.,^ ; ■— ;;§i^:1fiSsggiH??^ ..im«i»-»»t''ffW.'n., -niiMtitieCEklui' POLLEN AND SPORE MORPHOLOGY/ PLANT TAXONOMY a ^ d X Juniperus coninuinis, part of an acetolyzed megaspore membrane at dilTerent adjustments of the microscope from high (a) to low (d). x 1000. POLLEN AND SPORE MORPHOLOGY/ PLANT TAXONOMY GYMNOSPERMAE, PTERIDOPHYTA, BRYOPHYTA (ILLUSTRATIONS) (An Introduction to Palynology. II) BY G. ERDTMAN With frontispiece, 5 plates and 265 illustrations MARINE BIOLOGICAL LABORATORY LIBRARY WOODS HOLE, MASS. W. H. 0. I. ALMQVIST & WIKSELL/ STOCKHOLM THE RONALD PRESS COMPANY/NEW YORK Almqvist & WikselllGebers Forlag AB STOCKHOLM 1957 PRINTED IN SWEDEN BY Almqvist & Wiksells BOKTRYCKERI AKTIEBOLAG UPPSALA 19 5 7 PREFACE The second part of "An Introduction to Palynology" deals, as was orig- inally planned, with pollen and spore morphology in the Gymnospermae, Pteridophyta, and Bryophyta. Although the illustrations and most parts of the text were ready for printing in the autumn of 1956, the completion of the text had to be somewhat postponed on account of my absence abroad for several months. It was accordingly decided to publish the second part in two instalments: thus, the present volume (Vol. II) consists mainly of illustrations, whereas the following volume (Vol. Ill) will provide the related text. Most of the illustrations are palynograms drawn after the author's origi- nals by Anna-Lisa Nilsson. They depict, in a standardized manner, a pollen grain or spore in polar and/or lateral view, together with its sporo- derm stratification and other details. It should be emphasized, however, that the sporoderm stratification details merely hint at the great array of patterns and layers which exist. Pending thorough morphological investiga- tions, the proper interpretation of these layers etc. is still, in many cases, largely conjectural. Besides the palynograms, some photomicrographs and electron micro- graphs of very thin sections through spore walls are included. Stimulated by my eminent friend. Dr. R. W. Kolbe, the microscopist and diatom specialist, I tentatively took up — in the late nineteen-forties— electron microscopy as an aid in sporoderm research. These studies have been continued, with better technique and greater success, by Dr. Barbro Afzelius, to whom I am indebted for the electron micrographs here re- produced (with the exception of those of PI. IV and V, which were put at my disposal by Dr. D. von V^ettstein) and for a chapter (pp. 125-134) on the application of new microscopical techniques in palynological research. Another chapter (pp. 135-147), by J. Radwan Praglowski, deals with the technique of making very thin sections from spore material embedded in plastic. As shown by Fig. 1 (p. 2), this technique can also be applied in the study of very old (Palaeozoic etc.) spores. In conformity with Vol. I, the present volume has been prepared under the auspices of the Swedish Natural Science Research Council. Help and support of various kinds received from other sources will be duly acknowl- edged in Vol. III. Palynological Laboratory, Stockholm -Bromma, July 1957. G.E, CONTENTS INTRODUCTION ^ On the exine morphology of the saccate pollen grains in recent gymnosperms ^ ILLUSTRATIONS ^ Gymnospermae (Abies — Widdringtonia) 5 Pteridophyta (Acrostichum — Xiphopteris) 45 Bryophyta (Acroschisma — Voitia) "" SUPPLEMENT 125 On new methods in physical cell research and their application in studies of pollen grains and spores. By B. M. Afzelius . . 125 On the cutting of ultra-thin sections. By J. Radwan Praglowski 135 INDEX 148 MARINE BIOLOGICAL LABORATORY LIBRARY WOODS HOLE, MASS. W. H. 0. !. J G6 ' 1 Fig. 1. Setosisporites sp. (material supplied by Dr. Gerhard Krenip), section (thickness about 0.5 ^) through part of the sclerine at high (left) and low (right) adjustment of the microscope, x 1000. INTRODUCTION ON THE EXINE MORPHOLOGY OF THE SACCATE POLLEN GRAINS IN RECENT GYMNOSPERMS The saccate pollen grains in recent gymnosperms are heteropolar, bi- lateral or radiosymmetric (sometimes slightly asymmetric). They consist of a body (corpus) and a varying number of airsacks or bladders (sacci). The aperture is distal, and should often perhaps more appropriately be referred to as a tenuitas (i.e., a thin aperturoid area functioning as an aperture and gradually merging into the surrounding exine). It has earlier, as a rule, been described as a sulcus or a sulcoid groove. The surface of the corpus of a pollen grain with n bladders can be divided into the following areas: n saccale areas, forming the floor of the sacci, n mesosaccale areas (mesosaccia), i.e. areas between the sacci and in the same latitude as these, and finally two aposaccale areas (aposaccia), one at the distal pole, and the other, usually much larger than the former, in the proximal face of the grain with the proximal pole in its centre. With respect to the thickness of the exine of the corpus certain pollen types (cf. e.g. Figs. 53 and 57) exhibit two distinct exine areas: a proxi- mal, crassi-exinous (referred to as cap, cap pa), and a distal, tenui-exinous (referred to as cappula). The non-saccale exine of the cappa consists of comparatively thick sexine and thin nexine. The outer, ectosexinous part of the sexine is usually thin, tegilloid, and as a rule connected to the nexine— except within the sacci— by baculoid, densely spaced endo- sexinous elements. The sacci are separated from the interior, non-exinous parts of the corpus, by saccale nexine. Their outer wall consists of thin ectosexine which is often perforated (shown in electron micrographs— not published — by Erdt- man and Thorsson in 1950). The small holes (micropuncta) are usually difficult to observe through an ordinary light microscope. In the majority of the Tsiiga species the ectosexine of the sacci (as well as that of the corpus, cf. Fig. 73) is studded with spinules or small spines. Attached to the inner surface of the outer wall of the sacci are endo-sexinous elements protruding into the lumen of the bladders (in Pherosphaera fitzgeraldii stray endo- sexinous rods are also found on the saccale nexine). These elements are more widely spaced than those of the body. Branched or unbranched, single or combined in different ways, they tend to produce an array of patterns which are difficult to draw and hard to describe. Microtome sections (cf particularly Afzelius in Grana palynologica, 1:2, 1956) make these subtle details of pollen construction easier to observe and safer to interpret. Near the proximal root of the sacci are often found slight, sexinous ridges or frill-like projections (proximal crests, cristae proximales, also referred to as cristae marginales) varying in appearance in different species. At the distal root of the sacci, where these merge into the distal aposaccium, the characteristic pattern of the bladders comes abruptly to an end. The height of the corpus coincides with the polar axis (i.e. the perpen- dicular line connecting the poles); the breadth is identical with its maximum horizontal extension in grains in equatorial longitudinal view (marginal crests extending beyond the general surface of the corpus not included), and the depth (in bilateral grains) is equal to the transverse ("non-sacci- ferous") diameter of the corpus. It is often preferable and, at the same time, easier to calculate the inner dimensions of the corpus. The height of a saccus is the shortest distance from the highest point of the saccus (or from a line drawn through this point parallel to the saccale nexine) to the underlying nexine of the corpus. Its breadth is equivalent to the "tangential" diameter of the saccus in pollen grains in polar view. In radiosymmetric grains the breadth can also be measured in pollen grains seen in equatorial view; bilateral grains must be in a transverse equatorial position if the breadth shall be measured. In microscope slides this, how- ever, is seldom the case. Its depth— in bilateral grains— is equal to the maximum diameter of the saccus in grains in equatorial longitudinal view. In radiosymmetric grains the depth is calculated is a similar way. Height, breadth, and depth of corpus and sacci are illustrated in Figs. 2, 3, 13, 23, 27, 43, 53, 57, 58, and 62. As shown by Afzelius the inner part of the nexine (the endonexine) in Ce- drus is laminated (Fig. 12, p. 11). In acetolyzed pollen grains of this genus, and of Abies, etc., it can often be seen, even by means of an ordinary microscope, that the nexine consists of two distinct layers, which often split apart as a result of the chemical treatment. So striking is this feature that it seems extraordinary that it has not been mentioned until now. The morphology of bisaccate pollen grains has been dealt with by nu- merous botanists, among whom was Strasburger, who believed that the floor of the sacci was formed by intine. This opinion has often been echoed right up to recent years, although Strasburger himself soon corrected his mistake. In conclusion, it ought to be mentioned that, according to Ciguriaeva, the thin ends (with sexine and nexine slightly separate from each other) of the pollen grains in Ephedra and Welwitschia may be interpreted as the remainder of true sacci. ILLUSTRATIONS GYMNOSPERMAE Frontispiece; PL I (facing p. 12), PL II (facing p. 20); Figs. 2-73. MEGASPORES Cupressaceae: Frontispiece; Figs. 36- Pinaceae: Figs. 44 (p. 2(S), 52 (p. 32), 41 (pp. 23-25). 63 d (p. 40). Podocarpaceae: Fig. 19 (p. 14). POLLEN GRAINS Araucariaceae: Figs. 5 (p. 8), 7 (p. 9). Cephalotaxaceae: PL I (Fig. 2); Fig. 14 (p. 12). Cupressaceae: Figs. 4 (p. t ■■■*■. « f ■ * -i,- . «> «, *»-■. «. -■■.-ss^;-. ;>'•;. ■fSi^ « ^ '■i^-:^ «' 4t * ^>;*S?> i« ^^::V.•.w.. •. ■•,•.■.••■.•■■_ Fig. view view 1: 3-3. 2. A, Abies nephrolepis; a, lateral longitudinal view; b, lateral transverse ; c, polar view (distal face), x 650. B, A. magnified, lateral longitudinal . X 650. C, A. inariesii, saccus pattern (about x 2500). distal pole, 4: proximal pole. Corpus: height 1-4, breadth 5-5, depth Sacci: height 9-8, breadth 10-10, depth 11-11. Total grain: height 4-12 (A: a, b), breadth 13-13, depth 3-5-3 (A: b), 3-2-1-2-3 (A: c). Eleven of the inserted photomicrographs show the pattern of the outer surface of the sacci at dilTerent foci (Ihe uppermost photomicrograph in each saccus shows the pattern at high adjustment of the microscope, the lowermost the same at low adjustment). Two of the photomicrographs between numerals 11 and 8 in A: a and B show^ a part of the saccus in optical cross-section. The remain- ing four photomicrographs exhibit the pattern of the corpus. Those in A: b are phase contrast pictures. (From Erdtman in Svensk bot. Tidskr. 1954.) ACMOPYLE:— Fig. 3. Acmopijle pancheri. For explanation of numerals see Fig. 2. 8 ACTINOSTROBUS:— ^."^^^j Fig. 4. Actinnstrohns nciiminatiis, surface and optical cross-section. xlOOO. AGATHIS:— •.■■■;o',;' " Fig. 5. A, Agatlus microstachya, exine stratification, x 2000. B, A. ovata, exlne stratification (a; x 2000) and LO-patterns (b-d). AMENTOTAXUS: j*^ .'»;• '•#»• Fig. 6. Amentotaxus argotnenia; di, distal pole; pr, proximal pole. From left to right: three still loosely united pollen grains (tenuitas distal; x 250); exine stratification ( x 2000); lateral view, surface and optical cross-section ( x 1000); LO-patterns; pollen grains in polar view ( x 250). 9 ARAUCARIA:— Fig. 7. Araucarid luontaim (exine stratification), a, transition from tenuitas (left) to the thickwalled rest of the grain (right). Layers interpreted in the same way as in b. — b and c, exine stratification outside tenuitas (alternative interpretations); c, shows a thin "nexine" (possibly consisting of two layers) overlain with a thick "sexine" exhibiting three layers: an "endosexinous" faintly-marked layer (consisting of baculoid rods?) merging into a thick, ± granular "ectosexine" ("tegillum"), beset with piloid "suprategillar" processes. According to the interpretation given in b, thin "sexine" ("pila") covers a thick "nexine" (the rest of the exine). — d, LO-patterns ("pila"). X 2000. ARCEUTHOS: see Fig. 42 B, p. 26. ATHROTAXIS:— \'' Fig. 8. Athrotaxis cupressoides. From left to right: exine stratification (x2000); lateral view of opened grain (x 1000); LO-patterns. AUSTROTAXUS:— . . _.. -r^-j- o-»^f jS?>S« v/ Fig. 9. Austrotaxus spicata. Main figure: surface and optical cross-section (X 1000). Details: exine stratification (x 2000) and LO-patterns. 10 BOWENIA: hfi ■ - I J/ 1 3x Fig. 10. Bowenia spectabilis. Details marked 3 x enlarged 3000 times The main figme shows the distal face (sm-face and optical cross-section), x 1000. CALLITRIS:— r-ge 9VI Fig 11. Callitris balansae var. alpina. Main figm'e: surface and opt^^^l/^^^f; section (X 1000). Details (from left to right): lateral view of opened giain (X 250); exine stratification (x 2000); LO-patterns. CEDRUS:— C. atlantica [PI. I (facing p. 12); Fig. 12 a, b], C. deodara (Fig. 13). 11 Fig. 12. Ccdrus (itlnntica. a, section through part of an acetolyzed pollen wall; from top to bottom: cctosexine, endosexinous rods, eetonexine (homo- geneous), endonexine (laminated; the black horizontal line indicates 1 /n; X 22.000); b, endonexine (from another section; magnification greater than in a). KMd B. M. Afzelius. Fig. 13. Cedrus deodara. For explanation of numerals see Fig. 2, p. 7. 2-565617 G. Erdtman 12 CEPHALOTAXUS:— B fci^7 /#^ •/■:■■ v:--!^ ^c-;t.. . -. .'^'..'■■.■■i.-.'./f Fig. 14. A, Cephalotdxiis dnipacen; a, pollen grain with evaginated tenuitas (lateral view, x 1000); b, pollen grain with invaginated tenuitas (distal face, X 1000). B, C. nana, exine stratification (x 2000). — The drawings for this figure were ready before the electron micrograph, PI. I, Fig. 2, was taken. The white counterpart ("endonexine") to the lamellar layer in the EMG is clearly seen. Superimposed on the "endonexine" is a l)lack layer ("ecto- nexine") corresponding, it would seem, to the granular part of the "nexine" shown in the EMG. Also with regard to sexine details there is an obvious similarity between P'ig. 14 and the EMG, PI. I, Fig. 2. CHAMAECYPARIS:— Megaspore membrane: Chamaecyparis lawsoniana, see Fig. 36, p. 23. Pollen grains: Chamaecyparis pisifera, see Fig. 42 A, p. 26. CRYPTOMERIA:— Fig. 15. Cryptonieriajaponica. From left to right: pollen grain in lateral view, surface (x 250); pollen grain (distal face invaginated) in lateral view, surface and optical section (x 1000); exine stratification ( x 2000). CUNNINGHAMIA: Fig. 16. Cunninghamia lanccolata. From left to right: distal face (upper detail- figure; X 250), LO-patterns (lower detail- figure); lateral view, surface and optical section (distal face invaginated; x 1000); exine stratification ( x 2000). PI. I. Fig. 1. Cednis (dlantica, section through j)art of an acetolyzed pollen ^vall. The nexine has been splil olT from the sexine at the ])oint indicated by tlie arrow. The endonexine is laminated. < 18,000. The black horizontal line indicates 1 ^i. (EMG; from Afzelins, in (irana palynologica, 1: 2, 1956.) i •% Fig. 2. Cephalot(t.viis luiiui, exine stratification, x 42,000. The black hori- zontal line indicates 1 u- (FMG; from Afzelins, in (irana palvnologica, 1: 2, 1956.) 13 CUPRESSUS: Megaspore meinl)rane: Ciij)rcssus arizonka, see Fig. 37, p. 2\\; C. whitlcijana, see Fig. 38, p. 24. CYCAS (see also Fig. 31 B, p. 20):— Fig. 17. Cycas rcvohitn; outline of transverse median section (upper detail- figure); proximal face (lower detail-figure). Fig. 18. Cycas revohita, sections through part of acetolyzed pollen walls: cf. tangential, + oblique section (left); + radial section (right; x 34,000). The black horizontal line indicates 1 pi- EMG B. M. Afzelius. DACRYDIUM:— Megaspore membrane: D. ciipressimiin (Fig. 19). Pollen grains: D. araucarioides (Fig. 20 B), D. bidivillii (Fig. 21), D. ela- tum (Fig. 20 A), D. falcifonne (Fig. 22), D. fonkii (Fig. 23), D. franklinii (Fig. 24), D. guilkmminii (Figs. 25 and 26), D. taxoides (Fig. 27). 14 Fig. 19. Dacrydiiim cupressiiuim; megaspore membrane (x 2000) and LO- patterns of same. Fig. 20. A, Dacrydiiim elatiim; exinc stratification in proximal aposaccium (X 2000) and pollen grain in lateral, longitudinal view (sm-face; nexine contom-s indicated by broken lines; x 1000). B, D. araiicarioides; pollen grain in lateral, longitudinal view (surface; distal face invaginated as indi- cated by the broken line just below the centre of the figure; x 1000); a, proximal face (x 250); b, distal face (x 250). 15 1^. <-"— ■•,'1 ">•'/.•.,!■, .■ . • . ■■•■ iJ!;^^;;,Vv^--^■ Fig. 21. Dacrydinin hidiuillii; distal face (left) and pollen grain in lateral, longitudinal vie^v (surface, optical section, and LO-patterns). x 1000. Fig. 22. Dacrydhim falciforme; a, lateral view; b, proximal face, x 1000. 16 Fig. 28. Dacrydium fonkii; up- per figure: outline of pollen grain in lateral, longitudinal view (x 1000). Lower figure: distal face, surface and optical section (x 1000). For explana- tion of numerals see Fig. 2, p. 7. The curved broken line in the extreme right part of the lower figure indicates the ap- proximate delimitation of a concavity in the distal face of the saccus. Fig. 24. Dacrydium frankUnii; a, lateral, longitudinal view; b, proximal face; c-d, ± deviating grains (c distal, d proximal face); e, LO-patterns; f, exine stratification, laroximal face (x 2000; a-d x 1000). 17 >"'"% % ■ M ■ "'j^.'.v!^"'- ■•;■>.■•;:'■'■/ 1- • . * .i '^ ■' Fig. 25. Dacrydiiim giiilldiinnnii. From left to right: lateral view (x 250); distal face (x 1000); LO-patterns at high and successively lower focus. Fig. 26. Dacrydiiim giiillauminii; oblique view (slightly > x 1000). 18 Fig. 27. Dacrydium taxoides. Upper figure: pollen grain in lateral, longitudinal view, surface and section. Lower ligure: proximal face, sur- face (left) and optical sec- tion (right; x 1000). Lower left-hand detail-figure: out- line of pollen grain in 1 ateral, transverse view( x 250; outer contour of the corpus inark- ed by the broken line). For explanation of numerals see Fig. 2, p. 7. DIOON: Fig. 28. Dioon ediile; upper left- hand detail figure: median sagit- tal section; lower left-hand detail- figure: frontal section; upperright- hand detail-figure: transverse sec- tion (all X ioOO); lower right- hand detail-figures: exine strati- fication (X 1000) and LO-pat- terns. DISELMA:— Fig. 29. Diselma archeri; surface and optical sec- tion (X 1000); exine stratification (x 2000); LO- patterns. 19 EPHEDRA [Fig. 30 A, B, Fig. 31 A, PI. II (facing p. 20)], WELWITSCHIA (Fig. 30 C):- h^ Fig. 30. A, Ephedra antisyphilitica; uppermost detail-figure: section through the exine along line x-y in the main figure ( x 2000); b, LO-patterns; the detail-figure (■< 2000) between this figure and the main figure (x 1000) shows a section through the exine at one of the short ends. B, E. equisetina; cf. distal face (x 1000), surface and optical section; c, young grain with sulcoid aperture. C, Welwitschia mirabilis; cf. lateral, transverse view ( x 1000), exine stratification (x 2000), and cf. distal face (x 1000); uppermost detail- figure: LO-analysis of part of the exine surface (to be read from left to right); as the two central details show there is a very low and narrow ridge (bright in the second, dark in the third detail from the left) at the bottom of the valleys (sti])pled in the extreme left, white in the extreme right detail) separating the hollow sexine ridges (white in the extreme left, stippled in the exti'eme right detail). 20 Fig. 31. A (main figure): Ephedra monosperma; section through an acetolyzed pollen wall, x 19,000. B (lower right-hand corner): Cycas reuohita; section through part of an acetolyzed pollen wall, x 35,000. The black horizontal lines indicate 1//. (EMG; from Afzelius in Grana palynologica, 1:2, 1956.) PI. II m WW f% # .1^'^ ' / r 1 Ephedra niuiwspenud; seclion through j)arl of tlu- iniuT laniinalcd layer of an at-etolyzed ])ollen ^valI (the inner part of the pollen grain is to the left; the black horizontal line indicates 1 /^i). x 93,()0(). (EMG; from Afzelius in (irana palynologica, 1: 2, 1956.) FITZROYA: see Fig. 42 G, H, p. 26. GINKGO: 21 I I Fig. 32. Ginkgo biloba; extreme left (letail-figure: pollen grain in lateral, longitudinal view with an outline of the accompanying median transverse section. Second detail-figure from the left: pollen grain sUghtly tilted with the entrance to the concavity which lotlges the tenuitas shown to the left. The remaining figures exhil)it the distal face of an unexjjanded and an ex- ])ande(l grain. The lower detail figure of the latter gives the outline of a pollen grain in lateral transverse view (owing to an omission a full line uniting the upper extremities of the figure is not shown), x 1000. GLYPTOSTROBUS:— Fig. 33. Ghjptostrohiis pensilis. From left to right: opened gi'ain (x 250); lateral view, surface and optical section (x 1000); exine stratification ( X 2000); LO-patterns. Uppermost detail-hgure: tenuitas (optical section; X 2000). 22 GNETUM: A M X ;'-' ^:.,\ ^&0 <^ X 0^ ■'■■■■!/ k0 » 0 Fig. 34. 'A, Gnetum venosum. — B, G. africaimm. — C, G. montamim. (From Erdtman in Bot. Notiser 1954.) Fig. 35. Gnetiim montanum, section through part of an acetylyzed, very compressed pollen grain. To the extreme right is a spinule. The black hori- zontal line (indicating 1 fx) is drawn within the lumen of the grain, x 21.000. EMG B. M. Afzelius. JUNIPERUS, ARCEUTHOS, CHAMAECYPARIS, CUPRESSUS, FITZROYA, LIBOCEDRUS, WIDDRINGTONIA:— Megaspore membranes: Chamaecyparis laivsoniana (Fig. 36, p. 23), Cu- pressus arizonica (Fig. 37, p. 23), C. whitleyana (Fig. 38, p. 24), Juniperus communis (Frontispiece and Fig. 39, p. 24), J. sabina (Fig. 41, p. 25). Pollen grains: Arceuthos drupacea (Fig. 42 B, p. 26), Chamaecyparis pisifera (Fig. 42 A), Fitzroya cupressoides (Fig. 42 G, H), Juniperus californica (Fig. 42 D), J. prostrata (Fig. 42 E), Libocedrus decurrens (Fig. 42 F), Widdring- tonia cupressoides (Fig. 42 C). 23 Fig. 36. Chamaecyparis lawsoniana; niegaspore membrane (surface), phase contrast. < 4000. (From von Liirzer in Grana palynologica, 1: 2, lO-ifi.) Fig. 37. Cupressus arizonica; megaspore membrane (surface), phase contrast. X 4000. (From von Liirzer in Grana palynologica, 1: 2, 1956.) 24 Fig. 38. Ciipressus whillcyamr, megaspore meml)rane (surface), phase con- trast. X 4000. (From von Liirzer in Grana palynologica, 1: 2, 1956.) Ji^^-:'s.Ti Fig. 39. Jiiniperm communis; megaspore membrane (optical section). >: 1000. (For LO- patterns ot the menil)rane surface, see Frontispiece.) 25 s * t. » 4*. «* 4t % Fig. 40. Jiiniperns snhina; megaspore membrane (optical section), phase contrast. -< 4000. (From von Liirzer in Grana palynologica, 1:2, 195(3.) *,"* ♦ ft # • t Fig. 41. Jiiniperus sabina; megaspore membrane (surface), phase contrast. X 4000. (From von Liirzer in Grana palynologica, 1: 2, 1956.) 26 Fig. 42. Cupressaceae. A, Chamaecyparis pisifera. B, Arceuthos drupacea. C, Widdringtonin cupressoides. D, Jiiniperus californica. E, J. prostrata. F, Libocednis decurrens. G, H, Fitzroya cupressoides. — The main figures (X 1000) exhibit grains in lateral view with (in A-C, and F-H) the distal pole at the top. An aperturoid spot is faintly marked in the upper left-hand (luadrant in D. The detail figures show the exine stratification enlarged 2000 times. The detail-figures between the main figure and the LO-patterns in E show an irregular grain (upper detail-figure) and an opened grain (both X 250). H is a Fitzroya pollen grain of ± normal type whereas in G a deviating, ± "subsaccate'"' gi'ain is shown. — Pollen grains of other cupres- saceous plants are shown in Figs. 4 {Actinostrobus), 11 (Callitris), 29 (Diselnm), 49 {Neocallitropsis), 54 (Pilgerodendron), and 71 (Thujopsis). KETELEERIA: 27 Fig. 43. Ketelccria davidiaud; lateral, longitudinal view and distal face (x 1000). For explanation of numerals see Fig. 2, p. 7. (From lu'dtman in Svensk bot. Tidskr. 1954.) 3-565617 G. Erdtman 28 LARIX: Megaspore membrane: Larix occidentalis (Fig. 44). Pollen grains: Larix decidua f. polonica (Fig. 45 B), L. (jmeUni y&r. japonica (Fig. 45 A), L. occidentalis (Fig. 45 C). Fig. 44. Larix occidentalis; acetolyzed megaspore wall, optical section (above) and surface (below), x 1000. B Fig. 45. A, Larix gmelini var. japonica; exine stratification and LO-patterns. B, L. decidua f. polonica; exine stratification and "LO-patterns". C, L. occi- dentalis; lateral view, surface and optical section (x 1000). LIBOCEDRUS: see Fig. 42 F, p. 26. MACROZAMIA: 29 Ik] d^ Fig. 46. Macrozamia spiralis; a, transverse, equatorial view (optical cross- section); b, distal face; c, exine stratification at amb at right angles to central part of the sulcoid tenuitas; d, pattern caused by endosexinous rods (phase contrast); e-g, morphological variants, a, b x 1000, c x 2000, e-g x 250. METASEQUOIA:— Fig. 47. Metasequoia glyptostroboides; lateral view (x 1000) and exine strati- fication (X 2000). 30 MICROCACHRYS (Fig. 48 A), MICROSTROBUS (Fig. 48 B):— a Fig. 48. A, Microcachrys tetragona; a, oblique lateral view (outline; the sexine of the proximal face in the upper right half part of the figure should be thinner); b, proximal face (x 1000). B, Microstrobus (Pherosphaera) fitzgeraldii; c, lateral view (outline); d, distal face; e, proximal face (outline; X 1000). MICROSTROBUS: see Fig. 48 B. NEOCALLITROPSIS:— 49. Neocallitropsis arcnicarioides. Main surface and optical cross-section (X 1000). Details: opened and unopened grains (x 250); exine stratification (x 2000). Fig. figure: 31 NOTHOTAXUS: Fig. .■)(). Xothotaxiis chienii. From left to right: lateral view, surface and optical section ( < 1000); cxine stratification (x 2000); LO-patterns. PHEROSPHAERA: see Fig. 48 B, p. 30. PHYLLOCLADUS:— Fig. 51. Phyllocladus protractus; a, lateral, longitudinal view of a pollen grain (x 500) with the proximal face covered by a "saccus" (z), possibly an artificial feature resulting from the loosening of the sexine from the nexine; b, g, lateral (longitudinal and ti'ansverse) view (surface); c, f, same as b and g, in optical section; d, distal face ( x di = distal pole); e, proximal face (x pr = proximal pole). — b-g x 1000. 32 PICEA:— Megaspore membrane: Picea ahies (Fig. 52). Pollen grains: Picea jezoensis (Fig. iiU). lOLOGlCAL .BORATORY iJ>BRARY WOODS HOLE, MASS. VI H. 0. I. Fig. 52. Picea ahies; part of an acetolyzed megaspore membrane at high (a) and low (b) focus. 33 Fig. 53. Picea jezoensis; lateral, longitudinal view and distal face (surface and optical section; < lOOO); for explanation of numerals see Fig. 2, p. 7. (From lu'dtman in Svensk hot. Tidskr. 1954.) 34 PILGERODENDRON:— Fig. 54. Pilgerodendron iwif'enim. From left to right: two pollen grains ( x 250); distal face (surface and optical section; x 1000); exine stratification ( x 2000); LO-patterns. PINUS:— P. canadensis (Fig. 55), P. excelsa (Fig. 57), P. nmgo (Fig. 56), P. pence (Fig. 55), P. pinea (Fig. 55), P. tlmnhergii (Fig. 58). 50 100,u Fig. 55. Left, Pinus pence (siibg. Haploxylon). Centre, P. canariensis (subg. Diploxylon, sect. Sula). Right, P. pinea (subg. Diploxylon, sect. Pinea). x 250. Fig. 56. Pinus imigo; section through saccus and, in the lower right-hand corner, part of the exine in the proximal face. About x 1000. 35 Fig. 57. Piniis c.rcclsd; lateral, longitudinal view and distal face (surface and section; ■; lUUO). For explanation of numerals see Fig. 2, p. 7. (From Erdtman in Svensk hot. Tidskr. 1954.) 36 Fig. 58. Piniis thimhergii; lateral, longitudinal view and distal face (surface and section; x 1000). For explanation of numerals see Fig. 2, p. 7. (From Erdtman in Svensk hot. Tidskr. 1954.) PODOCARPUS:— P. alpinus var. caespitosus (Fig. 59 C), P. angustifolius var. wrightii (Fig. 59 A), P. hhimei (Fig. (U) B), P. coriaceus (Fig. 59 B), P. dacrydioides (Fig. 60 A), P. minor (Fig. 61 C), P. nagi (Fig. 61 D), P. niibigenus (Fig. 61 B), P. wallichiamis (Fig. 61 A). 37 Fig. 59. A, Podocarpiis angustifolins var. ivrightii; proximal face. B, P. cori- (weiis; distal face. C, P. alpiniis var. caesj)itosus; proximal face, x 250. (OTE^pS^iiaSBisajg -^• .Mn^j ^l / \ ■■^^ -.1. •-. ■ 2A' "^ \ \ VU;.., "n ■ .1 tj ; S b c « ' o 5 » .' » .:'.:.,■ V,; til; Fig. 60. A, Podocarpiis dacrydioides; a, equatorial view (x 250); b, saccus pattern at high focus; c, pattern of distal face at high (upper detail figure) and low focus; above the main figure (x 1000) is an optical section through the exine at the amb (x 2000). — B, P. hhimei; saccus pattern and optical section through the outer wall of the saccus. 38 Ea mM m D Fig. 61. A, Podocarpu.s wnUichiamis; lateral, longitudinal view (contour only; X 250), distal face (x 1000). B, P. niibigemis. From left to right: proximal face (X 250); lateral, longitudinal view (x 1000); LO-patterns (proximal face). C, P. minor; proximal face (x 1000). D, P. nagi; lateral, longitudinal view (x 1000). 39 PSEUDOLARIX: Fig. 62. Pseiidolarix amabilis; lateral, longitudinal view and distal face (sur- face and optical section; x 1 000 ). P'or explanation of numerals see Fig. 2, p. 7. (From Erdtnuin in Svensk hot. Tidskr. 1954.) 40 PSEUDOTSUGA:— Megaspore membrane: Pseadotsmja kixifolia (Fig. 63 d). Pollen grains: Psciidotsuga taxifolin (¥\%. 63 a-c). Fig. 63. Pseudotsiiga taxifolia; a, distal pole (with tenuitas); b, proximal pole; c, part of the microspore exine (optical cross-section, x 2000); d, part of megaspore exine (optical cross-section, x 1000). The upper left-hand detail- figm-e shows the exine of an opened pollen grain ( x 250), the upper right- hand detail-ligure a young pollen grain with markings similar to a "tetrad scar". SAXEGOTHAEA:— Fig. 64. Saxegothaea conspicua; lateral view, surface and optical cross-section (x 1000). 41 SCIADOPITYS: ,_ V *;.':■:>., _ _,. . • ; •- f-V m • ' ■ "w- *i^ ^ w ffi <;sui!^ ..i .J. A .1, ■\ .-■■-■'. i..... :AJ;V-;^- '■^■;:f^'-/^-i--:--': A. .A. m .i^-6iAss4j?i if k... ■'.'■* • - -'■.•.'■■'■ "Tj 'i'V.'.v/;' •;."Cv '•VCi\v •'■/*■■-' W'^k ff /''^■'- M T^^rC^^ ■s. ^^ ^ f ■■'''M ;.; ■> pi '^^ f ^ ./} 4 -X Fig. 73. a-f, Tsiiga forrestii; a, distal face (outline; x 250); b, proximal face (outline of an aberrant grain; x 250); c-e, LO-patterns [c: four spinules (L); d: the same spinules (O) and upper parts of the undulating tegillum (L); e: the fleck near the centre (L) is a small infrategillar hollow, also vaguely shown in d (O)]; f, tegillum. — Left column (g, i, k, m, n): outhne of exine stratification, proximal face ( >' 2000); g, T. diversifoHa; i, T. sieholdii; k, T. diimosa; m, T. chinensis; n, T. pattoniann. — Right column (h, j, 1, f, o): tegillum of the pulfy frill (x 2000); h, T. diversi folia; j, T. sieboldii; 1, T. yiinnanensis; f, T. forrestii; o, T. chinensis. WELWITSCHIA: see Fig. 30 C, p. 19. WIDDRINGTONIA: see Fig. 42 C, p. 26. PTERIDOPHYTA PL III (facing p. 94); Figs. 74-191, MEGASPORES Isoetaceae: Figs. 123-125 (pp. 67, 68). Selaginellaceae: PI. Ill; Figs. 171- Piliilariaceae: Fig. 162 d, p. 87. 173 (pp. 90, 91). ISOSPORES AND MICROSPORES Families (in accordance with Engler's Syllabus, 12. Ed., Vol. 1, 1954): Angiopteridaceae: Fig. 144 A-C (p. 79). Azollaceae: Fig. 85 (p. 50). Christenseniaceae: Fig. 144 D (p. 79). Cyatheaceae: Figs. 78 (p. 47), 96 (p. 56), 112 (p. 62). Danaeaceae: Fig. 144 F (p. 79). Diclvsoniaceae: Figs. 101 (p. 58), 169 B (p. 90), 186 (p. 95). Dipteridaceae: Fig. 103 (p. 58). Equisetaceae: Fig. 106 (p. 60). Gleicheniaceae: Fig. 114 (p. 63). Hymenophyllaceae: Fig. 188 (p. 96). Hymenophyllopsidaceae: Figs. 119, 120 (pp. 65, 66). Isoetaceae: Figs. 126, 127 (p. 68). Loxsomaceae: Fig. 136 (p. 73). Lycopodiaceae: PI. Ill; Figs. 138- 142 (pp. 75-77), 161 (p. 87). Marattiaceae: Fig. 144 E (p. 79). Marsileaceae: Fig. 145 (p. 80). Matoniaceae: Fig. 159 (p. 86). Ophioglossaceae: Figs. 89, 90 (pp. 52, 53). Osmundaceae: Fig. 155 (p. 84). Parkeriaceae:Figs.89, 9()(p]).52,53). Pilulariaceae: Fig. 162 a-c (p. 87). Plagiogyriaceae: Fig. 163 (p. 88). Polypodiaceae: Figs. 74-77, 81-84, 86-88, 91-95, 97-101, 103-107, 109-111, 115-117, 122, 128-132, 135, 146, 147, 149, 151, 152, 154, 156, 158, 164, 165, 167-169, 183- 186, 189-191. Protocyatheaceae: Figs. 79 (p. 47), 113 (p. 71), 134 (p. 72). Psilotaceae: Fig. 166 (p. 89). Salviniaceae: Fig. 170 (p. 90). Schizaeaceae: Fig. 143 (p. 78). Selaginellaceae: Figs. 174-182 (pp. 91-94). Tmesipteridaceae: Fig. 187 (p. 96). 46 ACROSTICHUM:- .^-a Fig. 74. Acrostichiuu aureuiu f. hastaefoliiiin. Sclerine stratification ( >- 2000). a, perine; b, cf. sexine; c, cf. nexine. ACTINIOPTERIS: Fig. 75. Actiniopteris aiistralis. Spore in lateral view (left; x 250); proximal face, surface (a) and optical section (b + c; in b the contours of the verrucae in the distal face are marked; the faint nick in the nexine is quite acciden- tal; X 1000). ADIANTOPSIS: (?) '"mm 'f^^AV^v""'" Fig. 76. Adiantopsis chlorophylla. From left to right: spore in lateral view (X 250); proximal face (x 1000; surface and optical section); LO-patterns. 47 ADIANTUM:— Fig. 77. Adiantum reniforme. Proxi- mal face, surface (left) and optical section (right; x 1000). ALSOPHILA:— ^ "S ■•'.". '■V/.'^^.v-.i'' .3-. 0'i«( i.'vKfiv" Fig. 78. Alsophila glabra; a, sclerine stratification (x 2000); b, spore, lateral view (X 250); c, distal face (x 1000), surface (left) and optical section (right); d^ and do, LO-patterns. AMPHIDESMIUM:— Fig. 79. Amphidesiuiiim bleclinoides. Distal face (X 1000), surface (left) and optical section (right). 48 ANARTHROPTERIS: Fig. 80. Anarthropteris dictyopteris. From left to right: proximal face (x 250); exine stratification (with a query; x 2000); spore in lateral view (x 1000); LO-patterns. ANEMIA: see Fig. 143 G-I, p. 78. ANGIOPTERIS: see Fig. 144 A, p. 79. ARCHANGIOPTERIS: see Fig. 144 C, p. 79. ASPLENIOPSIS: Fig. 81. Aspleniopsis decipiens; a and c, deviating spores; b, normal spore (proximal lace; x 1000). Upper right-hand details: lateral view (proximal face up; x 250); exine stratification (x 2000). 49 ASPLENIUM:— Fig. 82. Aspleninin juondnthes. From left to right: LO-patterns; sclerine stratification (> 2000); spore in lateral view (x 1000). Fig. 83. Aspleniiim hemionitis. From left to right: sclerine stratification (X 2000); distal face (x 1000); LO-patterns. ATHYRIUM:— ' ■''*:»--^ ? -,-.*v ■.■i'v i'^vV- ^■::V TSt;;^: ■,"*■:■■■■ .;??■- . j.r Fig. 84. Athyrinm fili.v-femina. From left to right: proximal face (x 250); sclerine stratification (x 2000); spore in lateral view; LO-patterns. 50 AZOLLA: %.. ':/\j0. ^'^Sv It'-- ■ ^f /■:'■' '■ ' • \^ J V.-. . K;-'- ;. • ■ .'1 fcs .:"!/.-. <^\'i:ii ji> Fig. 85. Azolla filiciiloides, microspores. From above to below: exine strati- fication (X 2000); proximal face (x 1000; spore sm-rounded by perine); spore in lateral view (x 1000). BLECHNUM:— h Fig. 86. Blechnum polmiforme, part of the sclerine (optical section, x 2000). Attached to the inner surface of the exine is a peculiar (abnormal) process leading into the interior of the spore. 51 BOLBITIS:- Fig. 87, Bolbitis tiirrialbae. From left to right: proximal face (x 250); sclerine stratification (x 2000); lateral, longitudinal view (x 1000). BOTRYCHIUM: a note on the spores in B. simplex is found in the caption of Fig. 153, p. 83. BRAINEA: Fig. 88. Brainea insignis. From left to right: lateral, longitutiinal view ( x 250); sclerine stratification (x 2000); proximal face (x 1000); deviating spore (X 250). 52 CERATOPTERIS:— Fig. 89. Ceratopteris siliqiiosa, proximal face (x 1000); upper detail figures (from left to right): distal face (x 250); sclerine stratification (x 2000); lateral view ( x 250) and LO-patterns. 53 Fig. 90. Ceratopteris siliquosa. Sections through acetolyzed sclerine. The sclerine, as shown in b, consists of a thin perine (the outermost gi'anular layer) and a thick exine faintly sulxlivided into cf. sexine (showing + parallel ridges separated by U-shaped valleys) and cf. nexine (of equal thickness throughout). The upper figure (a) intimates that the sexine has a fine (granular) structure, x 700. CETERACH:— a b c d e a b « c d e % Fig. 91. Ceterach officinariim. From left to right: proximal face (x 250); sclerine sti-atification (x 2000); lateral, longitudinal view (x 1000); LO- patterns. 54 CHEIROPLEURIA:— Fig. 92. Cheiropleuria bicuspis; a, proximal face (x 1000); b, sclerine strati- fication (X 2000); c, distal face (x 1000). CHRISTENSENIA: see Fig. 144 D, p. 79. CIBOTIUM:— Fig. 93. Cibotium barometz, proximal face (x 1000). a, lateral view (x 250); h, distal face (x 250). 1 and 2, respectively, are identical. CNEMIDARIA:— 55 ["■»t*f*'^>Wniy Fig. 94. Cnemidaria specioso. From left to right: LO-patterns, distal face (X 1000) and sclerine stratification (x 2000). CRYPTOGRAMMA: Fig. 95. Cryptogramma brunoniana. From left to right: hUeral view (x 250), distal face (x 1000), exine stratification (x 2000). 56 CYATHEA (see also HEMITELIA):- - 7 Fig. 96. Cijathea uestita. a, sclerine stratification ( < 2000); b, LO-patterns; c, distal face (aperture wrongly marked by broken instead of dotted lines); d, laesura (open); e, lateral view ( x 250). CYCLOPHORUS: see PYRROSIA, p. 89. CYRTOMIUM: see PHANEROPHLEBIA, p. 85. CYSTODIUM: see Fig. 169 B, p. 90. CYSTOPTERIS:— "fCA-J :: Fig. 07. (Ajstoplcris /ifujilis. From left to right: sclerine stratification (x 2000); lateral, longitudinal view (x 1000); proximal face (x 250) and LO-patterns. 57 ^'^1' Fig. 98. Cystopteris fragilis f. dickieana. F^rom left to right: proximal face (optical section, x 250); sclerine stratification (x 2()()()); lateral, longitudinal view(x 1000); LO-patterns. DANAEA: see Fig. 144 F, p. 79. DAVALLIA:— Fig. 99. Davallia canadensis. Proximal face (x 250); lateral, longitudinal view (X 1000), and exine stratification (x 2000). DENNSTAEDTIA: Fig. 100. Dennstaeiltia jmnctilobnla. From left lo right: sclerine stratification (X 2000); proximal face, surface and section (x iboO); analysis of laesura. 58 DICKSONIA:— Fig. 101. Dicksonia yoiingiae. From left to right: lateral view (x 250); distal (di) and proximal (pr; smface and optical section) face; LO-patterns. DIPLAZIUM:— Fig. 102. Diplazium proliferum. From left to right: proximal face (x 2oO); sclerine stratification (x 2000); lateral, longitudinal view (x 1000); LO- patterns. DIPTERIS: Fig. 103. Dipteris chinensis. P>om left to right: hiteral, longitudinal view (X 250); distal face (x 1000) and exine stratification (x 2000); LO-patterns. 59 DR YMOGLOSSUM:— Fig. 104. A, Drymoglossiim heterophyllnm, lateral, longitudinal vieWj( x 1000); a, proximal face ( x 250); b and "c, sclerine stratification ( x 2000); c, LO- patterns. B, D. carnosiim, sclerine stratification (x 2000). DRYNARIA: Fig. 105. Dnjnaria forliinei. From left to right: proximal face (x 250); sclerine stratification (x 2000); lateral, longitudinal view (x 1000); LO- patterns. 5-565617 0. Erdtman 60 DRYOPTERIS: Fig. 106, Dryopteris filix-mas. From left to right: proximal face (optical section, x 250); sclerine stratification ( x 2000); equatorial, longitudinal view (X 1000). ELAPHOGLOSSUM;— &" m ■':■»/ 1.,' f W> y^ •'i '. !•■*; l:\ /" ' »■ >. Fig. 107. Elapboglossiim uicillardii. From' left to right: proximal face (optical section, x 250); lateral, longitudinal view (x l(j()0); sclerine stratification (X 2000). EQUISETUMr— Fig. 108. Eqiiisetum giganteiim. a, part of sclerine of an acetolyzed spore, op- tical cross-section (x 1000); amplec- tators ("elaters", "hapters") dissolved; b, sclerine stratification ( x 2000); c, opened spore (x 250); d, part of an abnormal spore tetrad (one large, three small spores; x 250). GRAMMITIS; k: ;*•""'*■ ,'V tin Gl Fig. 109. Grammitis deplanchei. From left to right: lateral view (X 250); proximal face (x 1000); LO-patterns. GYMNOGRAMME: Fig. 110. Gymnogramme (Eriosoriis) congesta. From left to right: distal face (x 1000); lateral view (x 250); cf. perine fragments (optical section, X 2000); proximal face (x 1000) and LO-patterns. HEMIONITIS: Fig. 111. Hemionitis nrifolia. From left to right: lateral view ( X 250); sclerine strati- fication ( X 2000); proximal face (X 1000). 62 HEMITELIA: Fig. 112. Hemitelia maxonii. From left to right: lateral view (x 250); proxi- mal face (surface and optical cross-section, x 1000); sclerine stratification (X 2000). From Erdtman in Potonie, Svensk hot. Tidskr. 1954. Fig. 113. Hemitelia setosa. From left to right: lateral view (x 250); distal face, smface and optical cross-section (x 1000); sclerine stratification (X 2000). 63 HICRIOPTERIS (Fig. 114 C), PLATYZOMA (Fig. 114 D), STICHERUS (Fig. 114 B), STROMATOPTERIS (Fig. 114 A):— A^ rrmmtimrvton^ir: lOu r^\f'^'\ ',v.j:A.'«.-y-'.'..iy,-.~i'».:<;ti -"10,1 Fig. 114. Gleicheniaceae. A, Stromntopteris moniliformis, sclerine stratifica- tion. B, Sticherus penniger, sclerine stratification. C, Hicriopteris laevissima; Ci, proximal face; Cg, distal face; Cg, part of laesura (optical cross-section), C^, LO-patterns of same. D, Platyzoma microphijUum, sclerine stratification. — A, B, D X 800, Ci and Cg 1000, Cg X 4600. HISTIOPTERIS:— Fig. 115. Histiopteris incisct; proximal face (x 250) and lateral, longitudinal view (optical cross-section and surface; x 1000). 64 HOLTTUMIELLA:— Fig. 116. Holttiimiella flaheUivenium. Three spores of a tetrad still slightly adhering, x 700. HUMATA: Fig. 117. Hiinmta gaunardiana. From left to right: lateral, longitudinal view (X 250); proximal face (x 1000); sclerine stratification (x 2000). HYMENOGLOSSUM: see Fig. 188 C, p. 96. 65 HYMENOLEPIS: m a i if IB- ■ iSi Fig. 118. Hymenolepis spicata. From left to right: lateral, longitudinal view (x 250); distal face (x 1000); a-c, exine stratification showing the successive increase in thickness ( x 2000); LO-patterns. HYMENOPHYLLOPSIS (Figs. 119, 120):— '^ Al^^}%/ iMg. 119. HywenophijUopsis asplenioides, proximal face, surface and optical cross-section (x 1000). In some spores the sclerine stratification appears as indicated at a, and in other spores as indicated at b. 66 Fig. 120. Hymenophyllopsis dejecta; distal face (surface and optical cross- section). X 1000. HYMENOPHYLLUM (see also Fig. 188 C, p. 96): ' 5 II Fig. 121. A, Hymenophyllum recurimm; lateral view (x 250) and proximal face, surface and optical cross-section ( x 1000). B, H. peltatiiin, exine strati- fication ( X 2000). 67 HYPOLEPIS: 4 4j ■ -1 11 13 "• * " 1 r. m^ A B C D Fig. 122. Sclerine stratification in Hypolepis. A, H. repens. B, H. temiifolia. C, H. rugosula. D:a, H. distans. ( x 2000). — LO-patterns at liigh (left) and low (right) focus in H. distnns arc shown in D:l). ISOETES:— Megaspores: Isoetes duriein (Fig. 123), /. echinosponim (Figs. 124, 125). Microspores: Isoetes adspersa (Fig. 126), /. baetica (Fig. 127). Fig. 123. Isoetes diirieui, part of megaspore wall (section), x 1000. Fig. 124. Isoetes echinosponim; part of megaspore wall (optical section). The inner contour of the sIHcified perine is faintly seen left and right of the cf. sexinous outgi'owth in the centre of the figure. The "sexine" is underlain by thinner "nexine". x 2000. 68 \ •—-?•* ^ ^ ^^p ^P P^ fe^^^*^ ^^^ ^^M ^fe^ ~w^ ^^p ^m ^£ [ %» r i, j^fer^«j>^^ ^^ Hhj^^S T^^aSM ■- \W-'^ ^^^^(Jral »PP^ ^^^m i M' *^i^ 'fifM^^BTB Mm ^^oV^ii J^¥^^^m ^\ oS' r J ' '■^L Kk^^!^ l^iSIf iTv' ^ ^ ^J l?i^'' 1. ^**fu ■!i^v .■"''«. Fig. 125. Isoetes echinosponun, acetolyzed megaspore embedded in glycerine jelly (x 125). In some places the spiny perine is faintly shown. Fig. 126. Isoetes adspersa; sclerine stratification and LO-patterns. A thin cf. perine with hollow, tapering processes, open at top (OL), is un- derlain by an exine consisting of a tegillate and baculate sexine (LO = bacula) and nexine. Fig. 127. Isoetes Imetica. a, lateral, longitudinal view (surface); b, lateral, longitudinal view (optical section); c, lateral transverse view (optical section); c, lateral transverse view (optical section); d, polar view (proximal face; sculptine not included); c, exine from a young spore with sexine still adhering to the nexine; x 4000 (a-d x 1000). 69 ISOLOMA: Fig. 128, Isoloma diuergens. From left to right: proximal face (x'ioO); lateral, longitudinal view (x 1000); exine stratification. JAMESONIA:— Fig. 129. Jamcsoiiia imbricata; proximal face, surface and optical section (X 1000). LASTREA: J^'^ M- J,^J■^4 S ^^xJt-r. :^if;4^fe ^k;:i^^js^ >;0' Fig. l.'JO. Ldslrcd llich/plcris. From left to right: proximal face (x 250); sclerine stratification ( 2000); lateral, longitudinal view (x 1000); LO- patterns. 70 LEPTOLEPIA:— ^li^^iiftii-i'^iliiiE^ Vv.. ■■■'■' .-•■■:' e ^ ^■iiiiii J:S;v;; Fig. 131. Leplolepia novae-zelandiae; proximal face (x 1000). — a, equatorial view ( X 250); b, proximal face of monolete spore ( x 250); c, sclerine stratification showing perine (densely dotted) on the outside of the exine; d, proximal pole at various focuses from high (above) to low; e, general surface of spore at different focuses. — N.B. Exceptionally, the "verrucae" in the main figure are shown at low focus (i.e. dark), and not, as otherwise in this book, at high focus (bright). LEPTOPTERIS: see Fig. 155 G, p. 84. LINDSAEA:— ■■■lifer- Fig. 132. Liiidsaea orhiculata. From left to right: lateral view and proximal face (both x 250); distal face (x 1000); LO-patterns. 71 LOPHOSORIA (Figs. 133, 134):— Fig. 133. Lophosoria qimdripinnatn (Puerto Rico; Sintenis 1333, ex herb. Paris); lateral view (surface and section) and proximal face (x 1000). At top, from left to right: distal face ( x 250), LO-patterns, sclerine stratification (X 2000). 72 \vi^^ '•' -'"'.',;' \ '■• '^ymf^ ^^,^^_y !'.:''-'f^-yr--^.^.jry/f.'!-yf? \ ■»•'-- ■r'.--*s^ Fig. 134. Lophosoria quadripinnata. Upper figures (Weberbaiier 1333; ex herb. Berlin), from left to right: proximal face ( x 250); lateral view ( x 1000); sclerine stratification ( x 2000). Lower figures: proximal face of a Lophosoria spore found in a slide made from Serpyllopsis caespitosa var. densifolia (collected by C. Skottsberg in the Juan Fernandez Islands August 27th, 1908); a, sclerine stratification (x 1000); b, lateral view (x 250); c, distal face (X 250). LORINSERIA:— 73 Fig. 135. Lorinserin areolata. From loft to right: proximal face (x 250); lateral, longitudinal view ( < 1000); exine stratification (perine not con- sidered; X 2000). LOXSOMA: MARINE BIOLOGICAL LABORATORY LIBRARY WOODS HOLE, MASS. W. H. a L ^ Fig. 136. Loxsoma cuniiinyhamii. From left to right: lateral view (x 250); sclerine sti'atifi cation (x 2000); proximal face (x 1000); LO-patterns. 74 LOXSOMOPSIS:— j,^v V^=^W Fig. 137. Loxsoiuopsis lehmannii. Lateral view (x 250), distal face (x 1000), and LO-patterns. At top sclerine stratification (x 2000). i ,0 M ' «*<-«cJir>jj' "ttm-. LYCOPODIUM:— L.clavatum [PI. Ill (facing p. 94); Figs. 138 B, 142], L. densiim (Fig. 139), L. diaplianuin (Fig. 138 A), L. drummondii (Fig. 140), L. insidare Fig. 141). Fig. 138. A, Lycopodiiim diaphanum; a + b, distal face (a, at high, b, at low adjustment of the microscope; the different foci correspond to levels a^ and bj in Fig. A: d; c, proximal face (main part of figure: surface view at high adjustment; upper right-hand part: section through the exine; d and e: out- line of exine stratification at distal pole, e at the ecjuator). — B, L. clavatum: detail corresponding to that in L. diaphanum shown in Fig. A: e. — x 2000 (A: a-c), X 4000 (A: d and e; B), x 500 (lower left-hand detail figure= spore of L. diaphanum in lateral view, distal face up). — From Erdtman in Afze- lius, Erdtman and Sjostrand, Svensk bot. Tidskr. 1954, 75 1 1 // // // '/ II \\ \.v ry II II O ^' :i OO :C5-v.f Fig. 139. Lijcopoduun densiim; a, distal, b, proximal face (both x 1000); lower right detail-figure: part of exine surface at the transition between the distal and the proximal face. ^^ p^ $<■''■ -^ Fig. 140. Lycopodiiiiu driimmondii; a, distal, b, proximal face (x 1000); c, part of laesura at different adjustments of the microscope from high to low. Fig. 141. Lycopodium insidare; distal face (x 1000) and LO-patterns. >-.**^:. 1 Fig. 142. Lyco})0(liuin claudtiun; section througii an acetolyzed spore wail (x 125,000) exliil)iting tlie fine, granular-lamellar, structure of tlie outer part of the exine. The distinct lamellae shown in this figure are multiples of fine lamellae (thickness 50-60 A). Each of these consists of a single layer of granules. EMG B. M. Afzelius. (From Grana palynologica, 1: 2, 1956.) 78 LYGODIUM (Fig. 143 A-D), ANEMIA (Fig. 143 G-I), MOHRIA (Fig. 143 J), SCHIZAEA (Fig. 143 E, F):— A r - _..,.v-.. ■*''«>'«>«'«i»ji'.-»i#«ji*^j;iii^-J,:i". /T^-' G/ 70 H M J •:\:'y':.'u'. \ \ If ♦ > ?rtr?.*^.t?.'tT^".Tt* •■*■•*-*•*■•■ *M 20^ Fig. 143. Schizaeaceae, sclerine stratification (x 2000). K, Lygodinm circin- natiim. B, L. vohibile. C, L. micans. D, L. japonicum. E, Schizaea fluminensis. F, 5. melanesica. G, Anemia phyllitidis. H, A. adianti folia. I, A. anthrisci folia. .T, Mohi'ia caffroriim. (From Erdtman in Svensk hot. Tidskr. 1954.) MACROGLENA: see Fig. 188 B, p. 96. MACROGLOSSUM: see Fig. 144 B, p. 79. MARATTIA (Fig. 144 E), ANGIOPTERIS (Fig. 144 A), ARCHANGIOPTERIS (Fig. 144 C), CHRISTENSENIA (Fig. 144 D), DANAEA (Fig. 144 F), MACRO- GLOSSUM (Fig. 144 B):— 79 Fig. 144. Marattiales. A, Angioptcris longifolia; proximal face (surface and optical section; x 1000). B, Macroglossuin alidae; proximal face (surface and optical section; x 1000); C, Archangiopteris henryi; proximal face (sm-- face and optical section; x 1000). D, Christensenia aesciilifolia; proximal face (surface and optical section; x 1000); to the left two spores in lateral, trans- verse and lateral, longitudinal view (x 250). E, Marattia fraxinea; proximal face (surface and optical cross-section; x 1000); to the left two spores in transverse lateral and in longitudinal lateral view (x 250). F, Danaea elliptica; lateral, longitudinal view (x 1000), proximal face (x 250) and sclerine stratification (x 2000). (From Erdtman in Svensk hot. Tidskr. 1954.) 80 MARSILEA: '''■f''f'i'-]''i'^Vfi:] Fig. 145. Ma IS He a aegyptiaca, microspore. From left to right: lateral view (x 250); proximal face (surface and optical section; X 1000); sclerine stratification (X 2000) and LO-patterns. MATTEUCIA:— JjAi B d^ Fig. 146. A, Matteiicia struthiopteris; a, proximal face (x 250); b, lateral, longitudinal view (surface and optical section; x 1000); c, sclerine strati- fication ( X 2000); d, LO-patterns. B, M. orientalis, LO-patterns. MICROLEPIA:— Fig. 147. Microlepia hirta. From left to right: lateral view (x 250); sclerine stra- tification ( X 2000); proximal face ( x 1000); LO-patterns. 81 MOHRIA: see Fig. 143 J, p. 78. NEGRIPTERIS:— > m N u V '^ \ii Jkil J^^-r^ • T:^'f ^ *>-■■ .V' S^"^' Fig. 148. Negripteris incann. From left to right: scleriiie stratification ( x 2000); distal face (surface and optical section; x 1000); LO-patterns. NEPHROLEPIS: ,.v" Fig. 149. Nephrolepis cordi folia. From left to right: proximal face ( X 250); lateral, longitudinal view (X 1000); sclerine stratification; (X 2000). OLEANDRA:— ^-'^ ^ >■ ..-•i»' n M J- Fig. 150. Oleandrd neriiformis. From left to right: proximal face (x 250); lateral view (median optical section; x 1000); sclerine stratification (x 2000). 82 ONOCLEA:— ^>.->v-- :SQ,C Fig. 151. Onoclea sensibilis. From left to right: lateral, longitudinal view (X 250); proximal face (surface and optical section; x 1000); sclerine stratification; x 2000); LO-patterns. ONYCHIUM:— Fig. 152. Onychiiiin japoniciim. P>om left to right: sclerine sh'atification (X 2000); proximal face (x 1000); lateral view (x 1000). OPHIOGLOSSUM: 83 K L M Fig. 153. Ophioglossum coriaceum. Main figure: proximal face (x 1000), surface and optical section; a-d, sections through the exine ( x 2000; a, b, and c are sections along the lines klin, ikno, and op in the main figure (kim corresponds to the letters KLM in fig. a etc.) whereas d exhibits a part of the exine with the sexine locally severed from tlie nexine (in Botrycliinm simplex transitions have been seen from spores with the sexine adhering to the nexine, as in the main figure above, to sucli where the sexine is almost completely separated from the nexine — due to tlie chemical treatment^ imparting a + pansaccate appearance to the spore); e-g, LO-patterns at high, medium, and low focus. Between d and the main figure is as spore seen from the side ( x 250; di, distal, pr, proximal pole). — From Erdtman in Svensk bot. Tidskr. 1954. 84 ORMOLOMA (Fig. 154 A), ORTHIOPTERIS (Fig. 154 R): Fig. 154. A, Ormoloma imrayana; lateral view (x 250), distal face (xlOOO), and sclerine stratification (x 2000). B, Orthiopteris imieqiinlis; proximal face (X 1000), exine stratification (x 2000), and— to the left— spore in lateral view ( X 250) and proximal face of an aberrant spore ( x 250). ORTHIOPTERIS: see Fig. 154 B. OSMUNDA (Fig. 155 A-E), LEPTOPTERIS (Fig. 155 G), TODEA (Fig. 155 F):— I 10/U pum "• .1 fiiii '■ ■■■■•■ ■ ' m :\-'.^^'^''^:^^'^^^^^^ B D Fig. 155. Osmundaceae, exine stratification (x 2000). A, Osmunda cinna- momea, part of exine in proximal face (with laesm-a). B-G, part of exine in distal face; B, Osmunda regalis (subgen. Euosmunda); C, 0. banksiifolia (subgen. Pleasiiim); D, 0. cinnamomen (subgen. Osmundastrum); E, 0. claytoniana (subgen. Osmundastrum); F, Toden barbara; G, Leptopteris superba. 85 PELLAEA: Fig. 156. PelldCd oiridis. From left to right: proximal face (x 250); sclcrine stratification (x 2000); lateral view (x 1000); LO-patterns. PERANEMA:- Fig. 157. Peranema cyatheoides. From left to right: proximal face (x 250); sclerine stratification (x 2000); spore in lateral, longitndinal view (x 1000); LO-patterns (OL-pattern due to small perforations in the perine). PHANEROPHLEBIA:— .^^<^f^ o o ,-;i*^^. Fig. 158. Plianernphlebia caryofidea. From left to right: proximal face (x 250); spore in lateral, longitudinal view (surface and optical section; x 1000); LO-patterns; sclerine stratification ( x 2000). 86 PHANEROSORUS: ■A \ \ •■•■■^ X \\ v.-.^'i. V -V ^ \l!U;S:M XV. -^ X V X jiliSfl -^ ^::v. N W&% ^^-"^'^ \ """"' n"^ 1 '^-^ // >' •/ /j ' J / Fig. 159. Phnnerosonis major; a, proximal face, surface and optical sections (x 1000); b, spore in lateral view (x 250); c, monolete spore, proximal face (X 250). The LO-pattern in the lower right-hand corner is due to the thin perinous cover. PHLEBODIUM:— >^ 2 50 - 250 xlOOO X2000 Fig. 160. Phlehodiiim aiireiim; a, spore in lateral, longitudinal view; b, proxi- mal face; c, part of proximal face with laesura (broken lines); d, exine stratification. 87 PHYLLOGLOSSUM:— Fig. 161. Phylloglossum driim- mondii; lateral view ( x 250) and distal face (x 1000). PILULARIA:— Megaspore: Pilularia globiiUfera (Fig. 162 d). Microspores: Pilularia glohuUfern (Fig. 162 a-c). r-- Sty Fig. 162. Pilularia glohulifera. a-c, microspore, a, proximal face (sm-face and optical cross-section; x 1000); b, lateral view (sm-face and optical cross-section; x 1000); c, LO-patterns; d, megaspore, sclerine stratilication (X 2000; cf. also Grana palynologica, 1: 2, 1956, PI. I, Fig. 13, facing p. 126). 88 PLAGIOGYRIA: -' .V, Fig. 163. Plagiogyria henryi. From left to right: lateral view ( X 250); proximal face ( x 250); distal face (x 250); sclerine stratification (x 2000). PLATYCERIUM:— Fig. 1C)4. Platyceriiim madagascariense. From left to right: proximal face (x 250); lateral view (sm-face and optical cross-section; x 1000); sclerine stratification {--^ 2000). PLATYZOMA: see Fig. 114 D, p. 63. POLYBOTRYA:— Fig. 165. Polyhotryn appendiculnta; a, lateral, transverse view (x 250); b, lateral, longitndinal view (snrface and optical section, x 1000); c, proxi- mal face (X 250); upper left-hand detail: sclerine stratification (x 2000). 89 PSILOTUM:— !*- ■■■■i. so 100 It Fig. 166. Psilotnm niidnm; a, laesura (optical cross-section; x 2000); b, lateral, longitudinal view (x 250); c. proximal face (x 250); d, LO-patterns; e, sclerine stratification ( x 2000). PTERIDIUM:- Fig. 167. Pteridium nquilinum. From left to right: lateral view ( x 250); sclerine stra- tification (X 2000); distal face (x 1000). PYRROSIA:— Fig. 168. Pyrrosia abbreuiata, sclerine stratification, (X 2000). SACCOLOMA (Fig. 169 A), CYSTODIUM (Fig. 169 B):— ■§MW:Mm:^^^M / ■''y'.:0^:y M';-A Wrffi :^--^h 'V^^^\ ■ Fig. 169 A. Snccoloma ele- gans; a, sclerine stratifica- tion (p, perinc?; s, sexine ?; n, nexine ?; x 2000); b, part of proximal face (pr, prox- imal pole); c, part of distal face (b and c x 4250). 90 r^i?^^3^ .■--".'>/.' J».W I'.-'";.'"-- V;!* :\ ^>^:.;.;-"*f,: ?^•^:!;.:-•■^^^'-x^^>i >*■:' ^ • •M,. ■* Fig. 188. Hymenophyllaceae. A-C, Tricbomanes and Hymenophylliim, exine stratification (x 2000). A, T. (Selenodesmium) rigidum. B, T. (Macroglena) meifoliiiin. C, Hymenophylliim ( Hymenoglossiim) criientiim. D, Trichomanes (Vandcnboschia) radicans, proximal face ( < 1000); a, exine stratification ( X 2000); b, lateral view ( x 250); c, LO-analysis of laesura. VANDENBOSCHIA: see Fig. 188 D. VITTARIA:— Fig. 189. Vittaria uittarioides. From left to right: lateral view (x 250); proxi- mal face (X 1000); sclerine stratification (x 2000). 97 WOODSIA:— Fi^. 190. Woodsia alpina. From left to right: sclerine stratification ( distal face (x 1000); LO-patterns. X 2000); XIPHOPTERIS:— Fig. 191. Xiphopteris saffordii. From left to right: lateral view (x 250); proxi- mal face (sm-face and optical cross-section; x 1000); exine stratification (X 2000). "... opening several of these dry red Cases, I found them to be quite hollow, without any thing at all in them; whereas when I cut them asunder with a sharp Pen-knife when green, I found in the middle of this great Case, another smaller round Case, between wiiich two, the interstices were fill'd with multitudes of stringie fibres, which seem'd to suspend the lesser Case in the middle of the other, which (as farr as I was able to discern) seem'd full of exceeding small white seeds . . ." From a description of moss capsules in R. Hooke's Micrographia 1667 (pp. 131, 132). BRYOPHYTA PI. IV (facing p. 108), V (facing p. 109); Figs. 192-253. HEPATICAE Aneiiraceae: Fig. 240 (p. 118), Anthocerotaceae: Figs. 194 (p. 100), 208 (p. 106), 225 (p. 112). Blasiaceae: Fig. 197 (p. 101). Cleveaceae: Fig. 204 (p. 104). Codoniaceae: Fig. 213 (p. 108). Conocephalaceae: Fig. 205 (p. 104). Corsiniaceae: Fig. 206 (p. 105). Cyathodiaceae: Fig. 207 (p. 105). Exormothecaceae: Fig. 211 (p. 108). Frullaniaceae: Fig. 214 (p. 109). Grimaldiaceae: Fig. 232 (p. 115). Marchantiaceae: Fig. 209 (p. 106). Monocleaceae: Pig. 226 (p. 113). Oxymitraceae: Fig. 230 (p. 114). Pelliaceae: Fig. 231 (p. 115). Plagiochilaceae: Fig. 233 (p. 116). Radulaceae: Fig. 238 (p. 118). Ricciaceae: Fig. 241 (p. 119). Riellaceae: Fig. 242 (p. 120). Scapaniaceae: Fig. 243 (p. 121). Sphaerocarpaceae: Fig. 216 (p. 109). Symphyogynaceae: Fig. 250 (p. 123). Targioniaceae: Fig. 251 (p. 123). MUSCI Andreaeaceae: Fig. 192 (p. 100). Archidiaceae: Fig. 195 (p. 101). Bryaceae: Fig. 199 A-C, E (p. 102). Buxbaiimiaceae:Fig.200A,B(p.l02). Calomniaceae: Fig. 201 (p. 103). Calymperaceae: Fig. 202 (p. 103). Catascopiaceae: Fig. 224 D (p. 112). Dicranaceae: Fig. 203 B (p. 103). Diphysciaceae: Fig. 200 C (p. 102). Ditrichaceae: Fig. 203 A (p. 103). Encalyptaceae: Fig. 210 (p. 107). Ephemeraceae: Fig. 227 (p. 113). Fissidentaceae: Fig. 212 (p. 107). Funariaceae: PI. IV, V. Georgiaceae: Fig. 215 (p. 109). Gigaspermaceae: Fig. 217 (p. 110). Grimmiaceae: Fig. 239 (p. 118). Hedwigiaceae: Fig. 218 (p. 110). Helicophyllaceae: Fig. 219 (p. 110). Hookeriaceae: Fig. 220 (p. 111). Hylocomiaceae: Fig. 221 (p. 111). Lembophyllaceae: Fig. 228 A (p. 113). Leptostomaceae: Fig. 222 (p. 111). Leskeaceae: Fig. 223 (p. 111). Leucobryaceae: Fig. 203 C (p. 103). Meeseaceae: Fig. 224 A-C (p. 112). Mniaceae: Fig. 199 1) (p. 102). Neckeraceae: Fig. 228 B (p. 113). Oedipodiaceae: Fig. 229 (p. 114). Orthotrichaceae: Fig. 253 (p. 124). Pleurophascaceae: Fig. 234 (p. 116). Polytrichaceae: Fig. 235 (p. 116). Pottiaceae: Figs. 193 (p. 100), 236 (p. 117). Rhizogoniaceae: Fig. 237 (p. 117). Schistostegaceae: Fig. 244 (p. 121). Sphagnaceae: Fig. 246 (p. 121). Spiridentaceae: Fig. 247 (p. 122). Splachnaceae: Fig. 248 (p. 122). Symphyodontaceae: Fig. 249 (p. 122). Timmiaceae: Fig. 252 (p. 124). 100 ACROSCHISMA:— >r'OC Fig. 192. Acroschisma wilsonu; a, distal face (x 1000); b, tetrad (x 1000); c, LO-patterns (distal face); d, exiiie stratification (1, in chlorinated spores); X 2000. ANOECTANGIUM:— Fig. 193. Anoectangium aestwiun; spore in lateral view, surface and optical section (distal pole upwards; x 1000); LO-patterns (distal face). ANTHOCEROS: Fig. 194. Anthoccros tiiberciilatm; from left to right: sclerine stratification (X 2000); proximal face (x 825); LO-pattern. 101 ARCHIDIUM:— Fig. 195. Arcliidilun (illernifoliiim; part of spore surface (x 1000). ATHALAMIA: Fig, 196. Athalamia nana; spore (x 1000) and sclerine stratification ( x 2000). BLASIA: Fig. 197. Blasia pusilla; part of spore, surface and optical section (x 1000). BLINDIA: see Fig. 203 B, p. 103. 102 BRACHIOLEJEUNIA:— Pi *v Fig. 198. Brachiolejeunia sandwicensis; part of spore, surface and optical section (x 1 ()()()); sclerine stratification ( x 2000) and LO-patterns. BRYUM (Fig. 199 A, B), CINCLIDIUM (Fig. 199 E), MIELICHHOFERIA (Fig. 199 E), POHLIA (Fig. 199 C):— pp-sv^ B It^HiJ »;*>" .^''• ■''■i;. f * :. • ii ft. . . .■ - t] &ti£^ Fig. 199. Bryaceae (A, B, C, E), Mniaccae (D). — A, Brijiiiu inaminillatnm; part of spore, surface and optical section (x 1000). B, B. caespiticiiim; spore in lateral view (x 1000). C, Pohlia elongata; spore in lateral view (X 1000). D, Cinclidiiim subrotundnm; part of spore, surface and optical section (x 1000). E, Mielichlioferia elongata; cf. proximal face (x 1000). BUXBAUMIA (Fig. 200 A, B), DIPHYSCIUM (Fig. 200 C):— A ''■'. ... 3 B Fig. 200. Buxbaumiales. A, Biixbaumin aphylla. 15, B. viridis. C, Diphyscium foliosum. (A-C x 1000). 103 CALOMNIUM:— gy?;Tyg Fig. 201. Caloiiiniuin laeluiu; surface and optical section ( >- 1000), exine stratification (x 2000) and LO-jjatterns. CALYMPERES:— "^i Fig. 202. Calyinperes afzelii; surface and optical section (x 1000), exine sti-atification ( x 2000) and LO-patterns. CATASCOPIUM: see Fig. 224 D, p. 112. CERATODON (Fig. 203 A), BLINDIA (Fig. 203 B), LEUCOBRYUM (Fig. 203 C):— O Fig. 203. Dicranales. — A, Ceratodon piirpureiis; from left to right: spore in lateral view (x 250); two spores (cf. proximal face; x 1000); LO-patterns. B, Blindia acuta; from left to right: spore in lateral view (x 250); cf. distal face (X 1000); cf. proximal face (x 1000). C, Leucobryiim (jlaucum; exine stratification (x 2000). CINCLIDIUM: see Fig. 199 D, p. 102. 104 CLEVEA:— Fig. 204. Clevea robusta; distal face (x 1000). CONOCEPHALUM:— Fig. 205. A, Conocephahim (Fegatella) coniciun; part of spore ( x 1000), optical section and surface; LO-patterns. B, C. supradecompositum; part of spore (X 1000), surface and optical section (with LO-patterns). CORSINIA:— 105 X 2000 y 2000 xlOO ylOOO Fig. 206. Corsinia marchantioides. a, lateral view; b, sclerine stratification in the less convex face; c, LO-pattern; d, sclerine stratification in the more convex face; e, polar view (less convex face); f^, fg: part of spore in polar view (fi, optical section, fg, surface). CYATHODIUM:— ?>? 2000 Fig. 207. Cyathodiiim ofricanum; sclerine stratification and LO-patterns. 106 DENDROCEROS: ^,^r/Vy^/V, Fig. 208. Dendroceros crispatiis; part of spore surface (x 1000). DIPHYSCIUM: see Fig. 200 C, p. 102. DUMORTIERA:— A J'K. .'^- m7 Kl, Fig. 209. Diimortiera hirsiita; exine stratification (x 2000) and LO-patterns, B, D. vehitina; spore in polar view (x 1000), exine stratification (x 2000), and LO-patterns. ENCALYPTA: 107 pn mm w cm m ^-C.;; di 7 1. Fig. 210. A, Kncniyptd (tlpina. From left to right: sporr in lateral x\v\\(' 'ioO); of. proximal face '( < lOOO); LO-patterns in the distal (?) face. B, E. cHiata; distal face (upper figure) and proximal face (lower figure; both x 1000); the lower right-hand detail shows a spore in lateral view (x 250). C, E. rlmhdocarpa; distal face (upper figure) and proximal face (lower figure; both X 1000); the lower right-hand detail shows a spore in lateral view (X 250). 8-565617 G. Erdtman 108 EXORMOTHECA:— X 250 X1000 50 100 !< P'ig. 211. Ex'ormotheca fimbriata; a, proximal, b, distal face (x 250). The LO-patterns to the extreme right exhibit — at x-y — a part of one of the muroid ridges shown in b, and also the "insuloiis" condition in the bottom of the lumina. ISMJ LJii.i>b: — ^ M ? /r>>:\'- */ 0 ^%: a* if Fig. 212. Fissidens adiantoides; surface and optical section (x 1000), exine stratification (x 2000), and LO-patterns. FOSSOMBRONIA:— Fig. 213. A, Fossombronia angnlosa; spore (x 1 ()()()); a, part of "muri" at high and, in b, at sb'ghtly lower adjustment of the microscope; c, spore, lateral view ( 2r)0); the L()-])atlerns to the extreme left show the patterns at the bottom of the liimina. 13, F. diunortieri; d, exine stratification (with "murus", X 2000); e, spore (proximal face ?), x 250. 109 FRULLANIA:— Fig. 214. FriiUania involvens; surface and optical section (x 1000). FUNARIA: see PL IV, V (facing pp. 130, 131). GEORGIA: «# • > Fig. 215. Georgia pelhicida; from left to right: spore in lateral view (x 250); spore in polar view (x 1000); LO-patterns. GEOTHALLUS: di ? Fig. 216. Gcolhdilus liihcrosiis; A, lateral view (x 250); B, ])olar view (di = cf. distal face, surface and optical section; pr = cf. proximal face, surface, X 250); C, sclerine stratification (about x 2000). no GIGASPERMUM (Fig. 217 B), LORENTZIELLA (Fig. 217 A): B p^-o^ m Fig. 217. Gigaspermaceae. — A, Lorentziella paragiiensis; sclerine stratifica- tion (X 2000) and LO-patterns. B, Gigaspennum repens; sclerine stratification (X 2000) anil LO-patterns. HEDWIGIA (Fig. 218 A), HEDWIGIDIUM (Fig. 218 B):— Fig. 218. Hedwigiaceae. — A, Hedwigia cilintd; from left to right: proximal face (X 250); spore in lateral view {>' 1000); LO-patterns. B, Hedwigidium integrifoliam; from left to right: proximal face (x 250); spore in lateral view (X 1000); LO-patterns. (From Erdtman in Svensk hot. Tidskr. 1954.) HEDWIGIDIUM: see Fig. 218 B. HELICOPHYLLUM:— ij ? Fig. 219. . .^. _^,.. HelicophyUnin torqiuitiiin; a, LO-patterns, proximal face; b, LO- patterns, distal face; the central figure shows the proximal face of a spore, surface (left) and ojitical section (right; x 1000). Ill HOOKERIA: *■»-»■ Fig, 220. Hookeria albicans; spore (x 1000) and LO-patterns. HYLOCOMIUM:— Fig. 221. Hylocomium splendens; the main figure shows the supposed proxi- mal spore face (x 1000). ISOTHECIUM: see Fig. 228 A, p. 113. LEPTOSTOMUM: ^0=a^; Fig. 222. Leptostomiim macrocarpiim; from left to right: spore in cf. trans- verse lateral view (x 250); spore in longitudinal lateral view (x 1000); LO- patterns. Upper detail figure: exine stratification (x 2000). LESKEA: eay Fig. 223. Leskea pohjcarpa; sjiore, sin'face and optical section (x 1000). The left part of the right-hand (h'fail figure shows the LO-patterns of the cf. (iistal face, the rigiit part those of the cf. proximal face. 112 LEUCOBRYUM: see Fig. 203 C, p. 103. LORENTZIELLA: see Fig. 217 A, p. 110. MEESEA (Fig. 224 A, B), CATASCOPIUM (Fig. 224 D), PALUDELLA (Fig. •pr" Fig. 224. Meeseaceae (A-C), Catascopiaceae (D). — A, Meesea longiseta, cf. distal face (left) and cf. proximal face (right; x 1000). B, M. iiliginosa, cf. distal face (left) and cf. proximal face (right; x 1000). C, Pahidella squarrosa, cf. distal face (left) and cf. proximal face (right; x 1000). D, Catascopiiim nigrihim, part of spore (x 1000), surface (left) and optical section (right). MEGACEROS:— Fig. 225. Megaceros aosaniis; a, spore in lateral, slightly obHque view ( x 1000); b, distal face (x 250); c, elater (x 1000; the detail figure shows the wall stratification, x 2000). MIELICHHOFERIA: see Fig. 199 E, p. 102. MONOCLEA:— 113 Q-mm Fig. 226. Monoclea forsteri; spore (x 1000), exine stratification (x 2000), and LO-patterns. NANOMITRIUM:— Fig. 227. Nanomitriiiin teneriim; a, lateral view (x 250); b, outline of tetrad (X 250); C-, proximal face, surface and optical section (x 1000); d, distal face (X 500). NECKERA (Fig. 228 B), ISOTHECIUM (Fig. 228 A):— ^j^yjj A ^ m i^'i-' mi "*\ Fig. 228. Neckerinales. — A, Isotheciiim inyosiiroides; LO-patterns and spore (x 1000); a, surface; b, optical section (upper quadrant without, lower quadrant with, easily detachable "granules"). B, Xcckcra coinphuintd; spore (X 1000), surface and optical section; exine stratification ( < 2000), and LO-patterns. 114 OEDIPODIUM:— •ifSatiiy^^ n '■i^.cM 4.- :..■■ ■■:■■. 'f. % «f' * ^t^m ^^o^ ^A^ Fig. 229. Oedipodiiim griffithianum; a, proximal face, surface and optical section (x 1000); b, distal face (x 250); c, lateral view (x 250); d, LO- patterns; e, sclerine stratification (about '■< 2000). OXYMITRA:— k' ^g^ Fig. 280. O.vijmitra paleacea; a, proximal (?) face, surface (left) and section (right; x 1000); b, spore in lateral view (x 250); c, optical section through a "murus" in the reticulum; d-g, LO-analysis of a "muriferous" part of the spore surface. PALUDELLA: see Fig. 224 C, p. 112. 115 PELLIA: Fig. 231. Pellin epiphijlla; part of a spore, optical section and surface (x 1000); exine stratification ( ' '2000). PHASCUM: see Fig. 236 A, p. 117. PLAGIOCHASMA:— i-a' m :*:•'; '•^■A Fig. 232. Plagiochasma intermedium; a, proximal face (x 1000) and LO- patterns; b, one half of an elater (x 1000). 116 PLAGIOCHILA:— Pf Fig. 233. Plagiochila aspic nioides; spore (surface and optical section, x 1000); LO-patterns. PLEUROPHASCUM:— O b C-^ c Fig, 234. Pleurophascuiu (luadrilobiim; main figure: proximal face (surface and optical section; < lOOU); a, proximal face (x 250) of slightly irregular spores; b, transverse side view (x 250); c, longitudinal side view (x 250, distal pole upwards). POHLIA: see Fig. 199 C, p. 102. POLYTRICHUM: B iS );i>■:,■i^ » « • Fig. 235. A, Polytrichum jiiniperimim (x 1000); a, spore in lateral view (proximal pole upwards); b, proximal face; c, distal face and LO-patterns of the square shown in the centre of the face. B, P. gracile; d, lateral view; e, proximal (tenuitatiferous) face; f, distal face; g, tetrad (x 250; d-f x 1000). 117 POTTIA (Fig. 233 B), PHASCUM (Fig. 233 A):— .'&^ VI" c> cxr- 't* ^ ■■ ■ ^ Fig. 236. Pottiaceae (see also Fig. 193, p. 100). — A, Phasciim ciispidntiim, from left to right: spore in polar view (x 250); spore in lateral view, surface (left) and opti'cal section (right; x 1000); LO-patterns. B-E, surface (x 1000; only a fourth of a hemis])here shown), sclerine slralKication (about x 2000), and LO-patterns in Pottin crinita (B), P. davalliana (C), P. triincata (D), and P. heimii (E). PYRRHOBRYUM:— Fig. 237. Pyrrhobryum spiniforine. From left to right: spore in lateral view (x 250); spore in polar view (x 1000), surface (left) and optical section; LO-patterns. 118 RADULA:— ^^^ Fig. 238. Radiila lindbergiana; surface and optical section (lower right-hand quadrant; -< 1000); exine stratification (x 2000), and LO-patterns. RHACOMITRIUM:— Fig. 239. Rhacomitriiim microcarpon. From left to right: spore in lateral view (X 250); spore in polar view (-< 1000); L()-pattcrns. RICCARDIA:— Fig. 240. RiccanUn Utlifrom; spore (x 1000); exine stratification (x 2000); LO-patterns. 119 RICCIA: Fig. 241. Riccia beyrichiana; main figure: distal face, surface and optical section (left); proximal face, surface (right; x 1000); a, laesura (?); b, spore in lateral view (x 250); c, outline of sclerine stratification (without attempt to classify the layers); d, spore margin (optical section); x-y, approximate limit between distal and proximal face. 120 RIELLA: Fig. 242. A, Riella halopluhi (left). B, R. pnrpureospora (right). The sectors in the main figure (A + B) are as follows (enumerated clockwise, beginning at A): sclerine, optical section; part of proximal (?), tenuitatiferous (?) face; part of distal (?) face; sclerine, optical section; part of jiroximal (?), tenuitati- ferous (?) face; part of distal (?) face. In the lower left-hand detail figure tentative interpretations of the sclerine stratification in R. halophila are ex- hibited. The lower right-hand detail shows an outline of the sclerine strati- fication in R. purpiireospoi'd (the second layer from below should have been blackened in, not dotted); the ()L-pattern is due to reticuloid arrangement of the 'sexinous' (cf. endosexinous) elements in the third layer from below. SCAPANIA:— 121 Pi mi Fig. 243. Scapania pahidicola; part of spore surface (X 1000); LO-patterns. SCHISTOSTEGA: X 4000 -^.isss* Fig. 244. Scliistostega osmnndacea; LO-patterns and live spores ( x 1000; from left to right: optical section, distal face of three spores, and spore in lateral view); the upper detail figure exhibiting the exine stratification is enlarged about 4000 times. SOUTHBYA:— Fig. 245. Soiithbya stillicidioniin; a, cf. distal face; b, cf. proximal face (x 1000). SPHAGNUM:— Fig 24(). A, Spluif/niini fiiiihrialiim; deviating ("tetrachotomolnesurate" or "4-lete") spore (> lOOO). H, S. p(duslrc; proximal face of normal (3-lete) spore (x 1000); a, with perine (surface); h, with perine (optical section); c, without perine (surface). 122 SPIRIDENS:— j(?) Fig. 247. Spiridens aristidifolins; spore in lateral view (x 1000); exine strati- fication ( X 2000). SPLACHNUM (Fig. 248 C), TAYLORIA (Fig. 248 B), VOITIA (Fig. 248 A). B ;« vS i il>^----4 Fig. 248. Splachnaceae. — A, Voitia niualis (>^ 1000). H, Tayloria lingidata; surface and optical section (x 1000), LO-patterns, and exine stratification ( X 2000). C, Splachniim vascidosiim; two bilateral spores (the upper in lateral view, proximal face upwards; the lower in polar view, showing the cf. proximal tenuitas) and one + radiosymmetric spore (x 1000). STROEMIA: see Fig. 253 A, p. 124. SYMPHYODON:— ;:::i Fig. 249. Sympliyodon cclunalus; spore in lateral (?) view ( polar (?) view (x 1000); LO-patterns. X 250); spore in SYMPHYOGYNA:— 123 Fig. 250. Symphyogyna podophylla; four spores (three x 250, one '-< 1000); LO-patterns. TARGIONIA:— ir^'"-^ Fig. 251. TaryionUi hypophylla; from left to right: spore in lateral view (X 250); spore in polar view (x 1000); sclerine stratification and LO- patterns. TAYLORIA: see Fig. 248 B, p. 122. 9-565617 G. Erdtman 124 TIMMIA: B m s** ■ Fig. 252. A, Timmia austriaca; spore in lateral view (x 1000); LO-patterns. B, T. anomala; exine stratification ( x 2000). ULOTA (Fig. 253 B), STROEMIA (Fig. 253 A):— a B - 7 Fig. 253. A, Stroemia gyninostoma; a, spore in lateral view ( x 250); b, distal face (X 1000); c, proVimal face (x 1000); d, tetrad (x 250); e, outline of apertures. B, Ulota bruchii; surface and optical section (x 1000). VOITIA: see Fig. 248 A, p. 122. SUPPLEMENT ON NEW METHODS IN PHYSICAL CELL RESEARCH AND THEIR APPLICATION IN STUDIES OF POLLEN GRAINS AND SPORES BY B. M. AFZELIUS The rapid development in physical cell research has recently provided much news of interest to pollen and spore morphology. Deeper understand- ing of the cell, the morphology and composition of its organellae and their finest constituents down to macromolecular dimensions can be gained through the ever-widening application of refined techniques such as phase contrast and polarization microscopy, ultra-violet light, interference, and electron microscopy. Certain indirect methods are also of interest (e.g. X-ray diffraction) and there are microscopical and other methods for obtaining quantitative cytochemical data. Micrographs of macromolecules can thus be made (cf. Wyckoff 1949, p. 189) and it is even possible (cf. e.g. Frey-Wyssling 1954) to determine the macromolecular or particle weight by microscopical methods. From a study of electron micrographs (Stein- mann in Finean, Sjostrand, and Steinmann 1953) of the small spherical particles constituting the lamellae of chloroplast grana Frey-Wyssling was able to calculate their size as being equal to one to four Svedberg units, containing eight to twelve chlorophyll molecules (the molecular weight of one Swedberg unit = 17,600). Moreover, micrographs showing the exact locahzation of enzymes in the cell are now available (Sheldon, Zetterqvist, and Brandes 1955). By means of microscopical interferometric methods it is, furthermore, possible to determine mass as small as 0.01 pg//<^ (Davies, Engstrom, and Lindstrom 1953; 1 pg -- lO-^^ g). Microspectroscopical methods allow of determination of mass as small as 0.001 pg (Caspersson 1950). To be able to make use of the new developments in the field of microscopy it is often necessary to introduce new methods for preparing the material to be studied. Thus the invention of the electron microscope (Knoll and 126 Ruska 1932) called for intense research for new methods of preparation. As far as biology is concerned satisfactory results were not achieved until ultra-thin sections could be made by routine methods — almost 20 years after the invention of the electron microscope. Several new ways of prepara- tion might be convenient in ordinary light microscopy but ultra-thin sectioning will, no doubt, eventually be the most useful one. In response to a request of visitors to the Palynological Laboratory, Stockholm-Bromma, some of the problems met with when using the ultra- thin section technique will be discussed in the following. Methods oj preparation For studies of ultra-thin sections of non-acetolyzed pollen grains and spores it is, i.a., advisable to consider the question of fixation carefully. For light microscopical work fixation by means of formalin, or freezing and drying is often sufficient. Fixation with osmic acid is, however, to be preferred; in fact, in electron microscopical studies it is, so far, the only reliable fixative. Osmic acid also acts as an electron stain. In acetolyzed exines the staining effect of the osmic acid is negligible and probably of no use. Experiments ought to be made to discover, if possible, other heavy metals or ions suitable as electron stains. In investigations of mammalian tissues a buffered solution of osmium tetroxide is usually used (acetate- veronal buffer at pH 7.2; cf. Rhodin 1954). The same fixative has been used by Turian (1956) and AfzeUus (1955). In the opinion of P. Sitte (personal communication, November 1956), buffering of the solution is not partic- ularly important when fixing plant cells which have not formed a large vacuole, since the buffer might penetrate the cell more rapidly than the osmic acid and thus cause a poisoning of the cell before fixation. Sitte, moreover, emphasized the importance of using an isotonic solution of 1 per cent osmium tetroxide by adding sugar or urethan. The slow penetration of osmic acid presents a problem familiar to all who have tried this type of fixation. In pollen grains the fixative probably penetrates into the grains more readily through the aperture membranes than through the wall proper. (N.B. In order to obtain good fixations to meet the high demands of electron microscopy it might be advisable to cut large pollen grains or spores before fixing). Wettstein has obtained very good results by using osmium vapour (cf. PI. IV, V). The necessity of using suitable embedding media in the study of thin sections by means of phase contrast has recently been stressed. Ordinary histological techniques have, as a rule, been adjusted to the use of much thicker sections, for which glycerol jelly is often a good embedding medium. Thin sections (about 500-5000 A thick) should preferably be studied in 127 water, ultra-thin sections (thickness < 500 A) in air (water and air are better than glycerol jelly on account of their lower refractive index). The following formula shows the importance of a wide difference between the refractive index of the object and that of the embedding medium when the geometrical thickness of the section is decreased: OPD = e{n^- n^; OPD, optical path difference (see p. 131); /Ji, re- fractive index of the object; n.^, that of the enclosing medium; e, geometrical thickness of the object. If air is used as an enclosing medium it is, of course, possible to apply cover slips and immersion oil in the ordinary way. For theoretical reasons, however, full use cannot be made of the numerical aperture of the micro- scope. Good results have, nevertheless, been obtained by this method. When specifying the thickness of the sections, e.g. ultra-thin sections embedded in air, the figures originally obtained from electron micrographs of shadowed sections (Sjostrand, personal communication) have been used. The present author has measured the thickness of ultra-thin sections by means of interference microscopy. These measurements, in general, tend to give slightly higher values than those calculated from shadowed sections. It may perhaps not be superfluous to point to another circumstance that might cause confusion. If thin exine sections are studied by means of an ordinary light microscope a number of diffraction lines can usually be seen, due to superposed light waves in the thin exine. The number of the waves can be altered by changing the wave length of the light used (Ingelstam, personal communication). The diffraction lines must not be mistaken for lamellae or demarcation lines between different layers of the exine as has apparently been done by Pflug in describing optical sections of entire grains [cf. Pflug 1953, p. 66: "Exospore and Exinen sind aus konzentrischen Schalen (Lamellae) zusammengesetzt; das ist in unzahligen Fallen be- obachtet. Fraglich ist nur deren Zahl. Sie ist einmal subjektiv bedingt durch die Scharfe der Optik"]. Ultra-thin sections should always be properly stained in order to obtain as much information on wall stratification, cell contents etc. as possible. The fact that the immature wall of certain fungus spores is easily penetrated by stains (Nannfeldt, personal communication) seems to open up a pos- sibility for obtaining further details on sporoderm formation. Further research work in sporoderm morphogenesis is indeed necessary. In this context another problem may be mentioned: electron micrographs of acetolyzed exines often show that the exine, the endonexine excepted, is altogether homogeneous-amorphous (cf. e.g. EMG by Afzelius in Erdt- man, 1956a, Fig. 1, p. 132). No demarcation lines can be observed at a resolution of 40-50 A. Oshurkova (1956) in a review of a paper on the fine 128 structure of the pollen wall in Clivia miniata (Afzelius 1955) criticizes the use of several terms to indicate different parts of this continuous layer. If attention is paid to fine structure only this criticism seems to be justified in the case of Clivia, and many other pollen types. There are, however, exceptions. The basal part of sexinous rods in pollen grains of Cobaea penduliflora (Erdtman 1952), Ciiciirbita (Miihlethaler 1955), Linum, and some other genera (Erdtman 1956 b) is fixed well into the nexine. Studies of ultra-thin sections, suitably stained, would probably shed more light on these and similar problems, and make possible further contributions to the elucidation of the morphogenesis of the sporoderms. Electron microscopy There are practically no pollen grains or spores small enough to make possible a study of unsectioned grains or spores in the electron microscope. However, some efforts along these lines have in fact been made (cf. e.g. Burton 1946). Ueno (1949, and personal communication 1956), isolated "viscin threads" of Oenothera odorata and Gaiira lindheimeri etc., and studied them, without further preparation, by means of electron microscopy. These threads, or part of them, probably consist of the same material as the exine, since they are not dissolved if heated in an acetolysis mixture (cf. Erdtman 1952, Fig. 170B:b, p. 292, and Fig. 171 A, p. 293). Fragmentation of material, by means of ultra-sonics or other methods, was often carried out before the introduction of ultra-thin sectioning techniques (cf. the spine of a malvaceous pollen grain. Fig. 151 A, p. 262, in Erdtman 1952). It is a rapid method of preparation, but rather rough and unsatisfactory. Many fragments will be too thick and thus instantly charred by the electron beam; they defile the microscope and the method cannot be used in high resolution microscopy. Although now outmoded in electron microscopy, this technique can still be of some use in ordinary microscopical investigations. The interpretation of the micrographs is easier if the material consists of one or a few structural units only, as when dealing with acetolyzed exines. Replica methods are often useful in the study of the surface details of pollen grains and spores. Sitte (1953) has modified the wax impression method by Mahl (1942), whereas Bradley (1954, 1957), and Miihlethaler (1955) have used, with much success, a carbon replica method devised by Bradley. Bradley has thus provided new information concerning the colpi in the pollen grains of Lamium album; he has also found that the spores of Riissula verrucosa are covered with a thin amyloid film. 129 Fragmentation and replica-making can be combined with shadowing by means of metal-evaporation, although this treatment is too rough in studies of cytoplasm etc. (silver, or aluminium, is often used in light microscopy, palladium in electron microscopy). The thickness of the metal film must be calculated with care, as must also the angle at which the metal atoms are to strike the material (cf. micrographs in Wyckoff 1949, p. 110, 121, and 227-232). In high resolution electron microscopy the method has now almost lost its importance since sufficient contrast is preferably obtained by using suitable electron stains. A particularly penetrating evidence concerning the structure of the wall will, no doubt, ultimately be derived from studies of ultra-thin sections. Various types of fine structure in the resistant part of pollen and spore walls have recently been described by various authors. At a resolution of about 30 A (cf. EMG, Figure 142, page 77) acetolyzed sporoderm seems to consist of small granules, 50-60 A in diameter. They are either arranged in lamellae, with the granules in a single layer, or grouped into an amorphous type of structure. The lamellate fine structure can be transformed into the latter type of structure by means of oxydation, as has been proved in Lycopodiiim clauatum (Afzelius 1956). Hitherto, attention has mainly been centred on the fine structure of the exine. Electron microscopy may, however, also help to reveal the fine details in non-acetolyzed sporoderms and the interior of pollen grains and spores, as shown by some electron micrographs by D. von Wettstein reproduced in PI. IV and V. The following constitutes von Wettstein's description and interpretation of his E]\IG:s: The spore wall of Funaria hygrometrica is divided into three layers, intine, inner exine, and outer exine, each of which is structurally homogeneous and cannot be subdivided. The intine consists of a three-dimensional frame- work of fibrillae (probably cellulose). In properly fixed material the cyto- plasm of the spore is in close contact with the intine and obviously not separated from it by a membrane (PI. IV, Fig. c). The outermost layer of the cytoplasm seems to consist of a framework of fibrillae related in size, but not in chemical composition, to that of the intine. If, in the course of fixation, the cytoplasm is separated from the intine, some sort of mem- brane appears in the micrographs. The inner layer of the exine in Funaria displays a higher electron density than the intine. A kind of fibrillar struc- ture seems to be present although obscured by a substance between the fibrillae. The intine/exine limit is marked by a fine and dense zone about 50-100 A in thickness (PI. IV, Fig. c). In PI. IV, Fig. b, the exine seems to be separated from the intine by a special, comparatively thick, layer. Ob- viously, a corresponding layer is lacking in Figs, a and c in the same plate. These, however, exhibit radial, strictly perpendicular sections through the wall, whereas Fig. b exhibits an oblique section, as can be inferred from the 130 greater thickness of the exine as well as of the intine. Thus the effect of a special layer between exine and intine is produced by the high focal depth of the electron microscope. In reality, this layer is nothing else than an overlapping of the intine and exine, due to oblique cutting. The outer part of the exine consists of a thin layer provided with large processes. It shows a high electron density and no inner structure could be resolved so far. The processes are finely papillate and exhibit a considerable variation as to size and shape. Tangential sections through the outer part of the exine (Figs, d-e) reveal the presence of a thin superficial layer (about 150-300 A thick) covering the processes as well as the rest of the exine surface. This layer has an extremely high electron density. The inner (infrasporodermal) part of the spore consists of cytoplasm, organellae, and reserve substances. Two kinds of organellae, viz. the mitochondria and the plastids, are easy to identify: the former contain a folded structure, which is also encountered in other plants and in animals; the plastids are consider- ably larger and provided with some traces of lamellae and globular particles. They lack the typical structure found in fully grown and assimilating chloroplasts. In PI. IV, Fig. a, three chloroplasts and part of a fourth can be seen. The membranes surrounding the plastids display an interesting structure. In the last-mentioned figure there are many other small bodies with a slightly irregular surface, possibly reserve substances. They appear to consist of two components, a central grain with small electron scattering power (white in the picture), and a surrounding layer of electronoptically dense and homogeneous material. There is reason to believe that these particles constitute a polysaccharide enclosed in a fatty substance. As can be concluded from this description, a tangential section gives a more or less uneven "black" area in the pictures. Organellae and inclusions of other kinds are depicted in Figs, f-i, amongst which are a great number of droplets with a strong electron scattering power. The other three organellae in these figures differ in size and structure. They have a special type of surface membrane which is composed of a thin layer supported by dense droplets, giving, in cross-section, the impression of a pearl necklace. The chemical constitution and function of these organellae are unknown. In Paris, in 1954, Frey-Wyssling, when summing up the facts known about the submicroscopic structure of the plant cell, intimated that the fine structure of the ground plasm was influenced by the fixative used but was still largely unknown. He further intimated that the presence of micro- somes and mitochondria had been proved, but that a lamellate structure similar to that demonstrated in the large mitochondria of the kidney had not yet been found. Neither was it possible to ascertain if the nucleus was provided with a true nuclear membrane or not. The last two questions now I'l. 1\'. FuiKirid hii determination of the mass of extremely small biological objects. Biochim. biophys. Acta 4-6.' Erdtman, G. 1952. Pollen morphology and plant taxonomy. I. Angiosperms. Uppsala. • 1956 (a). Current trends in palynological research work. Grana palynologica 1: 2. 1956 (b). "LO-analysis" and "Welcker's rule", a centenary. Svensk hot. Tidskr. 50: 1. Finean, J. B., Sjostrand, F. S., and Steinm.\nn, E. 1953. Submicroscopic organization of some layered lipoprotein structures. Exp. Cell Res. 5: 2. Freytag, K. 1957. Doppelbrechende Stabchen im Olubcrzug der Pollenkorner. Svensk bot. Tidskr. (In press.) Frey-Wyssling, a. 1954. Report on the submicroscopic structure of plant cells. Huitieme Congres international de Botanique. Rapports et Communications, Section 9. Ingelstam, E. 1957. Some questions about merits of interference microscopes. Exp. Cell Res., Suppl. IV, p. 150-157. Ingelstam, E. and Johansson, L. P. 1957. Paper on aperture correction in ,7. Sci. Instr. (In press.) Johansson, L. P. 1957. An interferometer microscope for rapid measurements of optical thickness in technical and biological objects. Exp. Cell Res., Suppl. IV, p. 158-164. Johansson, L. and Afzelius, B. M. 1956. Measurements of optical path difference by means of coloured birefringent interference and a new compensation method. Nature, Lond., 178, p. 137. Knoll, M. and Ruska, A. 1932. The electron microscope. Z. Physik 78. Mahl, H. 1942. Die ilbermikroskopische Oberflachendarstellung mit dem Abdruckverfahren. Naturwiss. 30: 14, 15. MiJHLETHALER, K. 1955. Die Struktur einiger Pollenmembranen. Planta 46. OsHURKovA, M. V. 1956. [Swedish studies of sporoderms by means of electron microscopy.] Bot. J. USSR Acad. Sci. 41. (In Russian.) Pflug, H. 1953. Zur Entstehung und Entwicklung des angiospermiden Pollens in der Erd- geschichte. Palaeontographica 95. Rhodin, J. 1954. Correlation of ultrastructural organization and function in normal and experi- mentally changed proximal convoluted tubule cells of the mouse kidney. An electron microscopic study including an experimental analysis of the conditions for fixation of the renal tissue for high resolution electron microscopy. Stockholm. (Thesis.) Sheldon, H., Zetterqvist, H. and Brandes, D. 1955. Histochemical reactions for electron microscopy: acid phosphates. Exp. Celt Res. 9: 3. SiTTE, P. 1953. Untersuchungen zur submikroskopischen Morphologic der Pollen- und Sporen- membranen. Mikroskopie 8: 9/10. Sjostrand, F. S. 1953. A new microtome for ultra-thin sectioning for high resolution microscopy. Experientia 9: 3. Turian, G. and Kellenberger, E. 1956. Ultrastructure du corps paranucleaire, des mitochon- dries et de la membrane nucleaire des gametes d' Altomyces macrogynas. Exp. Cell Res. 11. Ueno, J. 1949. [On the structure of viscin threads as revealed by the electron microscope.] Kagaku 19: 7. (In Japanese.) Wettstein, D. von, 1957. Chlorophyll-Letale und der submikroskopische Formwechsel der Plastiden. Exp. Cell Res. 12: 3. WiLKiNS, M. H. F. 1953. The performance of spherical-mirror reflecting objectives when used for ultra-violet photomicrography. J. Roy. Microscop. Soc. 73: 2. Wyckoff, R. \V. 1949. Electron microscopy. Technique and applications. New York and London. MARINE BIOLOGICAL LABORATORY LIBRARY WOODS HOLE, MASS. W. H. 0. I. ON THE CUTTING OF ULTRA-THIN SECTIONS BY J. RADWAN PRAGLOWSKI Preliminary treatment oj pollen or spore material andjilling of gelatine capsules with methacrylate Before embedding in methacrylate, the pollen or spore material to be sectioned is successively washed in a centrifuge tube with distilled water (three times), 95 per cent alcohol (tw:ice), and absolute alcohol (three times). The material should remain in the last-mentioned fluid for 24 hours. The alcohol is then decanted and some methacrylate (methyl methacrylate one part, butyl methacrylate seven parts) is poured into the tube. (N. B. Liquid methacrylate contains a stabilizer which impedes polymerization and must be washed away with a two per cent NaOH solution before the meth- acrylate is poured into the tube.) The methacrylate is renewed three times at intervals of two hours and should be shaken, often and thoroughly, in order to prevent the pollen grains from sedimenting. After the last re-filling the fluid is shaken once again and transferred by means of a small suction pipe to gelatine capsules (No. 3 from Parke, Davis & Co., London; see Fig. 254). It is important to add a proper amount of pollen grains ot the methacrylate. If too many grains are added the polymerization of the methacrylate (vide postea) may be rendered more difficult. Polymerization in UV light I'he liquid methacrylate is polymerized, i.e., transferred into a solid state by exposition to UV radiation; this method is to be preferred to poly- merization induced by heat with the aid of a catalyzer, since the catalyzer may oxidize the sporopollenine. The filled gelatine capsules are covered with lids and fastened in pairs to a length of tape. About ten capsules to every tape are fastened in this way and exposed to the light produced by a 120 watt UV lamp. The distance between the lamp and the tape should be about 136 t*' SUCTION PIPE GLfiSS TUBE CON- TfllNINO- POLLEN IN LIQUID METHACRYLATE. ^ 2 GELATINE CAPSULES FILLED WITH METHA- CRYLATE. GEL ATI ME CAPSULE WITH COVERING LID C ORDINARY SIZE) -> CARDBOARD HOLD- ER IN WHICH THE GELATINE CAPSU- LES ARE PLACED READY FOR FILL/NO. Fig. 254. Outfit for filling the gelatine capsules. 15 cm. At the Palynoloi^ical Laboratory, Bromma, the gelatine capsules are usually exposed to UV radiation during five nights, approximating 15 hours per night. During the first night, before the hardening of the plastic, the heat from the UV lamp should be checked by a ventilator in order to avoid the formation of air-bubbles in the sediment at the bottom of the capsules before the methacrylate solidifies (Fig. 255). After about 80 hours of exposition to the UV lamp the plastic is, as a rule, sufficiently hard for cutting. Cutting is rendered difficult if there are air-buijbles in the methacrylate. The bubbles may be due to various causes, for instance, as already men- 137 HANGING LENGTH OF TAPE WITH C-ELATINE CAPSULES. Fig. 255. Polymerization of the methacrylate with UV light. tioned, to over-heating during the initial stages of polymerization, or to an over-concentration of pollen grains, or insufficient washings of the pollen material with methacrylate. A capsule with air-bubbles can, never- theless, be used for cutting if the pyramid (see below) is made either at the side of the bubble or just above it. The cutting, oj the pyramid After soaking in water the gelatine capsules can be easily removed from the plastic units which, when dry, are ready for cutting. A unit is fixed in a steel object-holder (made by LKB-Pnxkd^ter, Stockholm 12) in such a way that three to four millimetres of the pollen-bearing part protrude from its mouth (Fig. 256). After trimming the top of the plastic unit with a razor blade (Fig. 257), a thin foursidcd process, the pyramid, containing the pollen grains or spores for sectioning is carved from the apex. 138 A 5 o V ■> PLASTIC UNIT 5IDE VIDN OF LHB HOLOLR MADE UP OF 2 INDEPENDENT PIECES OF STEEL MOUNTED AND SCREHED TOGETHER (IMITH A nEY). y/EW FROM ABOVE OF THE LHB HOLDER IVITH MOUN- TED PLASTIC UNIT. m m. Fig. 256. LKB object-holder with plastic unit mounted (1:1). When estimating the size of the pyramid, the following three factors should be taken into account: 1. the desired thickness of the sections (the thicker the sections the larger, and especially the higher, the pyramid must be); 2. the size of the pollen grains (the size of the pyramid should be in- creased or decreased in proportion to the size of the pollen grains; if large pollen grains or spores — diameter about 80 /^ or more — are to be cut sometimes as few as 1-3 pollen grains will be sufficient, cf. Fig. 258); 3. the concentration of the pollen grains (cf. Fig. 259; if the concentration > LHB STEEL HOLDER Fig. 257. Preliminary cutting of the plastic unit. 139 ^POLLEN GRAINS OBJECT-HOLDER Fig. 258. Plastic unit with ready-made pyramid. (N.B. The pyramid is enlarged about 10 times, the rest of the figure about 3 times.) is low, the dimensions of the pyramid, with a view to increasing the number of pollen grains to be sectioned, must be larger). The total height of the pyramid should not exceed half a millimetre if sections of a thickness of about 0.25-0.50 // are to be made). These recommendations have been followed when working with the modified Spencer microtome model 821 and are not always valid for ultra-thin sectioning. The best results are obtained by working with samples rich in pollen grains and absolutely clean. Organic debris renders cutting more difficult, shreds the sectioned pollen fragments, or covers them, and decreases the value of the sections on the whole. Inorganic material (e.g. silicon or other mineral particles) will damage the microtome knife. Fig. 260 illustrates the order, directions etc., to be followed when mould- ing the pyramid, but it goes without saying that there can be many modi- PLASTIC SECTIONED POLLEN Fig. 259. Section from the basal part of the pyramid, x 100. 10-565617 G. Erdlman 140 > OBJECT-HOLDER B D INCISION No I. PLASTIC UNIT /NC. No. 2. /NC. No. 5. W- D, Fig. 260. Moulding of the pyramid. (N.B. Plastic unit 4:1, object-holder about 2:1.) — A. Incision No. 1. — B. The object-holder is turned 180° and incisions Nos. 2 and 3 are made. A part of the apex of the plastic unit will fall away with incision No. 3, after which the object-holder is turned again 180°. — C. Incision No. 4 cuts off the other part of the apex of the plastic unit. Two sides of the pyramid are now ready. The object-holder is then turned 90°. — D. Incision No. 5. Dj shows the object-holder with the plastic unit in top perspective after incision No. 5. — E. The object- 141 D^\ INC. No. 6 INC. No. 7 INC. No. 8 /« ' ■ ■ ■■ ■ '■■,'■• -. ".'-." -.*.'■•■ ■ '•••^ .■.•■. ■.:■-■:•: -^ • . • • / ■ •"•'^ ';'■••','• ^^^^ ^''^^v'- *^ -V '■'■■' >■,".- yr ^r:;^.-/:-' r :''A AfSlt %. V ■':V.:'J' •:■,■;■.'. ' "*, Y". ' ^ >^ ■■';?;\^^ .'%^i,';." . ,\iV^ •J ■ '.":*. ■-* • ' * ^**^i— -i>*^ .'?■-,'••' . ■' -' 'r '»' ^ ■'• ■* . - . • - • • 'v..-;': -:■■■■*. ■ ■.-■.'-■ , .»'. holder is then turned 180° and incisions Nos. 6 and 7 are made, after which it is again turned 180°. — F. Incision No. 8 cuts away the last part of the plastic unit, and the coarse cutting of the pyramid is now complete. — G. Side view. Gi Front view of the object-holder with ready-cut pyramid, fications according to individual ways of working. Usually, the moulding cannot be considered to be complete in eight cuts, and further fine trimming along the lines illustrated in Fig. 260 is always necessary. The height of a properly moulded pyramid is always greater than the base. The grinding oj the microtome knife American "Eversharp" razor blades are used for cutting. After removing the fat with ether the blade is mounted in a special holder (LKB-Produkter, Stockholm). The grinding is performed on a sheet of planed glass. A suitable amount of grinding powder (type B. 5125, Linde Air Products Co.) and 142 "^ THE ARM OF THE MICROTOME MOVES /ERTICALLY. THE POINT OF THE PYRAMID MUST BE PLACED EXACTLY ON THE SAME LEVEL AS THE KNIFE. TROUGH ^ t^NIFE INITIAL DISTANCE .A OBJECT HOLDER . WITH PLASTIC <— ^ UNIT Fig. 261. Adjusting of the Spencer microtome model 821 for sectioning. teepol (teepol one part and distilled water four parts) should be available. The powder is thoroughly mixed with the teepol to a homogeneous, easy- flowing mixture. Ordinarily, grinding takes about 15 minutes. The pressure on the knife should be at a minimum during the last five to eight minutes of grinding. After rinsing in running water and drying with a few drops of absolute alcohol, the knife is ready to use. It should be used immediately after grinding in order to avoid rust, contamination by dust etc. The sectioning The knife is cleansed with acetone and mounted in a curved position in a special trough (made by LKB-Produkter, Stockholm). Care must be 143 -> MICROTOME THE ARM OF THE -^ MICROTOME IS NOT IN MOTION AT THIS > MICROSCOPE SHOOT /t^C- FORH/iRD Fig. 262. Adjusting of the microtome for sectioning (continued). taken to ensure that its edge is parallel with the end of the trough. Tlie latter, together with the knife, is then fixed in the microtome. At the same time, the object-holder is tightly screwed into the mobile part of the microtome. The screw controlling the thickness of the sections is adjusted in accordance with the desired thickness. Concomitantly, a final adjustment of the pyramid in relation to the knife should be made. The general condi- tions of stability must also be observed, particularly a steady under-carriage. This process, as well as that of cutting, is followed through a binocular microscope ( x 20). 144 IN THE FRONT PERSPECTIVE THE POINT OFTHE PYRAMID /S PLACED EXACTLY AT RIGHT ANGLES TO THE ED&E OF THE HNIFE. OBJECT-NOLDER PLAST/C PYRAMID KNIFE -^ TROUGH F'is. 263. Pyramid and trough, front view. By hand, and with the motor off, the pyramid is brought to the level of the knife. In order to prevent damage to the pyramid through the vertical movement of the microtome, the trough with the knife should be placed at a safe distance. The knife is then slowly brought forward to the apex of the pyramid. Fig. 261 outlines the mobile part of the microtome, the knife-trough part (side view), and the vertical adjustment of the lever of the microtome with the mounted plastic unit. Fig. 262 shows the knife-trough block and the microscope. The final adjusting for sectioning is followed under the microscope. In the visual field will be seen the facet of the knife, the liquid (20 per cent alcohol in water) with which the trough has been filled, and the plastic unit with a part of its holder. One of the base lines of the pyramid must be parallel to the facet of the knife which should be brought as near as possible to the apex of the pyramid without coming into contact with it. The knife-trough block is then fixed, and the level of the liquid checked (the surface should be slightly convex). The motor is then started. Some introductory movements of the micro- tome carry the apex of the pyramid towards the knife. The microtome feeds at every second stroke. Normally, the sections assemble in the 145 SIDE y/£W THE PYRAMID fS ADJUSTED HORIZONTALLY CE OF QUID TROUGH AND 5TEEL PLATE IN CROSS SECTION. PLATE Fig. 264. Pyramid and part of trough, side view. trough, grouping themselves into wreaths, strips, or small flocks. If there is too much liquid they will disseminate and, furthermore, water will pos- sibly adhere to the pyramid. Inspection of the sections through the micro- scope will be rendered difficult or impossible by disturbing light refraction, resulting from an exaggerated convexity of the surface of the liquid etc. Occasionally, the sections will roll themselves up on the surface of the liquid, but they will regain their original shape if allowed to float in the trough for a few minutes before fishing up. — The above methods of embed- ding, cutting of pyramids, grinding and sectioning have been recommended by, i.a., F. S. Sjostrand, Karohnska Institutet, Stockholm. Thefishing-up oj the sections The sections are fished up from the trough with a thin, fine-pointed, soft brush, and transferred to a sUde which has been thoroughly cleansed (albumin glycerine is not used). A drop of alcohol (20 per cent) is placed on the centre of the sUde. The brush is then inserted into the liquid and slowly pushed towards that part of the knife where the sections are as- sembled. When the tip comes under the sections the brush is carefully lifted up over the surface of the water, turned upside down, and allowed to touch the surface of the liquid on the slide. At this stage a preUminary 140 COySR-GLASS I^ITH SECTIONED POLLEN FRAGMENTS EMBED- DED IN GLYCERINE- JELLY. LAVATERA PALLIDA SECT/0/^ THICHNESSO^Sm, ruCHSIN !<- /(ff/W/v,. -4 PARAFINIZED AREA UNDER A COI/ER-GLASS Fig. 265. Microscope slide with sectioned pollen walls. check under the microscope can be made in order to get an idea of the quality of the sections. Further treatment depends on the number of sections transferred to the slide. If there are only a few it is better to allow the liquid on the slide to dry in the air. If the slide contains a great number of sections it is better to wash it with one or two drops of absolute alcohol. Although this proce- dure will probably wash away a number of the sections it is, nevertheless, worth while because the alcohol will separate the sections from each other and, at the same time, remove any dust etc. on the slide. When dry, the slide is rinsed once more with absolute alcohol. After the alcohol has evaporated the plastic is dissolved in acetone. The dissolving of the plastic, staining and mounting The acetone usually dissolves the plastic in a few hours (generally, the slide is left over-night in the acetone). After inspection under the micro- scope at low magnification (about x 60) good section-bearing areas are marked with a diamond. The slide is then again carefully rinsed with absolute alcohol and with slowly running water. If the sections are not to be stained, the slide is ready for mounting. Staining with fuchsin, safranine, or methylene blue is useful, and in fact often necessary, particularly if the thickness of the sections is only 147 0.5 /i or less. The stains are dissolved in cnvettes filled with water (ap- proximately a knife's point to a cuvette). Staining is effected in about 4-5 hours. Bismarck brown, malachite green, and other stains have been tried, but with less satisfactory results. Staining greatly facilitates the localizing of the sections as unstained sections thinner then 0.3 /^ are often difficult to locate under an ordinary microscope. After staining, the slide is rinsed with water and allowed to dry. Mean- while, minute glycerine jelly cubes (about 1 mm^) are cut, and a number of cover-slips carefully cleaned. The cubes are placed on those parts of the shde which have previously been marked with the diamond. The size of the cubes should vary in relation to the size of the section-bearing areas. A cover-shp is then placed on top of each jelly cube, and the jelly slowly melted. Care should be taken to prevent the jelly from spreading to the edge of the cover-slip. The slide is then sealed with paraffin-wax. To this end a small piece of paraffin (melting point about 70 centigrades) is placed at the edge of the cover-shp. The shde is then slowly heated in order to melt the paraffin which is sucked in under the cover-slip forming a protecting zone around the section-bearing glycerine jelly (Fig. 265). When the paraffin has cooled and hardened, the shde is cleaned with a knife and cotton wool soaked in benzol. For further information see "Sjostrand Ultra-Microtome. Instructions for use". (Distributed by LKB-Produkter, Stockholm 12.) INDEX The references to illustrations are distinguished by heavy figures. Generic names are in italics. The names of species are not included. Abies 4, 6, 7 Acmopyle 7 Acroschisma 100 Acrostichum 46 Actiniopteris 46 Actinostrobus 8 Adiantopsis 46 Adiantum 47 Agathis 8 Almis 131 Alsophila 47 AmentotaxLis 8 Amphidesmium 47 Amplectator 60 Anarlhropleris 48 Andrcaeaceae 99 Anemia 78 Ancuraceae 99 Angiopteridaceae 45 Angiopteris 79 Anoectangiiim 100 Anthoceros 100 Anthocerotaceae 99 Aposaccale 3 Aposaccia 3 Araiicaria 9 Araucariaceae 5 Arceuthos 26 Archangiopteris 79 Archidiaceae 99 Archidiiim 101 Aspleniopsis 48 Asplenium 49 Athalamia 101 Attirolaxis 9 Alhgriiim 49 Austrotaxus 9 Azo//a 50 Azollaceae 45 B/asm 101 Blasiaceae 99 Blechnum 50 Blindia 103 Bolbilis 51 Botnjchium 83 Bowenia 10 Brachiolejeunia 102 Brainea 51 Bryophyta 99 Bryaceae 99, 102 Brijum 102 Buxbaumia 102 Buxbaumiaceae 99 Buxbaumiales 102 Callitris 10 Calomniaceae 99 Calomnium 103 Calymperaceae 99 Calymperes 103 Cappa 3 Cappula 3 Catascopiaceae 99 Catascopiiim 112 CVrfrus 4, 10, 11; PI. 1 (facing p. 12) Cephalotaxaceae 5 Cephalotaxus 12; PI. I (facing p. 12) Ceratodon 103 Ceratopteris 52, 53 Ceterach 53 Chamaecyparis 23, 26 Cheiropleiiria 54 Chrislensenia 79 Christenseniaceae 45 Cibotium 54 Cinclidium 102 C/eyea 104 Cleveaceae 99 C/fj;/a 128 Cnemidaria 55 Coftoea 128 Codoniaceae 99 Conocephalaceae 99 Conoccphalum 104 Corpus 3 Corpus (height, breadth, depth) 4 Corsinia 105 Corsiniaceae 99 Cristae marginales 4 Cristae proximales 4 Cryptograwma 55 Cryptomeria 12 Ciicurbila 128 Cunninghamia 12 Cupressaceae 5, 26 Cupressus 23, 24 Cyathea 56 Cyatheaceae 45 Cyathodiaceae 99 Cyalhodiiim 105 Cycadaceae 5 Cycas 13, 20 Cyclophorus 56 Cyrtomium 56 Cystodiuni 90 Cystopteris 56, 57 Dacrydium 13, 14-18 Danaea 79 Danaeaceae 45 Davallia 57 Dendroceros 106 Dennstaedtia 57 Dicksonia 58 Dicksoniaceae 45 Dicranaceae 99 Dicranales 103 Diffraction lines 127 D/oon 18 Dipliysciaceae 99 Diphyscium 102 Diplazium 58 Dipteridaceae 45 Dipteris 58 Diselma 18 Ditrichaceae 99 Drymoglossiim 59 Drynaria 59 150 Dryopieris 60 Dumortiera 106 Elaphoglussum 60 Encalypta 107 Encalyptaceae 99 Ephedra 4, 19, 20; PI. II (facing p. 20) Ephedraceae 5 Ephemeraceae 99 Equisetaceae 45 Equisetum 60 Euosmunda 84 Exormotheca 108 Exormothecaceae 99 Fegatella 104 Fissidcns 108 Fissidentaceae 99 Fitzroya 26 Fossombronia 108 Fragmentation 128 Frullania 109 Frullaniaceae 99 Fanar/a 129, 130; PI. IV, V (facing pp. 130, 131) Funariaceae 99 Gaura 128 Georgia 109 Georgiaceae 99 Geothalliis 109 Gigaspermaceae 99 Gigaspermiim 110 Ginkgo 21 Ginkgoaceae 5 Gleicheniaceae 45, 63 Glyptostrobus 21 Gnetaceae 5 Gnetiim 22 Grammitis 61 Grimaldiaceae 99 Grinimiaceae 99 Gymnogramme 61 Gymnospermae 5 Gymnospermae, mega- spores 5 Gymnospermae, pollen grains 5 Hedwigia 110 Hedwigiaceae 99, 110 Iledwigidium 110 Helicopliyllaceae 99 Helicophyllum 110 Hemionilis 61 Hemitelia 62 Hepaticae 99 Hicriopteris 63 Histiopteris 63 HoUtumiella 64 Hookeria 111 Hookeriaceae 99 Humala 64 Hylocomiaceae 99 Hylocomium 111 Hymenoglossum 96 Hymenolepis 65 Hymenophyllaceae 45, 96 Hymenophyllopsidaceae 45 Hymenophyllopsis 65, 66 Hymenophyllum 66, 96 Hy pole pis 67 Interference microscopy 131 Isoetaceae 45 Isoetes 67, 68 Isoloma 69 Isolhecium 113 Jamesonia 69 Juniperiis P'rontispiece; 24-26 Keteleeria 27 Lamiiim 128 Larix 28 Lastrea 69 Lembophyllaceae 99 Leptolepia 70 Leptopteris 84 Leptostomaceae 99 Leptostomum 111 Leskea 111 Leskeaceae 99 Leucobryaceae 99 Leucobryum 103 Libocednis 26 Lindsaea 70 Linum 128 Lophosoria 71, 72 Lorentziella 110 Lorinseria 73 Loxsoma 12» Loxsomaceae 45 Loxsomopsis 74 Lycopodiaceae 45 Lycopodium 74, 75-77, 129, 131; PI. Ill (facing p. 94) Lygodium 78 Macroglena 96 Macroglossum 79 Macrozamia 29 Marattia 79 Marattiaceae 45 Marattiales 79 Marcliantiaceae 99 Marsilea 80 Marsileaceae 45 Matoniaceae 45 Matteucia 80 Meesea 112 Meeseaceae 99, 112 Megaceros 112 Mesosaccale 3 Mesosaccia 3 Melasequoia 29 Methacrylate 135 Microcachrys 30 Microlepia 80 Micropuncta 3 Microstrobus 30 Mielichhoferia 102 Mitochondria 130 Mniaceae 99, 102 Mohria 78 Monoclea 113 Monocleaceae 99 Musci 99 Nanomitriiiin 113 Neckera 113 Neckeraceae 99 Neckerinales 113 Negripteris 81 Neocallitropsis 30 Nephrolepis 81 Nothotaxiis 31 Oedipodiaccae 99 Oedipodiiim 114 Oenothera 128 Oleandra 81 Onoclea 82 Onychinm 82 151 Ophioglossaceae 45 Ophioglossum 83 Optical path difference 127, 131 Ormolonia 84 Orthiopieris 84 Orthotricliaceae 99 Osmic acid 126 Osmiinda 84 Osnuiiulaceae 45 Osmundastrum 84 Oxymilra 114 Oxymitraceae 99 Paindella 112 Parkeriaceae 45 Pellaea 85 Pellia 115 Pelliaceae 99 Peranema 85 Phanerophlebia 85 Phanerosorus 86 Phascum 117 Phcrosphaera 3, 30 Phlebodium 86 Phyllodadiis 31 Phijlloglossiim 87 Picea 32, 33 Pilgerodendron 34 Piliilaria 87 Pilulariaceae 45 Pinaceae 5 Pinas 34-36 Plagiochasma 115 Plagiochila 116 Plagiochilaceae 99 Plagiogyria 88 Plagiogyriaceae 45 Plastids 130 Platyceriiim 88 Platyzoma 63 Pleasiuni 84 Pleuiophascaceae 99 Pleiirophascum 116 Podocarpaceae 5 Podocarpus 36, 37, 38 Po/j/ja 102 Polarization microscopy 131 Polybotrya 88 Polypodiaceae 45 Polytrichaceac 99 Polylrichiim 116 Po«za 117 Pottiaceae 99, 117 Protocyathcaceae 45 Pseudolarix 39 Pseudotsuga 40 Psilotaceae 45 Psilotiim 89 Pleridiiim 89 Ptcridophyta 45 Pteridophyta, megaspo- res 45 Pteridophyta, isospores and microspores 45 Pyrrhobryiim 117 Pyrrosia 89 Radula 118 Radulaceae 99 Replica methods 128 Rhacomilrium 118 Rhizogoniaceae 99 Riccardia 118 P///a 120 Riellaceae 99 Riissula 128 Saccale 3 Sacci 3 Saccoloma 89 Saccus (height, breadth, depth) 4 Salvinia 90 Salviniaceae 45 Saxegothaea 40 Scapania 121 Scapaniaceae 99 Schistostega 121 Schistostegaceae 99 Schizaea 78 Schizaeaceae 45, 78 Sciadopitys 41 Selaginella 90-94; PI. Ill (facing p. 94) Selaginellaceae 45 Selenodesmium 96 Sequoia 41 Sequoiadendron 41 Serpyllopsis 72 Setosisporiles 2 Southbya 121 Sphaerocarpaceae 99 Sphagnaceae 99 Sphagnum 121 Spiridens 122 Spiridentaceae 99 Splachnaceae 99 Sf)hirhruru 122 Staining 14(5 Slangeria 42 Stenochlaena 94 Sticherus 63 Stroemia 124 Stromalopteris 63 Symphyodon 122 Symphyodontaceae 99 Symphyogyna 123 Symphyogynaceae 99 Taiwania 42 Taenitis 95 Tapeinidium 95 Targionia 123 Targioniaceae 99 Taxaceae 5 Taxodiaceae 5 Taxodium 42 Taxus 42 Tayloria 122 Tenuitas 3 Thujopsis 43 Thyrsopteris 95 Timmia 124 Timmiaceae 99 Tmesipteridaceae 45 Tmesipteris 96 Tof/^a 84 Torrcya 43 Trichomanes 96 Tsu^a 3, 43, 44 f7/o/o 124 Vandcnboschid 96 Vittaria 96 VozV/a 122 Welwilscliia 4, 19 Welwilschiaceae 5 Widdringlonid 26 Woo^/s/rt 97 Xiphopteris 97 X-ray diffraction 131 ,1 llt^lJWt ^t^X->->-' Jni.MllK'XMIJ ''v^ji'L't 2:s!WiJ^tt-L 41" ' ^Hi*-|-h->f' I (♦(-••••t'lv" i;4l;i;«sir"'^ " **• "W- ****** **!' ' • J n »«»^ !• ii-i-iTi.r->M-' •.:,; i:.;i^-i-i'i-wi-irt*H i.ci»ffi'*r f3 Minnow •**!!:' ssnc '"■'■;' jiL ' ' '•omI jHfe: |tU;.TT,:-A'^ ■ ■ I't-T Ail-M-' '1 ■ . .Ml > • - • 1 t ) 1 * .t lift , .