm. Surface smooth G₂ Grains oblate. Polar area small, index below 0.3 H₂ Grain ca. 30 μm. Structure imperceptible. . . . . Myricaria H, Grain 40-50μm. Structure distinct... G, Grains subglobular/prolate, 30-40μm. Surface uniform. Incl. Bartsia. Odontites Rhinanthus t. Euphrasia A Furrow with equatorial constriction. Cf. Table 11.1 I, Furrow with prominent, undulating edges. Special key. I, Furrow edges flat, straight. Rosaceae J₂ Microreticulate. Columellae imperceptible . . . .Saxifraga nivalis t. J, Exine not reticulate. K2 Columellae imperceptible. Exine thin .....Viola palustris t. K, Columellae distinct. L₂ Columellae regularly dispersed. Perforations minute, dense. Lobelia L₁ Columellae irregularly dispersed, minute. Perforations scattered, irregular... Myricaria Table F7.2. Tricolpate, scabrate. A₂ Furrow with equatorial constriction. . B₂ Equatorial limb triangular. Costae colpi distinct. Cornus.. C₂ Grain more than 50 μm, scabrate. Tectum perforate. . C. sanguineus C, Grain less than 25 μm, with scattered microverrucae. Tectum imperforate.. C. suecica B₁ No distinct costae colpi. Columellae crowded, minute MyricariaWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA A, Furrow without equatorial constriction.. D, Endexine very thin. Columellae scattered, their mutual distance much greater than their diameter. Furrow more or less operculate.. D; Endexine distinct. Exine thick, at any rate in the polar area. Saxifraga hirculus t. E, Exine more than 3 μm thick, crescentic. Endexine heavy. Columellae distinct, their mutual distance 1-2 times diameter. Furrowmembrane with columella-like granules. .Valerianella E, Exine thinner except in polar area. F2 Furrow edge ragged, granules at membrane much coarser than columellae. .Aconitum F₁ Furrow sharp, membrane without or with very few granules. . Teucrium D₁ Not so. G₂ Low ridges at base of spinules form a reticuloid pattern. Exine with multiple perforations. Papaver H2 Spinules (scabrae) regularly distributed... H, Spinules distinct, often sub-verrucate. G₁ No ridges between bases of spinules. .P. rhoeast. I Structure and sculpturing veryfine. Grain oblate. . Myricaria I, Structure and sculpturing distinct. P. radicatum t. J₂ Spinules of uniform size, regularly distributed. K2 Spinules distinct. Tectum with numerous, dense perforations.... Anemone t. K₁ Spinules minute. Tectum with few, distinct perforations. Columellae fine, in vermiculoid pattern. Grain less than 25 μm . Calthat. J₁ Spinules irregularly distributed, size variable. L2 Tectum without perforations. Columellae distinct, uniform, rather crowded. Furrow narrow. Quercus L₁ Tectum with perforations, (sub-)verrucate-echinate.Columellae distinct, partly absent below verrucae. Furrow open, membrane granulate. Grains often pericolpate, cf. Table F9. Ranunculus. M, Columellae in open pattern, forming a bright area ('halo') around each spinule. Perforationsfollowthe same pattern . R. acris t. M, Columellae in a denser pattern, haloes less distinct. Perforations more evenly distributed R. flammulat. 257Table F7.3. Tricolpate, echinate TEXTBOOK OF POLLEN ANALYSIS A₂ Grain large, 50μm or more. B Spines prominent, long, widely separated. C Polar area very small. Long spines on shield-shaped verrucae C, Polar area large. Equatorial limb subtriangular. Spines coarse, not on shield-shaped verrucae. Incl. Lonicera caprifolium, L. coerulea . . . Lonicera xylosteum t. B, Spines smaller. Valeriana D2 Exine 5-10μm. Columellae branched. Spines ofdifferent size classes. Furrow short, broad, Cf. Table F15, Triporate. ...Dipsacaceae. E, Structural and sculpturing elements regularly distributed. Exine thickerat poles... Scabiosa E₁ Not so. D, Exine less than 3 μm. Spines of uniform size. Succisa F2 Exine ca. 1 μm. Spines widely separated. Colpus edges protruding F, Exine 2-3 μm thick. Spines crowded Lonicera periclymenum A, Grains smaller. Linnaea G, Spines constricted at base, frequentlyflaccid (bent over at base).. (G, Verrucate/scabrate, not really echinate, Cf. Table F7.2. H, Tectum imperforate.. Table F7.4. Tricolpate, rugulate-striate A, Exine thickness and striation normal-fine. Rubus chamaemorus G₂ Spines conical, low. Tectum thick. Colpi short, indistinct (Fig ).Ambrosia 2.3 ,Xanthium ... . H₂ Tectum perforate, colpus membrane with coarse granules... Ranunculus pp. Quercus) A2 Grain very thick-walled. Striae coarse, multilevelled. Colpi wide.. Erodium 258WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Exine with or without perforations. Edges offurrows undulating, often prominent. Rosaceae, cf. Special key B, Exine perforated. Edge of furrows straight. C C₁ Rugulate-scabrate. Vallae short, in reticuloid pattern.. Oxalis acetosella Lo Distinctly striate. D, Sculpturing fine, striaepredominantly meridional. Grain 30μm ormore. Cf. Menyanthes, Table F11.3... .Acer D2 Direction of striae variable . . E2 Grain smaller than 25 μm. Sculpturingfine E, Grain more than 25 μm. Sculpturing coarse. Incl. Saxifraga adscendens, S. aizoides, S. cotyledon, S. osloensis, S. paniculata, S. tridactylites, S. tricuspidata. . . . . Saxifraga oppositifolia t. , Striation diffuse. Vallae in very low relief. Incl. S. rivularis. Trollius Tricolpate, supra-reticulate Saxifraga cernua t. Table F7.5. A: Furrow without equatorial constriction or poroid area. No costae B2 Meridional limb compressed oval, grain subcylindric, usually prolateperprolate. Furrow narrow, not boat-shaped. Onobrychis type. C₂ All brochi large, ca. 1.5μm. .Onobrychis C, Brochi small, ca. 0.5 μm, or a median field of small brochi in each intercolpium. .. Hedysarum B₁ Meridional limb circular, oval or rhomboidal, not compressed. Furrow boat-shaped, often ruptured. Sect. Stachydeae. Incl. Ajuga, Scutellaria.. Stachys t. A₁ Equatorial part offurrow constricted or ruptured. Costae interrupted atequator D₂ Poroid area large, usually ruptured. Branches ofcostae colpi short. Incl. Ulex, Cytisus... Genista t. D, Poroid area small. Branches of costae colpi long. Hypericum E2 Grain less than 30μm. Columellae in most cases not observable.. E, Grain more than 30 μm. Muri duplicolumellate. Hypericum spp. .H. elodes B, 259TEXTBOOK OF POLLEN ANALYSIS Table F7.6. Tricolpate, per-reticulate A Furrow without equatorial constriction.. B Grain large, more than 50 μm, thick-walled. C Columellae not branched, their heads more or less widened, spinulose Plumbaginaceae C Columellae branched, fused to a reticulum some distance below their heads, forming coarse clavae on top. Cf. Erodium, Table F7.4 B, Grain smaller. HANI Geranium D Grain smaller than 25μm. Brochi uniformly small, less than 1 μm. Columellae not discernible. E₂ Wall less than 1 μm thick.Polar area exine thicker, tectatewithfew perforations ... Chrysosplenium E₁ Wall ca. 1 μm thick. Polar area tectate-perforate, not thickened or reticulate... Saxifraga spp. D, At least some brochi more than 1 μm. F₂ Furrow long G2 Heterobrochate. Margo thin, tectate Salix G, No distinct margo. Columellae very distant, only theirheads joined into a reticulum. H2 Exine rather thick. Reticulum with narrow muri. Furrow without granules or with a delicate structure. Cruciferae H, Muri broad. Furrow with scattered granules Glaucium F, Furrow short. Polar area rather large, index ca. 0.4. I Columellae imperceptible. Furrow broad, with scattered granules... Platanus I, Columellae distinct. Muri simpli- or duplicolumellate. Furrow narrow, without granules. Fraxinus 260WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA A Furrow with equatorial constriction.. At least some brochi more than 1 μm. K2 Polar area tectate, perforate. Margo broad, tectate. L2 Muri broader than columellae, dupli- or triplicolumellate Adoxa L₁ Muri not broader than columellae, simplicolumellate Sambucus K₁ Polar area not tectate. Margo narrow. M2 Polar area small. Index less than 0.4. N₂ Distance between columellae in optical section equal to or greater than their height... O₂ Width of muri much smaller than diameter of lumina Hottonia O, Width of muri approximately equal to diameter of lumina.. . . . . Diappensia N, Distance between columellae smaller than their height... P₂ Columellae cylindric P, Columellae with bulbous head. Sambucus. Verbascum Q Reticulum coarse, ca. 10 equatorial brochi per intercolpium. Free columellae in lumina.. S. ebulus Q₁ Reticulum finer, ca. 20 equatorial brochi perintercolpium. ... .. Sambucus spp. M₁ Polar area large, index more than 0.4. R₂ Muri simplicolumellate, columellae coarse. Size of sculpturing elements decreases near furrow Ligustrum R₁ Some muri duplicolumellate, columellae fine. Size ofsculpturing elements uniform.. Fraxinus J, Brochi less than 1 μm. S2 Endexine heavy, distinctly separate from reticulum. T2 Polar area small, index less than 0.4. Wall ca. 2 μm thick.. Sambucus spp. T, Polar area very small, index ca. 0.05. Wall ca. 1μm thick Limosella S, Endexine thin, not distinctly separate from reticulum. J₂ 261262 TEXTBOOK OF POLLEN ANALYSIS U₂ Costae colpi heavy, usually turning outwards at the equator, Diameter of lumina subequal to breadth of muri. Cf. Table 7.5 Hypericum U, No costae colpi.. V2 Margo distinct, tectate. V₁ Margo indistinct or absent Linaria Hottonia, Samolus Table F7.7. Tricolpate, intectate (clavate) A2 Size of clavae variable. B₂ Intercolpium and polar area with scattered, large,free clavae in addition to many small ones, more or less fused. Furrow not distinct ... Viscum B₁ All clavae free. Small clavae scattered beneath the large ones. Near the furrow there are only small clavae, forming a margo. Cf. Rubus chamaemorus, Table F7.3. . . . Ilex A, Clavae dimorphic or uniform. Linaceae C₂ Clavae dense, almost contiguous, fine, 1-1.5μm, dimorphic, the smaller ones dominant. Incl. L. angustifolium. . .L. usitatissimum t. C Clavaedistinctlyseparate, coarse, longer than 1.5 μm, uniform or dimorphic. Ifdimorphic, both size classes subequally represented. Spinules on top of clavae (SEM), cf. Fig. 13.3.. L. catharticum t. L10pm Table F8. Stephanocolpate L10pm A2 Psilate-scabrate. B₂ Grain large. 4-6 broad furrows B, Grain small. 6-10 narrow furrows. A, Reticulate. Hippuris Galium t. C₂ Polar area large, index higher than 0.6. D2 4furrows. Grain oblate, subrectangular. Supra-reticulate; no columellae discernible in muri... .Impatiens D, Per-reticulate. Columellae distinct in muri. E₂ 5-10 furrows. E, 4 furrows. Muri simpli-duplicolumellate. Primula vulgaris FraxinusWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA C₁ Polar area medium-small, index lower than 0.5. Labiatae pp... 263 F2 Supra-reticulate with free columellae in lumina.. F, Per-reticulate. Columellae restricted to muri. Prunella t. G₂ Muri beaded. . G₁ Muri not beaded. Mentha t. Salvia H₂ Lumina small, thickness of columellae more than width ofmuri Satureja H, Lumina large, thickness of columellae more or less equal to width of muri. Incl. Origanum, Thymus. . Lycopus subt. Table F9. Pericolpate (X) A, Reticulate. B₂ Lumina deep, with free, coarse clavae. 30 short furrows in dodecahedral arrangement . Polygonum amphibium B₁ No free elements in lumina. 4-6 furrows. Cf. Tricolpate, Tables F7.5 and F7.6. A2 Echinate. C₂ Spines slender, regularly distributed. Furrows short, numerous.. Koenigia C₁ Spines small, irregularly distributed. Tectum perforate. Central area of intercolpium with coarse columellae in reticuloid pattern. 12 furrows.. Montia A, Psilate, microechinate, scabrate, verrucate. D3 Psilate with minute, evenly distributed spinules (SEM or careful focusing in ph!). Minute perforations visible in SEM. Some grains with internal transverse furrows. Cf. Table F13 ... Polygonum oxyspermum t. D2 Irregularlydistributed spinules, verrucae or scabrae of varying size.Tectum with perforations (ph, SEM): Papaver, Ranunculaceae. Cf. Table F2. D, Psilate-scabrate with uniform minute spinules and perforations. Spergula arvensisTEXTBOOK OF POLLEN ANALYSIS Table F10. Dicolporate Not known from the area are. Table F11. Tricolporate: main key to subsections Together with tricolpate grains, the tricolporate are the most numerous and also the most troublesome ofthe list. The key presumes very close observation, and even then a certain subjectivity in the perception of morphological features is unavoidable. Some users maydisagree with our treatment ofindividual taxa. In cases ofdoubtwe have tried to cover conflicting opinions by entering the same pollen taxon in different places in the key. Especially, the transition colpate-colpate with equatorial constriction-colporate is not easy to define in categorical terms. Consultation ofTableF7 is recommended ifTable F11 does not lead to a result. A₂ Tectate. B. Psilate or scabrate. B, Echinate.. B₂ Striate or rugulate. B, Foveolate or supra-reticulate Table F11.1 Table F11.2 Table F11.3 Table F11.4 A, Semitectate. Per-reticulate .. Table F11.1. Tricolporate. Psilate-scabrate TECTUM PERFORATUM Table F11.5 TECTUM SOLIDUM A₂ With costae aequatoriales and transversefurrows. B₂ Equatorial limb intersemiangular. Exine more than 4μm thick, crescentic Columellae coarse, branched. Centaurea sect. Cyanus. C Meridionallimb compressed oval. Costae aequatoriales sharply projectingin meridional optical section.. .C. cyanus t. C₁ Meridionallimb oval. Costae aequatoriales less prominent C. montana t. B, Equatorial limb subcircular. Exine thinner, not crescentic. Columellae finer. Costae aequatoriales less prominent. Polygonum aviculare t. + о 264WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA 265 No costae aequatoriales. D₂ Meridional limb compressed oval. E2 Grain distinctly prolate (cf. Cerceau, 1959). . . . } E, Not so distinctly prolate. Umbelliferae F2 Exine more than 3 μm thick. Grain more than 50μm, dimorphic, one type with denser structure. Tectum with scattered perforations. Columellae branched, coarser at poles.. Polygonum bistorta F, Exine thin. G₂ Grain more than 30 μm. Pore edges distinctly protruding. Scabrate, polar area suprareticulate . . . . Anthyllis G, Grain less than 25μm, psilate. D, Meridional limb oval or circular. I2 Exine thicker and columellae coarser at poles. Furrow narrow, slitshaped. Lotus H₂ Intercolpium flattened or concave in polar view J₂ Prolate-apiculate. Pore rectangular. J₁ Subglobular. I₁ Thickness of exine uniform. Furrow not slit-shaped. Pleurospermum Hydrocotyle + K2 With transversefurrow L2 Scabrate. Tectum perforate. Grain 20-35μm Rhus coriaria t. L₁ Psilate. Tectum not perforate. Solanum. M2 Grain more than 20μm. M, Grain smaller than 20μm. K, No transverse furrow. N₂ Pore more than 3 μm, edged by heavy costae. Grain ca. 50μm. Columellae distinct. Nyssa N, Pore smaller. . O₂ Equatorial limb semilobate. Psilate. S. nigrum S. dulcamara Rhamnus frangula . A₁266 TEXTBOOK OF POLLEN ANALYSIS O, Equatorial limb semiangular. Scabrate/microverrucate. Cornus. Cf. Table 7.2 P₂ Grain more than 50 μm. Tectum perforate. P, Grain ca. 25 μm. No perforations.. H, Intercolpium convex. Q: Pore edges distinctly protruding. C. sanguinea C. suecica t. R₂ Endopore equatorially elongated. Grain less than 25μm S, Microechinate, vermiculate . . . S₂ Psilate. Filipendula T₂ Tectum with minute perforations. Endexineheavy. . . T₁ Tectum not perforate. Incl. Castanopsis S, Scabrate or indistinctly suprareticulate. U₂ Operculate.. . Glaux Castanea t. .Sanguisorba minor U, No operculum. Incl. T. spadiceum, Medicago sativa, Astragalus arenarius, A. norvegicus.. R, Endopore circular. Furrow slit-shaped. V₂ With vestibulum. Trifolium montanum t. W₂ Furrow very short, ca. twice the diameter of the pore. W, Furrow longer, distinct Ludwigia Hippophaë V, No vestibulum. Microechinate, columellae in vermiculoid pattern Filipendula Q, Edges ofpore not protruding, endopore meridionallyelongated, isodiametricor indistinct X, Grain perforate. Furrow slit-shaped, endopore small, completely covered. Rumex t.. Y, Grain smaller than 25(-28)μm. Y₂ Grain 25-32μm. Exine thicker Y, Grain larger than 35μm. X, Not so. .Oxyria t. R. longifolius t. R. aquaticus t. Z₂ Grain 25-32μm. Scabrate Z, Grain less than 20μm. Psilate. Fagus Crassula aquatica .WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Table F11.2. Tricolporate. Echinate This table mainly comprises Compositae Asteroideae. Their exine is in typical cases multi-layered and consists of, in centrifugal direction: (1) foot layer; (2) inner columella layer, usually with scattered, coarse, often branched columellae; (3) paratectum formed by anastosmoses between the heads of the inner columellae; (4) outer columellae layer; columellae thinner and denser than in the inner layer; (5) (outer) tectum, which is very thin and densely perforated. It is a matter ofconvenience ifone wants to consider the three outer layers (paratectum, outer columellae and tectum (s.s) as a tectum s.l. A₂ Columellae straight, not branched. Spines with cylindrical base B₂ Diameter of spines and columellae equal. Spinesfew, scattered. .Lonicera B₁ Spines much coarser than columellae, blunt, frequently flaccid (bent over at base) Rubus chamaemorus A Columellae branched, spines conical from base. Asteroideae. C2 Columellae indistinct in optical section. Incl. Antennaria, Aster, Bellis, Bidens, Calendula, Erigeron, Filago, Galinsoga, Gnaphalium, Inula, Petasites, Senecio, Tussilago . Solidago t. C₁ Columellae prominent in optical section. D₂ Inner columella layer equal to or thicker than the outer.. E3 Spines vestigial. F2 Grains large, prolate with longitudinal thickenings of intercolpia (intersemiangulate). . . Echinops F, Grains small, sphaerical-oblate D₁ Inner columellae layer thinner than outer G₂ Spines vestigial. G₁ Spines distinct. .Artemisia t. E₂ Spines blunt, length equal to or smaller than basal diameter. Incl. ^^ Arctium, Carlina, Carthamus, Onopordon . . . . Saussurea t. E₁ Spines long, sharp. Intercolpium in optical section distinctlycrescentic. Incl. Anthemis, Chrysanthemum, Matricaria, Serratula. ^^ Achillea t. .Centaurea scabiosa t. 267268 TEXTBOOK OF POLLEN ANALYSIS (H₂ Grains ca. 30μm or smaller. Sphaerical. Colpi short. Cf. Table F7.3.) H, Grains larger. Colpi long. I, Oblate. Incl. Carduus I Prolate. Incl. C. alba, diffusa, jacea,phrygia. Cirsium t. Centaurea nigra t. Table F11.3. Tricolporate. Striate-rugulate As sculpturing elements, the striae are often difficult to observe and need a very careful focusing, especially in discordant grains. In the marginal figures for entries between I, and M, the outer furrow is indicated in black. A₂ Operculate. See Specialkey A₁ No operculum. Rosaceae B₂ Furrow transversal. Costae transversales present. B, Furrow not distinctly transversal. No costae transversales. Rhus (C₂ Finely verrucate. Furrow very short, ca. twice the diameter ofthe pore Ludwigia C, Striate-rugulate. Furrow much longer than the diameter of the pore. D₂ Grain 25μm or larger. E₂ Pore indistinct. F₂ Edge offurrow undulating. See Special key. . .Rosaceae F, Edge offurrow straight. Striae very distinct. Columellae fine. Menyanthaceae G₂ Costae colpi distinct.. .Menyanthes G, Costaecolpi absent or very thin. Columellae almost imperceptible ... . Fauria E, Pore distinct H, Polar area pointed. Pore covered. Striae fine Helianthemum H, Polar area rounded. Pore not or only partly covered. Gentianaceae (1) I2 All or almost allstriae meridionalWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA J₂ Grain oblate or globular. P/E equal to or less than 1 Lomatogonium J, Grain prolate, P/E more than 1. . Gentiana Centaurium K₂ Grain ca. 30μm. K, Grain ca. 25 μm. I, Some striae not meridional. L₂ Intercolpium median with predominantly meridional striae Centaurium L₁ Intercolpium median rugulate. M₂ Grain ca. 25μm. Intercolpium edges meridionallystriated D, Grain smaller than 25 μm. Striae short. Blackstonia M₁ Grain equal to or smaller than 25 μm. Intercolpium edges with groups of non-meridional striae N₂ Furrow with coarse spines.. Cicendia N, Furrow membrane without ektexine elements. Aesculus O2 Sculpturing of intercolpium indistinct. O, Sculpturing of intercolpium uniform, distinct. P₂ Columellae distinctly visible. . . P, Columellae indistinct-imperceptible Cicendia Sempervivum Table F11.4. Tricolporate. Suprareticulate-foveolate .Sedum A₂ Heteropolar. Pores near the broad end. A₁ Isopolar. Echium B₂ Grain peroblate. Foveolate. Furrows very short. Costae colpi heavy. Exine more than 3 μm thick . . . .Tilia B₁ Grain not peroblate. Furrow not very short. C₂ Grain prolate. Exine more than 2 μm thick. Columellae very coarse. D2 Grain oval. Columellae uniform.. + E2 Columellae simple. Furrows with broad costae. Margo heavy. Euphorbia . 269270 TEXTBOOK OF POLLEN ANALYSIS E, Columellae branched. Margo indistinct. Grain dimorphic. .Fagopyrum D₁ Grain compressed oval. Columellae coarser and more scattered atpoles... Polygonum bistorta t. C, Grains variable. Ektexine less than 2μm thick. Columellae fineor indistinct. F₂ Equatorial limb subangular. Grain oblate. Polar area very small.Costae transversales and pores distinct . . . ... Rhamnus catharticus F, Equatorial limb circular or semiangular. Grain subsphaerical or prolate. Polar area medium. Costae transversales present but not always very strong. Papilionaceae pp. (cf. Fægri, 1956). G₂ Reticulum indistinct. H₂ Grain prolate. Pore distinct, covered bya thin, structureless exine. Incl. Vicia orobus, V. sepium, V. tenuifolium, Lathyrus montanus. H, Grain subsphaerical. Pore covered, more or lessdistinct. I, Grain more than 35μm. Pore indistinct. Exine thin. Vicia cracca t. J₂ Furrow with costae and equatorial bridge. . .Medicago sativa J, Not so..... Medicago falcata I, Grain more than 30μm. Exine thin. Incl. Astragalus arenarius, A. norvegicus. Astragalus spp. I, Grain less than 35μm. Exine thick. K₂ Grain 30-35μm. Columellae distinct. . Trifolium montanum K, Grain less than 25 μm. Columellae indistinct. G₂ Reticulum distinct, some lumina blocked. Trifolium spadiceum L₂ Polar area large. L, Polar area medium. Incl. Oxytropis. G, Reticulum distinct. No lumina blocked. Coronilla emerus Astragalus t. M₂ More than 13-15 equatorial brochi per intercolpium N₂ Lumina with free columellae. O₂ Muri broad. Pore diameter less than ofpolar axis length Astragalus frigidus O, Muri narrow. Pore diameter larger than ofpolar axis length Astragalus penduliflorusWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA N₁ No free columellae in lumina. P₂ Grain more than 20μm. Ononis t. P, Grain smaller than 20 μm. M, Less than 13-15 equatorial brochi per intercolpium Q2 Meridional limb compressed oval. Furrow with heavy costae. Pore distinct, covered by a thin, almost structureless ektexine. R₂ Grain subsphaeroidal. Astragalus alpinus + S₂ Lumina with perforations. Breadth of muri less than diameter of lumina... ..Lathyrus sativus S₁ No perforations in lumina. Muri very broad... Lathyrus palustris R, Grain prolate. T₂ Grain more than 50 μm. U₂ With distinct perforations in lumina U, No perforations in lumina T, Grain smaller than 50μm. Pisum V₂ Lumina with distinct perforations V₁ No perforations in lumina. Viciafaba Lathyrus maritimus Q Meridional limb circular or more or less rhomboidal. Costae colpi variable. Pore covered by ektexine with distinct structure. Trifolium t. W2 Grain more than 40 μm. Incl. Trifolium incarnatum, T. striatum. F11.5. Tricolporate. Per-reticulate-frustillate Vicia t. T. medium t. W, Grain smaller than 40μm. Incl. Medicago lupulina...Trifolium spp. Table A, Reticulum indistinct or frustillate-perforate. B₂ Columellae united only by their topmost parts. Furrow with equatorial bridge. Cf. Hottonia, Table F7.6. Mercurialis. C₂ Exine more than 2 μm thick. Columellae grouped/irregularly distributed. Furrow membrane not with a row of granules . . .M. perennis C, Exine less than 1.5 μm thick. Columellae evenly distributed. Operculum formed by a (single) row of granules. M. annua 271272 TEXTBOOK OF POLLEN ANALYSIS B, Irregularly reticulate-frustillate-perforate, lumina larger in the polar area. Furrow narrow, slightly wider at both ends. Pore small, covered. . . .Vitis A₂ Reticulate-striate. Columellae coarse, isolated at bottom, forming reticulum at middle level and striations at top. Gentiana nivalis A, Eu-reticulate. D₂ Brochi more than 1 μm. E₂ Ektexine thick, usually more than 2 μm. Columellae coarse, distinct. F2 Muri distinctly duplicolumellate G₂ Reticulum irregular; brochi smaller towards colpus. Muri beaded, breadth equal to or smaller than diameter of lumina. With transverse furrow... Hedera G, Size of brochi uniform. Pore meridionally elongated, 6 μm F, Muri usually simplicolumellate... Euonymus europaeus H, Lumina with distinct free columellae, those in muri crowded. Transverse furrow short. I Reticulum very coarse except in the polar area. Equatorial limb subtriangular.. ... Sambucus ebulus I, Reticulum in polar area not different. Equatorial limb tricrescentic. ... Viburnum H, Nofreecolumellae in lumina. Those in muri clearlyseparated. Pore round. Gentianella J₂ Grain more than 40 μm. J, Grain less than 40 μm. Incl. G. tenella. G. campestris .G. amarella E, Exine thin, usually less than 2 μm. Columellae fine or indistinct. K, Equatorial limb subangular... L₂ Grain more than 20μm. Breadth of muri less than diameter of lumina. M, Polar area medium. Size of brochi uniform. With transverse furrow. ..Trientalis M, Polar area very small. Size of brochi decreases towards poles. Pore distinct.. Parnassia L, Grain less than 20 μm. Breadth of muri subequal to diameter of lumina. Exine tricrescentic.. Chaenorrhinum K, Equatorial limb circularWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA N₂ Grain more than 20 μm. Transverse furrow/pore distinct. O₂ Transversefurrow long and bent, almost equatorial. + O, Not so. Lysimachia nemorosa P₂ Distinctly duplicolumellate. Lysimachia nummularia, L. vulgaris, Anagallis.. Lysimachia t. P, Simplicolumellate or columellae indistinct Q2 Muri broad. With transverse furrow. R2 Columellae indiscernible. Margo heavy R, Columellae distinct. Margo thin ....Anagallis Q₁ Muri narrow. No transverse furrow. Incl. Verbascum, Misopates Sambucus niger, S. racemosum D, Micro-reticulate; brochi less than 1 μm. S₂ Furrow slit-shaped. No margo. Pore covered... S₁ Not so. Lysimachia thyrsiflora Scrophularia t. N, Grain smaller than 20 μm. Transverse furrow indistinct. Incl. Sambucust. Rumex sect. Acetosa T₂ Endexine as thick as ektexine. Transverse furrow distinct, narrow Glaux T, Endexine thin. No transverse furrow. Hypericum Table F12. Stephanocolporate All grains are psilate-scabrate except where otherwise indicated. The transverse furrow in Boraginaceae is blunt-ended, pore-like. The number of furrows varies individually; numbers indicated represent averages. A₂ More than 4 furrows. Cf. also Table F19. B₂ Grain larger than 20 μm. C₂ Transverse furrows present. D₂ (Endo-)colpus aequatorialis present. No costae aequatoriales E2 More than 10 furrows. Grain barrel-like (depresed oval) with an equatorial ridge. 273TEXTBOOK OF POLLEN ANALYSIS F, Polar area with several isodiametric lacunae .. . Polygala F, Polar area coarsely vermiculate, no round lacunae Utricularia E, 9-10furrows. Grain spherical. No equatorial ridge. ...Borago D, Mostly 8 meridional furrows. Grain compressed oval. Transversefurrows distinctly separate, pore-like... .Symphytum C₁ Transverse furrows absent. G₂ 5 furrows. Grain more than 40μm, depressed oval to polyedric. Polar area with an intectate field of coarse columellae. Cf. M₂... G₁ 6-7 furrows. Viola arvensis H, Reticulate. Grain spherical.. Pinguicula H, Psilate. Grain prolate. Operculum very broad Sanguisorba officinalis B, Grain smaller than 20 μm, compressed oval I, Meridional furrows very short, hardly discernible. (Protruding poroid area with free granules operculum) . Buglossoides arvensis I, Meridional furrows distinct. J, Costae aequatoriales present. Sculpturing ofequatorial belt almostinvisible in LM... . . .Pentaglottis J, Costae transversales almost contiguous. Grain sub-heterocolpate (three furrows withcross-shapedporoid area). Cynoglossum A, Four furrows. K, Grain larger than 40μm. L₂ Transverse furrow distinct. Grain oval. L₁ No transverse furrow. intectatefield ofcoarse columellae. M, Grain oval. Exine structure uniform. Anchusa arvensis M, Grain depressed oval (barrel-shaped) to polyedric. Polar area with an Viola tricolor Viola riviniana t. 0 274WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA K, Grain smaller than 40 μm. N, Grain compressed oval. Equatorial exine reticulate. Transversefurrow present O, Exine thinner in polar area. Equatorial reticulum coarse O, Exine thickness uniform. P₂ Grain more than 20μm. Nonea Q Meridional furrows with margo ofcoarse columellae Pulmonaria Q Meridional furrows not with coarse columellae.. Anchusa officinalis P, Grain smaller than 20 μm. Sculpturing of equatorial belt nearlyinvisible in LM. Costae equatoriales present. .Pentaglottis N, Grain constricted oval. No transverse furrows. Pores (but not constriction) nearer one pole. Incl. Buglossoides purpureocoeruleum.. Table F13. Pericolporate Lithospermum officinalis Within the area we know of no exclusively pericolporate pollen types. Tri- or stephanocolporate grains sometimes appear with more apertures than normal, and are then usually imperfectly isometric. The most important cases are those set out below. A, Echinate, tectate, exine thick. Cf. Table 11.2. A Psilate or reticulate. ....Compositae asteroideae 275 B₂ Minutely microechinate. Perforations visible in LM. Transverse furrow sometimes present. Pore often missing, furrow membrane beingruptured Polygonum oxyspermum t. B₁ Psilate with perforations and/or reticulate. Furrow slit-shaped. Pore covered. Cf. Table F11.1. . . Oxyria, Rumex Table F14. Diporate Colchicum is regularly, Betula, Myriophyllum, etc. are exceptionally diporate. Cf.also Table F6.TEXTBOOK OF POLLEN ANALYSIS Table F15. Triporate о A₂ With large, cylindrical vestibulum, more than 10μm deep. Onagraceae B₂ Grain 50μm or larger. Incl. Epilobium B, Grain smaller than 50μm.. A, Vestibulum smaller, conical, orabsent. Chamaenerium t. Circaea C₂ Distinctly echinate. D₂ Grain more than 60 μm. Exine thick, more than 4 μm. Dipsacaceae. E₂ Spines short, broad-based, scattered. Pore with well developed anulus Dipsacus E, Spines slender, dimorphic, crowded. Anulus indistinct.. Knautia D, Grain smaller. Spines uniform, scattered: Campanulaceae. F₂ Grain larger than 25μm. Incl. Phyteuma F, Grain smaller than 25μm. . . C, Psilate-scabrate. Campanula t. Jasione G₂ Equatorial limb almost circular, without protruding pore edges. H, Grain more than 20 μm. Micro-sculpturing faintly rugulate with minute spines. Columellae very distinct, scattered.. .. Celtis H₂ Grain more than 20μm. Micro-sculpturingapparentlydotted H, Grain smaller than 20 μm. Psilate. Columellaedelicate. Cannabis I2 After a slight rise the tectum bends down, forming a sunkenpore I, Tectum rises slightly at pore, not sunken. Humulus t. J₂ With minute projections. Exine very thin. Urtica. K, Spinules scattered. K, Spinules closer together, more regularlydistributed J, Projections slightly coarser. Exine slightly thicker U.dioica U. urens Parietaria 276WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA G, Equatorial limb semiangular or with protruding pore edges. L₂ Micro-sculpturing and structure densely and regularly dotted. Juglandaceae, Myricaceae... LcaSum M₂ Pores not exactly in the equatorial plane. Exine thick. Grain 30-50μm M, Pores in the equatorial plane. Carya о N₂ Grain more than 20 μm. Pore broadly conical, interior walls of pore chamber with irregular elements. N, Grain smaller than 20 μm. O₂ With 2 long pseudocolpi Myrica O, No pseudocolpi. . . Platycarya Engelhardtia L₁ Micro-sculpturing and structure more or less rugulate, with scattered minute spinules on top of low vallae (ph!). Betulaceae. . . P2 Equatorial limb circular with protruding pores. Exdexine and tectum diverge in the pores, forming a vestibulum. L ca 5um Q2 Vestibulum distinct. Tectum sharply thickened at the pore. Cf. Table F11.1: V₂ Ludwigia .. . Betula Q₁ Vestibulum not distinct. Tectum not appreciably thickened at thepore. Incl. Carpinus. . . Ostrya t. P, Equatorial limb semiangular, pore not protruding. Endexine and tectum do not diverge in the pore. Depth ofpore not much greater than thickness of the regular exine. Corylus Table F16. Stephanoporate A, Echinate. Spines distinct, regularly distributed. Campanulaceae. B2 Grain larger than 25 μm. Incl. Phyteuma B, Grain smaller than 25 μm... Campanula t. Jasione A₂ Coarsely and softly rugulate or suprareticulate. Peroblate. A, Psilate, scabrate or very delicately rugulate. Ulmus C₂ Grain globular. Equatorial limb circular. Pores not distinctly protruding D₂ Rugulate, spinulose.. Celtis . 277278 TEXTBOOK OF POLLEN ANALYSIS D, Psilate. Columellae delicate. E₂ Grain more than20μm. Cannabis E, Grain 20μm or smaller. F₂ Pore sunken. Cf. Table F15: I2. F, Pore not sunken. Humulus t. G₂ Exine very thin, structure very delicate. Cf. Table F15. . Urtica G, Exine thicker, structure coarser.. Parietaria C, Grain oblate. Equatorial limb more or less angular and/or pore edges protruding. H₂ Neighbouring pores (anuli) connected with thickened bands (arci). Pore with thick anulus . Alnus I, Pores meridionally elongated with endexinous anuli. Myriophyllum J₂ Equatorial limb irregular (basically ellipsoid). Grain triaxial. Pores grouped, strongly protruding.. ...M. alterniflorum J, Equatorial limb regular. Pores equidistant. K₂ Anulus distinct, protruding. M. spicatum t. >> K, Anulus externallyflat, not protruding M. verticillatum I, Exine thickness uniform. Pores circular, without endexinous anuli. L2 Equatorial limb semiangular. Micro-sculpturing dense and regular. Platycarya L, Equatorial limb more or less circular. Grain more than 40μm. Microsculpturing faintly rugulate with minute spinules on vallae. Carpinus Table F17. Periporate: Main key to subsections Verrucate-echinate Vermiculate-rugulate or reticulate Table F17.1 Psilate-scabrate.. Table F17.2 Table F17.3 .WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Table F17.1. Periporate. Verrucate-echinate A Verrucate. Special key A, Echinate. B₂ Ca. 100 pores. Grain large, spines strong Plantaginaceae B₁ 8-20 pores. C2 Pores without anuli. Malvaceae D₂ Pores sharply delimited, elongated, pore membrane without spines Koenigia D, Pores less distinct, isodiametric; pore membrane with spines. Alismataceae. E2 Spines with broad, compressed base. . . . . . Sagittaria E, Spines with cylindrical base, on low verrucae .Luronium t. C, With anulus. Special key.. Caryophyllaceae pp. Table 17.2. Periporate. Vermiculate-rugulate or reticulate A₂ Vermiculate-rugulate. B₂ Coarse columellae. More than 50 pores. B₁ Columellae fine. Less than 50 pores Polemonium A Reticulate. C₂ Pores with anuli. D2 Columellae evenly distributed. Breadth of muri subequal to diameter of lumina D₁ Not so. Special key C, Anuli absent or indistinct. Buxus E2 Reticulum regular, very coarse. Bottom of lumina with a pore and/or covered with granules. Polygonum foliosum, P. hydropiper, P. lapathifolium, P. persicaria, P. tomentosum Polygonum sect. Persicaria E₁ Not so. Liquidambar Caryophyllaceae pp. 279280 TEXTBOOK OF POLLEN ANALYSIS F2 Pore indistinct, included in a brochus. Brochi with pore slightlylargerthan those without. Columellae elongate, club-shaped, fused at top, forming reticulum Daphne F, Pore distinct, larger than brochi. G₂ Edge of pore distinct.. Liquidambar G₁ Edge of pore not distinct. Buxus Table F17.3. Periporate. Psilate-scabrate TECTUM SOLIDUM TECTUM PERFORATUM A, Grain irregular, usually pear-shaped. Pores indistinct. Special key. . Cyperaceae A, Grain regularly ellipsoidic. B, Microechinate, dotted. C₂ Columellae fine, evenly distributed. Pores aggregated towards one pole Juglans C, Columellae coarse and/or irregularly distributed. Pores evenly distributed. D₂ Anulus distinct. Special key... Caryophyllaceae pp. D, Anulus absent or indistinct E₂ Surface undulating. Special key. B, Not Plantaginaceae E, Surface even. F₂ Grain more than 25μm. Indistinctly intrareticulate. G₂ Grain sub-polyhedric. Exine between pores distinctly crescentic. Pores round. ....Alisma graminea G, Grain (sub-)globular. Exine not distinctly crescentic. Pores irregular, indistinct... F, Grain 10-25μm. No intrareticulum. microechinate, dotted. .Papaver argemone Thalictrum H₂ Areas without tectum, surrounding and connecting pores H, Tectum not reduced. Ribes I, Grain large (70-80 μm). Exine thick. I, Grain smaller. CalystegiaWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA J₂ Anulus present. K2 Anulus distinct, but often narrow and without structure. L2 Tectum without perforations. Number of pores usually higher than 50. Incl. Amaranthaceae Chenopodiaceae L, Tectum perforate (indistinct in Sagina ).Number of pores lower than 50. M, 6-12 large pores. Tectum very thick. Anulus prominent. Columellaevery fine and short. M, Not so. Special key .... Fumaria Caryophyllaceae pp. K, Anulus diffuse. Columellae widely dispersed in interporia, dense on anuli. Grain usually polyhedric. Intrareticulate. Alismataceae. N₂ Grain less than 25μm. N, Grain more than 25μm J₁ No anulus. Baldellia Alisma plantago-aquatica O₂ Grain 10-25μm. 4-12 pores. P₂ Grain rounded. Distinct minute spines. P, Grain sub-polyhedric. Indistinctly dotted. O, Grain ca. 10 μm. No spines. 4 pores Table F18. Syncolpate Thalictrum Polycnemum/Paronychia t. .Herniaria Colpi sometimes fuse at one pole also in grains not considered, here, syncolpate. A₂ Heteropolar. Colpoid furrowsjoining at one pole. Coarsely reticulate Thesium A₁ Isopolar. оо B3 Furrows meridional. C₂ Twofurrows,fusedto a ring. Grain usually split, edges ofcolpus ragged. Psilate perforate-perfossulate. Cf. Juniperus, Table F2. . Pedicularis C₁ More than two furrows. D₂ Furrows bifurcate, fused with neighbouring furrows, delimiting a polar field.. E2 Grain larger than 30 μm. Coarsely striated.Polarfield large Nymphoides E₁ Grain 10-25μm, dimorphic. Minutely per-reticulate. Primula. 281TEXTBOOK OF POLLEN ANALYSIS F₂ 3-4 furrows. Size 10-15μm. P. farinosa F, 4-6 furrows. Size 20-25μm. D, Furrows 3, notbifurcate G₂ Grain microverrucate P. scandinavica t. Loranthus G, Grain psilate. Short transverse furrow present. Incl. Eucalyptus. B₂ Furrows spirally oriented. . . Myrtaceae H, Grain with scattered spinules, not perforate.. H, Grain reticulate, heterobrochate. Exine usually splits Eriocaulon Berberis B, Peri-syncolpate. Exine divided into angular plates, usuallyfalling apart I, Grain reticulate, heterobrochate I, Grain pitted (perforated). Berberis t. Mahonia t. Table F19. Heterocolpate There are some grains in which there is a certain difference between furrows. However, we have here restricted ourselves to dealing with grains with colpoids or regular furrows without pores alternating with such that possess pores. A Tricolporate with meridional folds at both sides ofthe regular furrow. Thefolds may fuse at the pore(s). Cf. also Anthyllis, Table F11.11 . . . . . Verbena A Threefurrows with pores alternate with threesimilar without B₂ Furrows approximately equally long. Grains dumbbell-shaped (constricted oval). Polar area index large, above 0.5. Boraginaceae. C₂ Grains smaller than 10 μm. Incl. Lappula.. C, Grain more than 10μm.. . Myosotis t. B, Aporate furrows generally shorter than the porate ones. Polar area small. Grain not constricted. Lythraceae. Mertensia D₂ Aporatefurrows distinctly broader than the porate ones. ... Peplis D, Aporate furrows not broader than the porate ones. Grains dimorphic Lythrum 0 282WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Table F20. Fenestrate (A, Non-meridional tectum-less areas surrounding and connecting pores. Ribes A₂ Grains psilate. B₂ Polar area with small lacunae. More than 8 furrows B, Polar area without lacunae. Three meridional lacunae alternate with porate furrows... Grains echinate, lophate. .. . . Polygala .. Peplis O Compositae Cichorioideae Caryophyllaceae (periporate) cf. Chanda, 1962; Fredskild, 1967 The section Sperguleae has colpate grains, cf. Table F7.1. A₂ Grain ca. 10 μm. 1-8 pores. Sect. Paronychieae: Herniaria, Illecebrum, Corrigiola Herniaria t. A₁ Grain larger than 10 μm. B3 Tectum with scattered distinct perforations similar in numberto the columellae and spines, or per-reticulate. Sections Lychnidae, Diantheae; also Honckenya C₂ Anulus broad. Usually 12 pores. Most species incl. G.fastigiata, G. repens... .. Gypsophila pp. C₁ Anulus less broad. D₂ Less than 20 pores. Incl. Dianthus, Tunica, Saponaria, Silene pp. Dianthus t. D, More than 20 pores. Incl. Lychnis, Melandrium, Agrostemma, Viscaria, Silene pp., Honckenya. Lychnis t. B₂ Tectum with indistinct perforations, distinctly scabrate. Pores small, more than 24. Incl. Chenopodiaceae. . . .Sagina B, Tectum with minute perforations that are much more numerous than columellae and spines. Section Sclerantheae, Alsineae, not Honckenya E2 Pores (+anuli) in depressions, surrounded by a zone without big columellae; the rest of the grain forming a hexagonal pattern ofridges. Pores 12 or about 20. F2 Ridges scabrate or with indistinct sculpturing ...Scleranthus F, Ridges echinate. . . Stellaria holostea E, Not so. Pores 6-ca.40. Incl. Cerastium, Stellaria, Malachium, Arenaria Cerastium t. pp., 283 83 ATEXTBOOK OF POLLEN ANALYSIS Cyperaceae Grains with perforate tectum with lacunae, i.e. areas where the tectum is broken up into small frustillae, usually forming an areolar sculpturing. The form and arrangement of lacunae is of great diagnostic value. They are most easily seen in strongly stained preparations. Columellae are sometimes clearly visible, each frustillum borne by several columellae. One or two of the lateral lacunae may be smaller than the others; the indices given below do not applyto these. A, Lateral lagunae oblong, length twice as long as the breadth or more. Grainovoid or pear-shaped. B Length of lateral lacunae more than half that of the grain. . . C Grain more than 40 μm. Incl. Heleocharis spp., Rhynchosporafusca Schoenus t. C, Grain less than 40 μm. Incl. Heleocharis palustris. Schoenoplectus t. B, Length oflateral lacunae less than half ofthat of the grain. Grain more than 40 μm. Scirpus maritimus A Lateral lacunae more or less circular or slightly elongated. Grain ovoid or pear-shaped. D 2-3 small lacunae, length less than 20% that of the grain. Grain more than 40μm, the narrow end usually projecting like a beak ora finger Cladium mariscus D, 4-6 lateral lacunae, their length normallymore than 20% ofthat ofthe grain. Grain smaller than 40μm, exceptionally (Carex hirta) 40-50 μm. The narrow end rounded: Carex type. E2 Length of lateral lacunae 20-35% ofthat ofthe grain. Incl. Carex, Scirpus silvaticus Dulichium t. E, Length of lateral lacunae 30-50% of that of the grain. Incl. Trichophorum... . Eriophorum t. A, Lacunae irregular, rather large. Grain almost isodiametric, less than 30μm. Structure rather coarse, columellae distinct ...Rhynchospora alba t. Gramineae Owing to the great importance of grasses, both in natural plant communities and in cultivated areas, and also the importance of certain taxa as cultivation indicators, it would be highly desirable to be able to identify grasses to species. However, the paucity of distinguishing characters sets very narrow limits. The Gramineae pollen type is easily recognized, but also very monotonous. The characters that have been most frequently used are quantitative: diameter of grain, ofpore and ofanulus. Like all such characters their value is limited, especially as size seems to change with time. By statistical methods it is possible to differentiate between the pollen of various taxa 284WHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Fig. 12.5. Single- and double-grain structure in grass pollen. if there is a sufficient number and no admixtures, but since the variation curves overlap, identification of individual grains remains impossible or doubtful. When using data from the literature one must take into consideration thatsome refer to glycerol (jelly) preparations (e.g. Beug, 1961), others to silicon preparations (e.g. Andersen, 1978). For the same species, conversion factors vary between 1.1 and 1.3 for grain size and between 1.1 and 1.5 for pore data. Inasmuch as theyhavebeen used in the key below, Andersen's data have been modified by a factor of1.2. Grass pollen sometimes possess a soft, verrucate sculpturing, which is, however, difficult to observe in LM. It is not known if this is an artifact of preparation or a specific character, and it has so far not been used for diagnostic purposes. In contrast, the structure shows differential patterns, which can be seen with adequate optical equipment, and which in northwest European grasses varybetween two main types. In the one, single-grain structure, columellae are individually free, moreor less crowded and more or less aggregated. In the double-grain structuresome or all columellae are united into small frustillae, cf. Fig. 12.5. As has been pointed out by Beug (1961) one can also distinguish between even distribution and aggregation of free columellae. In addition, columellae may form more or less distinct reticulae. In spite of a fairly extensive literature on the topic, a modern reconsideration of grass pollen morphology is overdue. This key chiefly depends on the use of quantitative characters, theweakness of which has been mentioned. With few exceptions identification is subject to statistical uncertainties and even the comprehensive groups of the key are not too welldefined. Measurements all refer to glycerol preparations. A, Grain more than 60 μm A₂ Grain between 40 and 60 μm: Cereal type. .Zea mais B₂ P/E ratio higher than 1.25. Pollen distinctly scabrate. Pore lateral B, P/E ratio less than 1.25. Pore (sub-)apical. Secale cereale C₂ Anulus diameter larger than 12μm. D2 Exine with single-grain structure. D, Exine with double-grain structure C₁ Anulus diameter between 10 and 12μm: Hordeum type. Triticum t. .Avena type. E2 Grain more than 44μm. Outer limit ofanulus indistinct E₁ Grain less than 47μm. Elymus s.l. The terms punctae, maculae and areolae, which have been used in previous editions, are redundant andshould be dropped nowthatimprovementofoptical equipmentpermitsunequivocal recognition of the true nature of these structures. They are easily perceived, especially after staining and/or in swollen grains. 285286 TEXTBOOK OF POLLEN ANALYSIS F2 Outer limit of anulus sharp. Incl. Hordeum, Agropyrumjunceum F, Outer limit of anulus not sharp.. Triticum t. Agropyrum t. A Grain smaller than 40μm. Anulus diameter less than 10μm: wildgrass t. G₂ Grain smaller than 26 μm. Columellae indistinct. . . . . .Phragmites. G, Grain between 26 and 40 μm. H₂ Double-grain structure. Columellae distinct. Incl. Nardus, Cynosurus Dactylis t. H, Single-grain structure, some aggregation opposite the pore. Incl. most wild-grasses. Festuca t. Plantaginaceae Cf. Bassett and Crompton, 1967; S. T. Andersen, 1970 A₂ Pore with distinct anulus. B₂ Pore operculate. C₂ More than 8 pores; grain distinctly micro-echinate. . P. lanceolata C₁ Less than 8 pores; not distinctly micro-echinate, though minute punctae may be seen in Ph .. P. coronopus B, Pore rarely operculate, but with isolated granules. 5-9 pores. Distinctly micro-echinate.. ...P. maritima, P. alpina A, Pores without distinct anulus, with granules, no operculum D2 Grain normallymore than 30μm. Pores numerous, sharply delimited. Littorella uniflora D, Grain less than 30μm. E2 Pore sharply delimited, 5-9. Distinctly micro-echinate. .P. maritima E₁ Pore not sharply delimited. F2 Punctae indistinct or invisible. . F, Punctae distinct (Ph). G₂ Verrucae rather indistinct or very small. Pores numerous G₁ Verrucae distinct. P. major H2 Verrucae very coarse. H, Verrucae less coarse. P. tenuiflora P. media P. montanaWHICH PLANT? IDENTIFICATION KEYS FOR THE NORTHWEST EUROPEAN POLLEN FLORA Rosaceae A2 With tectate operculum. Cf. Eide (1981). B₂ Psilate-scabrate-echinate, oblate-globular. Sanguisorba. C₂ Operculum narrow, furrow veryshort. D2 Vallae coarse. Perforations I not visible. S. minor C, Operculum as broad as the intercolpium, furrow long. S. officinalis B, Striate. E₂ Vallae rarely parallel. Operculum extremely narrow, pore always distinct.. ...Sibbaldia procumbens E, Vallae often parallel. Operculum narrow to broad, pore not always distinct. F2 Vallae broad, diffuse. G₂ Prolate. Colpi constricted, ends rounded Comarum palustre G₁ Not prolate. Colpi not constricted, ends acute. H₂ Polar area flattened. H, Polar area not flattened. F₁ Vallae narrow, distinct. I₂ Colpus ends rounded. I₁ Colpus ends acute D, Vallae fine. Tectum perforate. Fragaria vesca .Potentilla spp. Fragaria viridis .Potentilla spp. J₂ Vallae transversal, extremelyfine. Operculum extremely narrow. Agrimonia J, Vallae submeridional to subtransversal. Operculum short... Rosa A, No tectate operculum, but colpus membrane occasionally with loosecolumellae. K4 Clavate-baculate-echinate .. K, Microechinate-echinate. No perforations.. K2 Rugulate-microstriate/psilate K, Striate. ... Rubus chamaemorus .Filipendula L, Rugulate-microstriate. No costae colpi or granules on furrow membrane L₂ Rugulate to psilate, costae colpi and granules usuallypresent... Mespilus germanica L, Psilate. Polar projection usually subtriangular... Cotoneaster Alchemilla 287TEXTBOOK OF POLLEN ANALYSIS M2 Vallae coarse. Colpus with distinct bridge.. Geum M, Vallae fine. N, Vallae paired.Striation weak. N, Vallae simple. Crataegus O Vallae indistinct. Perforations large. Rubus O, Vallae distinct. P2 Vallae high, frequentlyshort. P, Vallae low and narrow. Q: Vallae straight, moderately branched. Rosa R₂ Perforations distinct. Vallae without dense structure Sorbus R, Perforations maybe unobservable. Vallae withdensestructure Q, Vallae curved, branched, anastosmosing. S, Vallae short, strongly curved. . . S, Vallae moderatelycurved. T₂ With costae colpi, size ca.27μm Prunus T, No costae colpi. Size ca. 22 μm. Dryas