Ex Libris Quos Anno MCMV Doncivit Accesio N / . ANNALS OF BOTANY VOL. V O^forb PRINTED AT THE CLARENDON PRESS BY HORACE HART. PRINTER TO THE UNIVERSITY Annals of Botany ! EDITED BY ISAAC BAYLEY BALFOUR, M.A., M.D., F.R.S. QUEEN’S BOTANIST IN SCOTLAND, PROFESSOR OF BOTANY IN THE UNIVERSITY AND KEEPER OF THE ROYAL BOTANIC GARDEN, EDINBURGH SYDNEY HOWARD VINES, M.A., D.Sc., F.R.S. FELLOW OF MAGDALEN COLLEGE, AND SHERARDIAN PROFESSOR OF BOTANY IN THE . UNIVERSITY OF OXFORD W. T. THISELTON-DYER, C.M.G., M.A., F.R.S. DIRECTOR OF THE ROYAL GARDENS, KEW AND WILLIAM GILSON FARLOW, M.D. PROFESSOR OF CRYPTOGAMIC BOTANY IN HARVARD UNIVERSITY, CAMBRIDGE, MASS., U.S.A. ASSISTED BY OTHER BOTANISTS VOLUME V With XXVII Plates, in part coloured, and 4 Woodcuts London HENRY FROWDE, AMEN CORNER, E.C. OXFORD: CLARENDON PRESS DEPOSITORY, n6 HIGH STREET ' ERRATA. Page 6, footnote 2, after * wiss.’ insert ‘ Bot.’ „ 35, line 6, for ‘ germ-spore ’ read ‘ germ-pore.’ „ 63, for corrections in the Revised List of the British Marine Algae see the ‘Appendix’ on p. 522. „ 122, line 21 ,for ‘Zeille’ read ‘Zeiller-.’ „ 297, Postscript, line 11, omit ‘not’ after ‘ Cucurbitaceae.’ „ „ „ „ 29, for ‘when’ read ‘where.’ CONTENTS 520.^^ *M>I 'I'jLaJtff’ No. XVII. PACE VAIZEY, J. R. (the late). — On the Morphology of the Sporophyte of Splachnum luteum. (With Plates I and II) ... i Saunders, E. R. — On the Structure and Function of the Septal glands in Kniphofia. (With Plate III) n Barclay, A. — On the Life-history of Puccinia Geranii sylvatici, Karst., var. himalensis. (With Plate IV) . . . . . 27 Farmer, J. Bretland — On Isoetes lacustris, L. (With Plates V and VI, and Woodcut 1) 37 Holmes, E. M., and Batters, E. A. L.— A Revised List of the British Marine Algae 63 No, XVIII. [AqaJ) Bower, F. O. — Is the Eusporangiate or the Leptosporangiate the more primitive type in the Ferns? (With Plate VII) . . .109 Johnson, T. — Observations on Phaeozoosporeae. (With Plate VIII) 135 Barber, C. A. — The Structure of Pachytheca. II. (With Plate IX) 145 Baker, J G. — On the Vascular Cryptogamia of the Island of St. Vincent. (With Plates X and XI) 163 Scott, D. H. — On some points in the Anatomy of Ipomoea versicolor, Meissn. ( With Plates XII and XIII) 173 Baker, J. G. — A Summary of the new Ferns which have been dis- covered or described since 1874. (With Plate XIV) . . 181 NOTES. Thiselton-Dyer, W. T. — Note on Mr. Barber’s paper on Pachytheca 223 Webber, H. J. — On the Antheridia of Lomentaria. (With Woodcuts 2 and 3) 226 Thiselton-Dyer, W. T. — Ectocarpus fenestratus .... 227 Type-specimens of Mrs. Griffiths . . 228 No. XIX. Campbell, Douglas Houghton. — Contributions to the life-history of Isoetes. (With Plates XV, XVI, and XVII) ... 231 Scott, D. H., and Brebner, George. — On Internal Phloem in the root and stem of Dicotyledons. (With Plates XVIII, XIX, and XX) 259 Baker, J. G. — A Summary of new Ferns which have been discovered or described since 1874 ( continuation ) ..... 301 VI Contents. Elliot, G. F. Scott. — On the Fertilisation of South African and Madagascar Flowering Plants. (With Plates XXI, XXII, and XXIII) . NOTES. Hemsley, W. Botting. — Prolonged Vitality of the Seeds of Sea^ Shore Plants A Burmannia in Japan Flora of the Solomon Islands . - On Rhynchosia antennulifera m\) Vines, S. H. — On the presence of a Diastatic Ferment in Green Leaves No. XX. lf\f sff} Liry- \SUL J /— ( '(1 University Press, Oxford. jiTUiaZs of BofjiJiy Vaizey del. V A I Z E Y . — ON SPLACH NUM L U T E U M . Fiof, JL Fzy.iy. ep-^f Vol.V, P7y.IL University. Press, Oxford. Jnnals of Botasiy Vol.V, Pl.Il tp.sup. Ft#. 17. Vaizev del. VAIZEY.— ON SPLACHNUM LUTEUM University Press, Oxford. On the Structure and Function of the Septal Glands in Kniphofia. BY E. R. SAUNDERS, Newnham College , Cambridge. With Plate III. AMONG the more recent additions to the literature which deals with the subject of septal glands in plants may be mentioned the papers of Grassmann 1 and Acton 2. Grassmann’s work gives an account of the general structure and distribution of septal glands, while Acton is chiefly con- cerned with the question of sugar-formation in the gland- cells. The wider subject of floral nectaries is treated of in the earlier papers of Bonnier3 and Behrens4, but none of these observers includes in his account a detailed description of the minute structure of the secretory cells. It was sug- gested to me that careful histological examination of these cells might reveal the existence of interesting relations between their structure and their manifestation of secretory activity. I therefore made a preliminary examination of the septal glands of various species of Kniphofia , Gladiolus , Narcissus , Agave , and Polygonatum , and was led to select the first of these plants as being the most suitable for investigation. The ovary is of small size in this genus, but this drawback is more than counterbalanced by the following obvious advantages : (i) the amount of nectar secreted is considerable ; a fully open 1 Flora, 1884. 2 Annals of Botany, 1888. 3 Ann. des. Sci. Nat. 1878-79. 4 Flora, 1879. [Annals of Botany, Vol. V. No. XVII. December 1890.] 12 Saunders —On the Structure and flower contains two or three drops of very sweet nectar at the base of the flower tube, and (2) the size of the secretory cells is comparatively large. After trying various hardening reagents, I found that the structure of the cells was best preserved by treatment for three or four days with a 2 per cent, solution of ammonium or potassium bichromate (as a rule the former gave the best results). The ovaries only were hardened, and in order to ensure that the solution should penetrate as rapidly as pos- sible, portions of the external cuticle were stripped off, and the extremities of the ovary itself were removed by trans- verse section, before it was placed in the hardening fluid. I examined the following species of Kniphofia ; K. nobilis , media , aloides var. max.> and uvaria , but I was unable to detect any differences in the histological appearances which I could regard as specific ; the following account therefore applies equally to them all. I propose to describe I. The position and course of the glands, and II. The minute structure of the cells which compose the gland. I. Position and Course of Glands. The glands are normally three in number, one occurring in each septum of the trilocular ovary ; they are simple and extend almost throughout the whole length of the septum (Fig. 2). Each arises at a level only slightly above that at which the ovary-cavities make their appearance, and here forms a compact group of coherent cells, which however split apart almost immediately, and surround a central cavity, — the lumen of the gland. The lumen opens on to the external surface immediately below the base of the style (Fig. 2), and here the gland-cells which bound the lumen become con- tinuous with the epidermal cells of the external wall of the ovary. The short passage (leading on to the surface) in which this transition takes place may be conveniently termed the neck of the gland (Fig. 2, n.). In transverse section the glandular area has -roughly the form of an ellipse, the long Function of the Septal Glands in Kniphofia. 1 3 diameter of which coincides with that of the septum. This area is fairly constant at all levels except that of the neck and of the extreme base of the gland, where it diminishes, gradually in the latter case, rather more rapidly in the former. The lumen is wider in the upper and lower extremities of the gland than in the middle (Fig. 3), where the cells on either side approximate, especially at the inner margin of the gland. II. The Minute Structure of the Cells which COMPOSE THE GLAND. The gland-tissue consists of — (1) A single layer of epidermal cells ; (2) A variable number of layers (generally four or five) of modified parenchymatous cells, which lie behind the epidermal cells, and to which I shall henceforth refer as the sub-epidermal cells. Behind the sub-epidermal cells lie the ordinary unmodified parenchymatous cells of the septum, and the fibro-vascular tissue. There are from eight to twelve small fibro-vascular bundles in each lateral half of the septum ; these bundles arise at fairly regular intervals, and are offshoots from the fibro-vascular tissue running vertically in the central axis of the ovary. They bend outwards at a more or less acute angle, and, running nearly horizontally outwards in the septum, finally curve round into the wall of the ovary and there resume their vertical course (Fig. 1 ,/. v .). Since these bundles sometimes run in the unmodified parenchymatous tissue of the septum, and sometimes between it and the glandular tissue, they do not form such a well-marked line of separation between the two, as is the case, e. g. in some (?) species of Gladiolus , in which plants moreover their course in the septum is vertical. To return to the minute structure of the gland-cells.— I shall begin by describing the histological appearances which are exhibited by a typical [a) epidermal, and ( b ) sub-epider- mal cell when quite young, such cells for example as are to I4 Saunders.— On the Structure and be seen in a very young flower-bud, and shall then trace the changes which take place in (a) cell-wall, (/3) nucleus, (y) cell- contents, during the period of development from the young bud to the fully open flower, noting finally the extent to which these changes are dependent on the relative position of the cells. A. Very young Bud (Fig. 4). (a) The epidermal cells are cubical to columnar in shape, and somewhat smaller than either the sub-epidermal cells, or the unmodified parenchymatous cells of the septum. (a) The external wall (bounding the lumen) is un- cuticularised, and at first exhibits a plane surface ; the lateral and basal walls are continuously applied to those of the neighbouring cells. (/3) The nucleus occupies a very large proportion of the cell-cavity, it is generally spherical or oval in shape, and lies centrally; one, two, or three nucleoli are often present. (y) The protoplasm occupying the rest of the cell is dense and granular, and in that part of it which im- mediately surrounds the nucleus minute starch-grains very soon make their appearance. (b) The histological modifications of the sub-epidermal cells are always most marked in those lying immediately beneath the epidermis, and gradually become less and less so in those lying further from the lumen, so that there is no sharply defined boundary between these deeper layers and the unmodified parenchymatous cells of the septum, but a gradual transition from the one to the other. (a) The sub-epidermal cells vary considerably in shape, but as a rule all three diameters are roughly equal. Their arrangement is less regular and compact than that of the epidermal cells, and this character becomes gradually more marked in the deeper layers, where inter- Function of the Septal Glands in Kniphofia . 1 5 cellular spaces occur, and where the cells are generally slightly larger than those which are immediately hypo- dermal. (fi) The nuclei resemble those of the epidermis, but are smaller in proportion to the size of the cells. (y) The protoplasm is less dense, and the starch-grains more numerous than in the epidermal cells. Starch is present in the unmodified parenchyma of the septum, and occurs also in abundance in the central axis, where the grains are much larger. B. An older Bud (Fig. 5). (a) The epidermal cells are about the same size as the sub-epidermal cells, or only very slightly smaller. (a) The external wall is slightly convex, and has under- gone an increase in thickness ; in the largest buds it is seen to be differentiated into two layers, a very narrow external one which is sharply defined, and a broad in- ternal one, the inner outline of which is much less distinct than it was before the thickening took place ; in fact it has the appearance of having undergone corrosion. This thickening of the cell-wall is probably due to mucila- ginous degeneration of the inner layers, for the broad internal band no longer gives the reactions of cellulose, whereas the narrow ’ external band still appears to be coloured a pale violet by Schultze’s solution, though of this I could not be quite sure owing to its extreme thin- ness. This change never seems to involve the whole wall, since in older flowers, where the degeneration has reached its maximum, this thin membrane of unaltered cellulose can still be distinguished. (/3) The form and position of the nucleus are not appreciably altered. (y) The protoplasm is not so dense as in the cells of the younger bud, vacuoles being often apparent ; in still older buds however this vacuolation becomes less marked 1 6 Saunders . — On the Structure and owing to an increased formation of granular substance in the cells — probably a deposition of granules of meta- plasm in the cell-protoplasm. The starch-grains are larger as well as more numerous, and their outline is more distinct ; they are frequently arranged in a more or less complete ring round the nucleus, though a few are sometimes scattered in the more remote parts of the cell. ( b ) The depth of the sub-epidermal cells is generally greater than their width, i.e. they are elongated in a direction perpendicular to the lumen. (a) The nucleus is central or parietal, in the latter case it is frequently more or less flattened. (f3) The changes in the cell-contents are similar to those which occur in the epidermis ; at first during the rapid growth of the cells distinct vacuoles are formed, later there is a slight increase in the granular cell-con- tents. The vacuolation however is generally carried to a greater extent, and the deposition of the metaplasmic granules is less marked than in the epidermal cells. Starch is very abundant, large grains occurring in all parts of the cell. Both here and in older flowers most of the large grains of starch which appear to be simple are in reality compound ; by treatment with potash and iodine they can be shown to consist of several small grains held together by the ground substance of the plastid, which only becomes obvious after it is swollen by some reagent. C. Flower-tube open, anthers still closed (Fig. 6). (a) The epidermal cells show much the same characters as in the older buds, but in a more pronounced form. (a) The mucilaginous swelling of the external wall, which has now become distinctly convex, is greater, and the corroded appearance of the internal surface more marked ; in most cells the upper part of the lateral walls is also involved in the former change ; the narrow ex- ternal layer is obvious here and in all later stages. Function of the Septal Glands in Kniphofia. 1 7 ( j3 ) At first starch-grains are still very abundant, but later they become disorganised, and begin to disappear ; this disorganisation is especially apparent in the more external part of the cells. In the majority of the cells there is a considerable increase in the amount of granular substance ; in a few here and there the protoplasm is arranged in the form of a coarse mesh work \ as a result of vacuolation. (b) In the sub-epidermal layers there is even less alteration in the appearance of the cells ; the starch-grains are beginning to break down, and the granular substance has increased in amount ; here too, as in the epidermal cells, the formation of a protoplasmic meshwork and vacuoles is occasionally seen. D. Flower-tube open, some or all of the anthers having dehisced (Fig. 7). (a) In this stage there is a marked alteration in the appear- ance of the cells. (a) The characters of the external wall are similar to those described in the preceding stage, but are slightly exaggerated ; about this time the mucilaginous degenera- tion reaches its height. (j8) Very little starch is to be found in the cells, in fact so rapid has its disappearance been, that in those flowers in which all the anthers have dehisced, most of the cells are entirely free from it. The protoplasmic meshwork, which in the previous stage is not unfrequently to be found here and there occupying a small part of an isolated cell, is now almost universal ; it extends from the denser perinuclear protoplasm to that which lines the cell- wall, and is generally closer towards the lumen than at the base of the cell. The meshes are spherical or polygonal, 1 I have intentionally used the term meshwork in preference to network , since I am inclined to believe that this structure ought not to be regarded as a true network. C 1 8 Saunders. — On the Structure and and they vary considerably in size ; owing to this irregu- larity, and to the position of the nucleus (generally central), it is difficult to determine the average number of meshes in a cell. In those cases where the meshes are large and few in number (Fig. 9), the cells in all proba- bility represent a slightly more advanced stage of activity, and one through which those containing a large number of smaller vacuoles will have to pass before reaching the next and final stage ; for it is not at all uncommon, as I shall have occasion to point out later, for the cells at the same level to exhibit different stages of activity. ( b ) In the sub-epidermal cells (Fig. 8) the appearance is even more striking, for since the position of the nucleus is most frequently parietal, the meshwork stretches un- interruptedly throughout the cell. Such at least is generally the case when the dehiscence of the anthers is complete ; during the period of dehiscence the regu- larity of the meshwork is somewhat broken by the starch, which is still fairly abundant, and the disap- pearance of which takes place later here than in the epidermal cells ; so much so indeed, that some may still be found in almost every sub-epidermal cell, when the epidermis contains none. The breaking down of the starch begins in the superficial cells, and extends gradually to those lying deeper. The average number of meshes in the long diameter of the cell is about twelve. A good deal of the starch has disappeared from the un- modified parenchyma of the septum, but there is still a con- siderable amount in the cells of the central axis. E. Pollen mostly shed, and perianth often beginning to wither (Fig. 10). (a) (a) The external wall presents the same appearance as in the previous stage. (8) The nucleus, which may be much flattened, is generally parietal. 19 Function of the Septal Glands in Kniphofia. (y) The cell-cavity is occupied by a large central vacuole, the mesh work having entirely disappeared. In some of the cells the protoplasm has a highly refractive and homogeneous appearance ; in others it is granular as in the preceding stages. Sometimes the nucleus pro- jects into the vacuole, and the perinuclear protoplasm is connected with that lining the cell-wall by one or more strands ; occasionally it may lie right across the cell. (Fig. 10 b.) ( b ) The disappearance of the meshwork is not confined to the epidermis, it occurs also in the sub-epidermal cells, though not synchronously ; but just as was the case with the starch in the preceding stage, so here, the change occurs later, lasts longer, and proceeds gradu- ally from the more superficial to the deeper layers ; even after the perianth has begun to wither the mesh- work is still present in many of the cells. All the starch has disappeared from the unmodified cells of the septum, but it is still to be found in the central axis. Such is a brief account of the structural changes, exhibited by the gland-cells, during the development of the young bud into the fully open flower. There are, however, other slight variations in histological appearance, which appear to depend, not on the age of the cells, but on their position in the gland. Thus those epidermal cells which bound the peripheral margin of the lumen (Fig. % p.mi) are smaller than the other epidermal cells of the same level, and the changes which they display are less marked, e. g. the degeneration of the external wall and the deposition of starch are inconsiderable, and the meshwork is never prominent. On the other hand, those cells which bound the central margin of the lumen (Fig. i c.m.) are generally larger than the remaining cells of the same level ; the deposition of starch is greater, and its disappearance slower, here than elsewhere ; hence in flowers which are either opening or fully open, these cells exhibit a less advanced stage of activity than the others at that level. C 2 20 Saunders . — On the Structure and Corresponding local modifications are much less marked when the gland is examined vertically. In the neck, how- ever, there is a somewhat sudden alteration in the structural features of the epidermal cells ; they lose their special secretory characters, and do not differ from ordinary epidermal cells. The external wall does not undergo mucilaginous degenera- tion, and possesses a distinct cuticle, which at the mouth of the gland is continuous with that of the ovary-wall. There is no deposition of starch, and no characteristic meshwork ; the nucleus is generally central, and except in quite young cells the protoplasm is scanty, and contains a few large vacuoles. Probably all, or nearly all, the cells of a gland pass through the whole series of changes above described, yet these changes do not always occur simultaneously in the cells. This is shown by the fact that in any section of a gland the cells are not all found in the same stage of activity, a condition of things particularly obvious in flowers in which the gland-cells have been fairly active, and in which the slight differences present in the earlier stages have had time to accumulate. Thus a section, in which the majority of the epidermal gland- cells are passing through the meshwork stage, is sure to con- tain some which have already reached the final stage, with parietal nucleus, large central vacuole, and no meshwork ; while in others starch may be present, and the meshwork not yet apparent. In consequence of this unequal manifestation of activity, no one particular stage of the secreting cells can be said to be coincident with, and entirely confined to, one particular stage in the development of the flower. At the same time that appearance which is most common among the gland-cells at any one stage of the flower may be regarded as £ typical ’ of that stage, it being always understood that cells exhibiting those stages which precede and follow the typical one may be, and generally are, present as well. The following table indicates those characters of the gland- cells which are typical of the various stages in the develop- ment of the flower : — 2 I Function of the Septal Glands in Kniphofia . Stage in the develop- ment of the flower. A. Young Bud. B. Older Bud. C. Flower open, anthers closed. D. Some or all the anthers open. E. Flower be- ginning to wither. TYPICAL APPEARANCE OF— Epidermal cells. Sub-epidermal cells. External wall exhibits plane sur- face— no mucilaginous degenera- tion. Nucleus central in position. Starch-grains few and small. External wall slightly convex- mucilaginous degeneration be- ginning. Nucleus central. Protoplasm at first vacuolated, later becomingmoregranular. Starch- grains larger and more nu- merous. External wall convex, — mucila- ginous degeneration considerable. Nucleus central. Starch abundant at first, disap- pearing gradually later. Cell-contents very granular. Mesh- work rare. External wall as in C. — mucila- ginous degeneration about at its maximum. Nucleus central. Meshwork almost universal. Starch generally wanting. External wall as in D. Nucleus parietal. Meshwork disappeared — replaced by large central vacuole. Starch wanting. Nucleus and cell-contents as in epidermal cells. Nucleus central or parie- tal. Cell-contents as in epi- dermal cells. Nucleus generally pa- rietal. Starch as in epidermal cells. Cell-contents rather more granular than in B. Nucleus generally pa- rietal. Meshwork fairly general. Starch-grains few. Nucleus parietal. Meshwork still general. Starch generally wanting. As the flower withers still more the meshwork disappears as in the epi- dermal cells. It now remains to consider the significance of these struc- tural changes, and their relation to the process of secretion. Already in the bud there is indication of considerable activity on the part of the gland-cells, for there occurs in them a continued formation and accumulation of starch (forming a 22 Saunders. — On the Structure and temporary reserve material), and also of granular proteid substance (metaplasm). Further, in the epidermal cells these processes are accompanied by a change in the character of the external wall, a change which continues until it reaches a maximum in the fully open flower ; the internal part swells, becomes mucilaginous, and loses its clear inner outline, the appearance of the internal surface being such as to suggest an active destructive influence on the part of the protoplasm. As the secretion must pass through both layers of the ex- ternal wall before reaching the lumen, it is possible that some of the mucilage contained in it may be derived from the inner layers of the wall, and may have been carried along by the flow of the secretion. When the flower-tube opens the starch begins to diminish, the large apparently single grains break up into the separate grains which compose them, and these rapidly disappear. The question at once arises, are these starch-grains converted into some form of soluble carbohydrate which is then excreted ? Has their disappearance from the cells any direct connection with the presence of sugar in the secretion ? Before attempting an answer to these questions, it was necessary to determine at what stage in the develop- ment of the flower the sugar first made its appearance. With this object in view I treated sections from flowers of different ages with Fehling’s solution, but with extremely unsatisfactory results ; the reduction was always most diffuse, and was evidently caused by substances other than sugar. Abandon- ing this method as useless in this particular case, I was obliged to fall back upon the extremely rough plan of tasting ; no sweet taste could be detected, nor was there any liquid visible in the flower-tubes of buds, nor in those flowers in which the perianth had just opened ; but in those in which the stamens were projecting from the open flower-tube, though the anthers were still closed, it was possible to detect a sweet taste1. Now the histological appearances which are charac- 1 In thus testing for sugar, I used almost exclusively flowers of K. media ; in K. nobilis , owing to the greater length of the flower- tube, the stamens do not project through the open tube while the anthers are still closed ; consequently the Function of the Septal Glands -in Kniphofia . 23 terlstic of this stage in the development of the flower are those which have been described as occurring towards the end of stage C. It would therefore appear that by the time that the disintegration of the starch is well-advanced, and has become general in the gland-cells, an appreciable amount of nectar has been secreted. How much earlier than this the sugar makes its appearance I am unable to state, but it seems not improbable that some is formed simultaneously with the first indication of a breaking down of the starch, but that the amount is too small to be detected by the above-mentioned method, and that the disappearance of the one is directly connected with the appearance of the other. This change is doubtless effected by the protoplasm, and is presumably due to some ferment-action. As the starch disappears from the cells the protoplasm again becomes vacuolated, and assumes a most characteristic arrangement, viz., that of a coarse meshwork which gradually extends throughout the whole cell. As secretion continues the protoplasm gradually decreases in amount, and seems to be used up in the process ; the strands become fewer, and the vacuoles, owing to the consequent fusion, larger. This con- tinues until the strands have all disappeared, the fusion is complete, and the cells contain a single large vacuole. As the strands disappear the nuclei of the epidermal cells, either pushed by the enlarging vacuoles, or carried with the retreating protoplasm, are gradually withdrawn from their position in the centre of the cell into the protoplasm lining the cell-wall ; in the sub-epidermal cells this migration of the nucleus takes place earlier. In this last stage then, when the period of secretion has come to a close, the appearance of both kinds of cells is similar to that of ordinary adult parenchymatous cells. recognition by any external mark of a stage intermediate between that at which the perianth is just opening and that at which the anthers have begun to dehisce is very difficult. Since however the histological changes run the same course in the gland-cells of both species, it seemed to me not unjustifiable to assume that the appearance of the nectar is probably coincident with the same typical stage in both cases. 24 Saunders.— On the Structure and The changes which here accompany secretion seem slight when compared with those generally met with in the gland- cells of animals ; it must, however, be borne in mind that here the act of secretion occurs only once ; it begins, lasts for a longer or shorter time, and ceases as the flowers pass maturity, but does not recur. Consequently there is no repetition of the cycle of changes, nor is there any indication of the active constructive metabolism, of the regeneration of the protoplasm, which must necessarily take place in cases where the cells exert their secretory power again and again. Moreover, it almost necessarily follows from the comparatively long period of time over which the one act of secretion extends, that the changes which do occur should be very gradual. There is one other point which may be mentioned in connection with the histological appearance of the glands. After the ovaries have lain for several weeks in alcohol, bodies sometimes spherical, sometimes more or less irregular, and often exhibiting a double outline, make their appearance ; they are most abundant in the gland-cells, and especially in the later stages. They appear to resist the action of both acids and alkalies ; with regard to staining reagents they behave like and are probably identical with the ‘ amyloid- blaschen’ mentioned by Behrens 1 ; these latter were regarded by him as being probably some form of carbohydrate origin- ally in solution, but which separated out owing to the pro- longed action of the alcohol. 1 Flora, 1 8 79, p. 85. Function of the Septal Glands in Kniphofia. 2 5 EXPLANATION OF FIGURES IN PLATE III. Illustrating Miss E. R. Saunders’ paper on the structure and function of the septal glands in Kniphofia. All the figures were drawn with obj. F. oc. 2 (Zeiss) except figs, i, 2, 3, and 11. Fig. 1. (diagrammatic). Part of a transverse section of an ovary showing one septum, and the position of the gland-lumen. 1. lumen : f. v. fibro-vascular bundles : e. external wall of the ovary : 0. loculi of the ovary. Fig. 2. (diagrammatic). Septum in optical longitudinal section. To show the position and extent of a gland, the area of which is shaded, n. neck : p. m. peripheral margin : c. m. central margin : st. style. Fig. 3. (diagrammatic). Septum in longitudinal vertical section. 0. e. 1. as in fig. 1. (The ovules have been omitted from the drawing). The following lettering applies to all the succeeding figures, n. nucleus : vacuole : s. starch-grains : a. thin outer layer of external wall : /?. broad inner layer : S. metaplasm : m. mesh-work. Fig. 4. Epidermal gland-cells from a young bud. Fig. 5. Epidermal cells from an older bud with numerous large starch-grains, granular contents, and in some cases vacuoles. External wall shows slight thickening. Fig. 6. Epidermal gland-cells from an open flower in which the anthers are still closed. The mucilaginous degeneration is now well-marked, the thin cellulose membrane is indicated by the thick dark line (a), the mucilaginous layer by the broad band (/3). The cells contain very many large compound starch-grains, and much granular metaplasm. Fig. 7. Three epidermal cells from a fully open flower. To show the meshwork stage. Starch absent. Fig. 8. To show the same stage in sub-epidermal cells. In all but d. the nucleus has been omitted, and in c. and d. the meshwork has been ruptured in the preparation. Fig. 9. An older stage than fig. 7. The meshwork is beginning to disappear, and the nucleus is being withdrawn from its central position. Fig. 10. Epidermal gland-cells in the last stage. The meshwork has disap- peared, and been replaced by large vacuoles, and in a and c the nucleus is parietal. Fig. 11. Obj. cc, oc. 2. (Zeiss). Transverse section of part of a septum. To show the relation of the glandular area {gl) to the unmodified tissue of the septum (u.t.). Vol. V, PL. III. University Press, Oxford. t-Annals of Botany 6 Saunders del. SAUNDERS. — S E PTA L G Vol. Vf PI. Iff. NDS OF KNIPHOFIA. University Press, Oxford. /truiaZs of Botany Vol. V, PL. III. SAUNDERS. - SEPTAL GLANDS OF KNIPHOFIA. University Press, Oxford. Saunders del. On the Life ■ history of Puccinia Geranii silvatici, Karst., var. himalensis. BY A. BARCLAY, M.B., Bengal Medical Service . With Plate IV. IN this paper I propose to describe the life-history of a Puccinia on Geranium Nepalense , Sweet, which is in- teresting in several respects. In the first place it is complete without any other form of spore-formation than the teleuto- spore : in the second place there are two distinct crops of these spores during the spring and summer : and in the third place it is both a Leptopuccinia and a Micropuccinia. I am of course aware that the first point, viz. the absence of any other spore-form in an otherwise complete species, is not unique; but experimentally proved instances of such cases are few enough to render any additional example interesting. Thus for example P. Arenariae , Schum. ( P . Dianthi , D. C.), a so-called Leptopuccinia, is, I believe, com- plete without any other spore- form ; and so also is P. Adoxae , D. C., a Micropuccinia. Plowright 1 writes of the latter : — ‘ Mr. Soppitt placed some over-wintered teleutospores in active germination on healthy plants, in March, 1888; in ten days the teleutospores had reproduced themselves without the intervention of either uredospores or aecidiospores.’ Lastly, Chrysomyxa Abietis , Wallr. is another example of the same kind. I have had this fungus under observation in nature for 1 ‘ British Uredineae and Ustilagineae,’ p. 208. [Annals of Botany, Vol. V. No. XVII. December 1890.] 28 Barclay —On the Life-history of several years, and during the last two years under special observation in my laboratory. In a Descriptive List of the Simla Uredineae 1 I referred the species provisionally to Puccinia Geranii silvatici , Karst., and, indeed, its general habit and morphological characters approach those of that species closely ; but a more minute and careful study of it convinces me that it is at any rate a very marked variety. The host is in full vegetative activity in March, and on the 24th of that month (1889) I found numerous plants largely attacked in two localities especially though also elsewhere ; and very frequently a small area bearing many plants had every plant attacked, so that it was difficult to find one free. This led me to suspect that the spores were self- attacking, i. e. that the fungus was autoecious. Shortly -after this the host having flowered died out more or less completely, and the fungus was for a time entirely missed. But towards the end of June a new crop of the host springs up, on the setting in of the monsoon rains. I was surprised to find that in these two localities in which the fungus was very abundant in March and April, this new crop of Geranium plants was again as extensively attacked. The fungus thereafter continues to be met with until August, when it disappears for the year, not to reappear until the following spring. The whole cycle of development is then repeated. In each crop I looked carefully for the other usual spore-forms, and especially for uredospores and spermogonia ; but I could find no trace of either, and convinced myself that no other spore-form is developed by the fungus. (Expt. 1.) — On the 24th March I placed some spores of the first crop in water in a watch-glass, and also in a hanging drop of water in a closed cell. No germination ensued in the hanging drop ; but on the 28th (24 x 4 hours) I found that numerous spores in the watch-glass had thrown out promy- celia bearing sporidia. The promycelia were mostly aerial, and the spores which had become submerged did not 1 Journal of the Asiatic Society of Bengal, vol. Iviii. Pt. ii. No. 2, 1889. Puccinia Geranii silvatici , Karst. 29 germinate. Up to the 28th only a spore here and there germinated ; but on that date germination was general. Hence the spores are slow in commencing to germinate. (Expt. 2.) — Similarly I floated freshly gathered spores of the second crop on water in a watch-glass on the 13th June, and on the 15th (24 x 2 hours) noted that some, though not many, had germinated, and had produced sporidia. (Expt. 3). — As a comparative experiment I also placed some spores of the first crop, which I had collected on the 23rd March, in another watch-glass under exactly similar conditions. These germinated very freely, producing many more sporidia than the fresh spores of the second crop. (Expts. 4, 5.) — I transferred the sporidia from each watch- glass (Expts. 2 and 3) to two halves of a healthy plant bearing young leaves, which I had uprooted carefully on the 15th June, and had placed in a glass vessel with the roots in water. The plant was then kept in my laboratory under a glass shade. On the 25th the part inoculated with the sporidia of the first crop showed two distinct points of attack on one leaf, while the other part remained free from visible attack. On the 28th the former inoculated part showed other two small crops of pustules on the stems. The part inoculated with freshly gathered spores of the second crop remained free from any sign of attack so long that on the 1 2th July I removed it from under the shade, and left it naked on a shelf in my laboratory, and did not look at it again until the 22nd, when to my surprise I found one leaf typically crumpled, with numerous black teleutospore-pustules. (Expt. 6.) — The spores taken from the last were placed in water in a watch-glass on the 22nd July; but they refused to germinate, and I had evidently come to the end of the series of teleutospore-generations, and had reached those destined to lie dormant until the following spring. I pre- served some of these spores for use next spring; but un- fortunately they became mouldy, and were presumably killed, as they did not germinate in March. This unfortunate mis- hap has prevented my completing experimentally the whole 30 Barclay . — On the Life-history of life-cycle of the parasite from one year to another. But there can be no reasonable doubt that the teleutospores formed at the end of summer lie dormant until the following spring. These promising results induced me to continue my ob- servations in the following year. (Expt. 7.) — On the 2nd April, 1890, I collected some fresh spores and put them into water : on the following day there was no sign of germina- tion : from the 4th to the 7th I was absent from my labora- tory ; but on the 8th (24 X 6 hours), on my return, I found that they had germinated very freely, the water containing numerous sporidia. (Expt. 8.) — Again, on the nth I collected fresh spores and put them into water on the 12th. On the 13th and 14th there was no germination : on the 15th (24 x 3 hours) some had germinated, and there were some sporidia in the water; but it was not until the 19th (24x7 hours) that germination had become free, and the water held immense numbers of sporidia. (Expt. 9.) — Lastly, on the 19th April I collected more fresh spores and put them into water: on the 20th there was no germination : on the 21st a good many had germinated : on the 22nd (24 x 3 hours) germination was general. At the same time I undertook some inoculation experi- ments, and will give the details of two, which establish the life-history of the fungus. (Expt. 10.)— I inoculated a potted plant, which I had in confinement since the preceding autumn, several times with sporidia during April. On the 23rd I noticed two distinct points of attack on one leaf, though as yet there was no spore-eruption. This, however, occurred on the 29th, when I saw two or three black pustules on each spot of attack. On the 9th May I noticed that another leaf was wholly attacked, including the whole of the petiole. (Expt. 11.) — On this date I removed some spores and placed them in water under a glass shade. On the following day some had germinated and had produced sporidia (Fig. 3) ; but on the 13th (24x4 hours) germination was free and complete. Puccinia Geranii silvatici, Karst . 31 (Expt. 12.)— Having uprooted a healthy plant, and having placed its roots in a glass vessel containing water, I inoculated it freely on the 25th April with sporidia from a cultivation started on the 23rd, and kept it in my laboratory under a glass shade. On the 4th May (nine days) I noticed several foci of attack on three leaves ; but there was as yet no spore eruption. On the 9th May (fourteen days) the plant was very extensively attacked in leaves, petioles, and stems, with marked hypertrophy of the latter, and large spore-eruption (Fig. 1). (Expt. 13.) — On this date I removed some spores and placed them in water as a parallel cultivation with that described above (1). On the 10th none had germinated, but on the 13th (24x4 hours) germination was free, though not quite so general as in the parallel cultivation. This was probably due to many of the spores being much younger and more immature. These experiments prove that the spores of the first (Expts. 1, 3, 7, 8, 9, 11, 13) and second (Expts. 2 and 6) crop are both Micropuccinia and Leptopuccinia ; and that the fungus is complete and autoecious with teleutospore-formation only (Expts. 4, 5, 10, and 12). I venture to think that the estab- lishment of the former point, namely the power the spores of each crop possess of both germinating at once and after rest, more or less prolonged, is important, since it shows that Schroter’ s divisions Lepto- and Micro-puccinia, though they may prove useful artificial classes in those cases in which the life-histories are unknown, are not based on fundamental biological facts as he supposed. Schroter writes1 that the mycelia produced by sporidia derived from teleutospores which have passed through a period of rest bear spermogonia and aecidia, while those produced by sporidia derived from teleutospores which have germinated at once bear only teleu- tospores again. With reference to the former proposition we have here an experimental demonstration that the sporidia of even over-wintered teleutospores can reproduce teleutospores ; 1 Die Pilze Schlesiens, page 297. 32 Barclay —On the Life-history of and with regard to the latter statement we have an experi- mentally proved case to the contrary in Puccinia Polliniae (Heteropuccinia), the life-history of which I have described else- where1, and where it was shown that the teleutospores germi- nated both at once. and after a period of winter rest, in each case producing a mycelium bearing aecidiospores. I advanced the view then that in the case of P. Polliniae the immediate germination of the teleutospores helped to distribute the fungus, vicariously taking up the function of uredo- and aecidio-spores, the former of which are not abundant in this species. I also developed this view in a paper recently submitted to the Linnean Society on the life-history of the remarkable Uromyces Cunninghamianus. In the present case, and in all similar cases, where no separate spores are produced for distributive purposes (uredo- and aecidio-spores) the teleu- tospores must perform both distributive and preservative functions (unless there is a perennial mycelium, which there is not in the case under consideration) ; and in order to accom- plish the former the spores must be capable of germination immediately, and to accomplish the latter must also be able to rest. In similar cases, where only teleutospores are produced, if there be a perennial mycelium to ensure the persistence of the species, it is conceivable that the teleutospores would subserve only a distributive function, being all immediately capable of germination. Puccinia Adoxae , Schum. would however be in evidence against this view, if it really has a perennial mycelium, and if the spores are really only capable of germination after a winter rest. It is quite possible however that an immediate power of germination after ripening has been overlooked in this species. But curiously enough it is exceptional to read of a so-called Leptopuccinia having a perennial mycelium, and if all those so classified are really complete fungi, which I think is extremely doubtful, their teleutospores will probably be found on careful examination to germinate both immediately after ripening and after a winter rest. 1 On the Life-history of a new Aecidium on Strobilanthes Dalhousianus , Clarke, Sc. Memoirs by Medical Officers of the Army of India, Part II, 1887. Puccinia Geranii silvatici , Karst . 33 This I find is the case with P. Urticae which, also, has not a perennial mycelium l. I have not yet succeeded in tracing its life-history; but it is certainly not connected with Aecidium Urticae , Schum., as I have elsewhere shown. It possibly runs a parallel course with P. Geranii silvatici ; but it is more probably a heteroecious species. However this may be, I have frequently found the teleutospores which are produced in autumn (there are no uredospores) germinate freely at that time ; and I have recently found that they germinate equally after a winter rest. I gathered some leaves bearing tele- utospore-pustules in November, and upon floating them on water found them freely germinating when scraped off the living leaf. Again, on the 19th April following (5 months later), and lastly on the 5th July (8 months), spores from the same collection germinated very freely. This therefore is another excellent illustration of a teleutospore being both a Leptopuccinia and a Micropuccinia. Before leaving this part of my subject I would draw atten- tion to the somewhat tardy setting in of germination in the spores even under favourable circumstances. It will have been observed that general germination did not set in until the spores had been in water about three to four days, indicating the essentially halting nature of teleutospores. My usual experience has been that if teleutospores are going to germinate at all they do so within twenty-four hours, under the conditions in which I placed the Geranium-fungus spores. This halting germination occurred in all my cultures, and appears to be characteristic. Again, it is probable that the teleutospores of the first crop, when they exercise their resting properties, can do so only for a month or so, while those of the second crop must do so for several months. I have unfortunately not been able to demonstrate this by actual experiment. There can however be little doubt on this point. The existence of the fungus in a plant is indicated both by the formation of brown spore-pustules on leaves, petioles, and 1 Journal of Asiatic Society of Bengal, loc. cit., and Scientific Memoirs by Medical Officers of the Army of India, Part II, 1887, p. 38. D 34 Barclay.— On the Life-history of stems, and sometimes by considerable hypertrophy of the two latter. Invaded leaf-blades are often considerably crumpled when extensively attacked : oftener only a portion of the blade is involved, and frequently at the base. Petioles are very frequently attacked, and are then often hypertrophied. The main stalks are not so often attacked, but when this happens they are frequently very greatly hypertrophied, especially when the attack is at a node (Fig. 7). When the leaf-blade is attacked usually very numerous coalescing minute circular pustules are formed on the under surface, the upper surface opposite being pale or somewhat reddish. When attacked areas are small they are usually convex above, the lower concave surface bearing the spore-pustules. These spore-pustules are some- times so closely aggregated that on superficial examination it would appear that the whole patch of spore-extrusion is one large spore-bed. Sometimes a few pustules burst from the upper leaf surface ; but this is uncommon. When the leaf- blade is extensively attacked it is observable that the main nerves are thickened, showing a tendency for the mycelium to run along the vascular structures. On the petioles and stems the pustules are oval, and do not tend to coalesce so readily, due, to some extent I believe, to the extension of surface by hypertrophy. The spores are very deciduous, falling off with only a frag- ment of stalk adhering. They are brown, rounded at both ends, with little or no constriction at the septum, and very uniform in size. The epispore is not thickened anywhere (though a very slight colourless tubercle at the free end may be seen in most) and is beset over both cells with warts or tubercles, not densely aggregated, those over the lower cell being somewhat finer than those over the upper (Figs. 2, 3). Spores are frequently found divided into three and four cells, naturally suggesting a comparison with Phragmidium (Fig. 5). Each cell exhibits a well-marked nuclear space. The fresh spores just moistened measure 30 x 16 — 18 /x. On germination each cell throws out a short colourless promycelium, dividing as usual into four parts, each bearing a sporidium at the end Puccinia Geranii silvatici , Karst . . 35 of a fairly long sterigma (Fig. 2). When germinating while floating on the surface of water the promycelia are frequently aerial. The upper promycelium emerges from the apex, while the lower comes from a point near the stalk, and not as usual from near the septum (Figs. 2, 3). This displacement of the germ-spore from near the septum to near the stalk is inter- esting as being the reverse of that which obtains in the spores of Gymnosporangium , where the same thing occurs in the upper spore-cell. I know of only one other Puccinia which exhibits this peculiarity, namely P. W attiana on Clematis puberula (Fig. 4). The sporidia are oval and colourless and measure 14 -13x7- 6 [i. Secondary sporidia are sometimes formed, but not frequently. Having obtained specimens of P. Geranii silvatici , Karst, through the kindness of Dr. P. Dietel, gathered in the Engadine (St. Moritz and Pontresina), I compared it carefully with the Simla species. In general habit the two species appear to be very much alike, but the microscopic characters of the spores differ somewhat. In the first place I convinced myself that the surface of the lower cell is not tuberculated as a rule in the European species (Fig. 6) ; and in the second place the spores are larger, measuring (according to my own measurements) 33 — 24x21 — 18/x after lying twenty-four hours in water. These differences are, however, slight, and not sufficient perhaps to warrant their separation as distinct species. But the Himalayan fungus may be regarded as a distinct variety. 36 Barclay —On Puccinia Geranii silvatici> Karst . EXPLANATION OF FIGURES IN PLATE IV. Illustrating Surgeon-Major Barclay’s paper on the Life-history of Puccinia Geranii silvatici , Karst (var. himalensis ). Fig. i. Photograph showing result of artificial inoculation (experiment 12), natural size, photographed 17th May. Fig. 2. Teleutospore, showing tuberculation over both cells ; the upper with promycelium and sporidia (19th April) x 350. Fig. 3. Teleutospore, showing promycelia from both cells. Spore from experi- ment 11 (10th May) x 150. Fig. 4. Teleutospore of Puccinia Wattiana, Barclay, on Clematis puberula, showing promycelial formation as in fig. 3 (6th May) x 350. Fig. 5. Teleutospores divided into three and four cells (13th April) x 350. Fig. 6. Teleutospore from specimen from the Engadine, showing the upper cell only tuberculated, to compare with fig. 2 x 350. Fig. 7. Hypertrophied node, natural size. JlruiaZs of Botany Vol. VfPl.IV. A.Barclay del. University Press, Oxford. BARCLAY. ON PUCCINIA G E R A N 1 I - S I L V A T I C I , Karst., var. HIMALENSIS. On Isoetes lacustris, L. BY J. BRETLAND FARMER, M.A., F.L.S. Fellow of Magdalen College , Oxford. With Plates V and VI, and Woodcut i. EW genera amongst the higher series of plants have JL attracted more general attention and interest than that which has for so long been centred round Isoetes. Regarded as a study in taxonomic research, the numerous points of contact which it displays with families which are otherwise sharply severed from each other in affinity, are sufficient to justify its claims on the comparative morphologist, whilst at the same time the anomalous character of its structure has long afforded ample and fruitful material for histological in- vestigation. The object of the present paper is to attempt the elucida- tion of some of the numerous points of development and organogeny which have hitherto, in spite of the numerous workers in the field, baffled or escaped explanation, and also as far as possible to give a connected account of the oophyte whose development has long remained obscure, in the hope that further light may thereby be thrown on the difficult ques- tion as to the position of Isoetes in the natural system. Von Mohl 1, who may be said to be almost the first person who investigated carefully the structure of Isoetes , drew atten- tion to its more important peculiarities, such as the arrange- 1 V. Mohl, Ueber den Bau des Stammes von Isoetes lacustris, Linnsea, 1840; also Vermischte Schr. [Annals of Botany, Vol. V. No. XVII. December 1890.] 38 Farmer —On Isoetes lacustris , L. ment of the roots and the character of the cambium, and secondary thickening. Wahlenberg 1 seems to have been the first to notice the peculiar mode of thickening characteristic of this plant. His remarks are as follows : ‘ Caudex radicis constituitur taleola satis crassa quam nux avellanae saepe majore in ceniro vegetante et ad ambitum moritura .’ But with- out doubt to Von Mohl belongs the credit of having pointed out the fundamental differences existing between the stem of Isoetes and those of the other vascular cryptogams which were familiar to him. Alexander Braun2 further explained the relation of the leaf-arrangement to the conformation of the stem ; and he also correctly described the branching of the roots as dicho- tomous, although he does not seem to have grasped so clearly as Mohl their connection with the stem. The chief source of our information on the genus is to be found however in the classical memoir of Hofmeister3, in which the external morphology as well as microscopic struc- ture and development, as far as his opportunities admitted, are for the most part dealt with in a masterly manner. He was, it is true, in error in his statements as to the character of the apices of the stem and root, in which he believed he had found apical cells ; going so far, in the case of the stem, as to correlate the mode of segmentation with the 2- or 3-forking of the stem. Naegeli and Leitgeb4 also came to the conclusion that the root-apex was dominated by a 2-sided apical cell, although they confess that their view is based on negative rather than on positive evidence, and is arrived at after re- jecting other apparently possible explanations. Their figures, like Hofmeister’s, were wonderfully accurate, and later ob- servers have not always paid them the attention which they deserve. The results of my own investigations will, I hope, 1 Wahlenberg, Flora Lapponica, p. 264. 2 Alex. Braun, Weitere Bemerkungen ueber Isoetes, Flora, 1847. 3 Hofmeister, Beitr. zur Kenntniss d. Gefasskryptogamen, Abh. Math. Phys. Kl. d. Kon. Sachs. Gesell. d. Wissenchaften, 1857. 4 Naegeli u. Leitgeb, Entstehung u. Wachst. d. Wurzeln, Beitr. zur Wiss. Bot. iv. Heft, 1868. Farmer.— On Isoetes lacustris , L. 39 show the source of their misconception of the structure of the apex. The structure and development of the Stem. — As far as the structure of the stem is concerned, however, it is much more difficult to understand on what grounds it was possible for so careful an investigator as Hofmeister to describe its growth as regulated by an apical cell. At no time is any cell-arrange- ment perceptible which would warrant this conclusion, and if the appearance presented by sections cut parallel to the furrow of the stem occasionally seems to point to it, more careful study of a series invariably leads to an opposite result, and clearly shows that the mistake is referable either to the ob- liquity of the section or to the fact of its having passed through the base of a leaf-rudiment. Comparison of trans- verse with longitudinal sections fully confirms this observation (PL V. Figs. 11, 13), and further affords proof that the apical meristem is even less regular than is the case in the Lycopo- diaceae, judging at least from the figures published by Stras- burger 1 and others. The entire apex of the stem is covered by a columnar layer of cells which divide chiefly anticlinally, periclinal divisions only occurring at rare intervals, a fact which is to be connected with the slight increase in length of the stem. I endeavoured to find out if the frequency of the periclinal divisions bore any relation to the number of leaves formed, but have been unable to ascertain that any such connection exists. The cells which lie beneath the su- perficial layer, though irregular in size and shape, indicate, in their general arrangement, a conformity with Sachs’ law. Hegelmaier2 and Bruchmann3 have regarded the bundle of the stem as consisting partly of a sympodium of leaf-traces, and partly of a cauline portion, represented by xylem-elements derived from a supposed plerorne-tissue which surmounts the woody portion of the bundle. A comparison of a great 1 Strasburger, Coniferen u. Gnetaceen, Taf. xxv. figs. 29, 30. 2 Hegelmaier, Zur Kenntniss einiger Lycopodinen, Bot. Zeit. 1874. • 3 Bruchmann, Ueber Anlage u. Wachst. d. Wurz. bei Lycopodium u. Isoetes , Jen. Zeitsch. fur Naturwissenschaften, VIII. 40 Farmer . — On Isoetes lacustris , L, number of sections has however convinced me that Hof- meister’s view is more in accordance with the facts, and that • the axile bundle is really made up of leaf-traces, a view in which De Bary 1 also concurs. But in this case, like the alleged exogenous nature of the first root, to be considered subse- quently, there is represented just one of those transitional stages where distinctions lie rather in the mind of the investi- gator than in the actual object before him. In this particular instance it is exceedingly difficult to draw a limit between a possible cauline and a common bundle in the older stages, although in young plants it is perfectly obvious. The cause of the discrepancy existing between the accounts of the various writers possibly lies in the great difficulty, without a complete series of sections, in reconstructing the entire vascular system with any degree of accuracy, and the difficulty is further increased by the great number of leaves which arise at almost exactly the same level on the stem. About a year after germination, when the first few leaves are fully formed, the parenchyma around the vascular bundle of the stem (the pericycle of Van Tieghem) begins to divide periclinally to form the ‘cambium.’ The divisions extend around and above the axile bundle of the stem, but not so far as the youngest leaf-traces. And thus, whilst agreeing with Hegelmaier in the main features, I cannot but think that his description is misleading when he states that, whilst the cam- bium extends above the bundle in the form of a barrel, those cells which take part in the formation of a leaf-trace change their direction of division to one at right angles to that of the surrounding cells, in order to contribute to the trace. This statement is however only true of the appearance presented by older leaf-traces, which have become surrounded by, and enclosed in, the cambial zone. Originally, as I have said, the particular direction of their division is determined before the cells in their vicinity assume the freshly active merismatic condition. The leaf-trace originates in the division of a row of cells, in 1 De Bary, Comp. Anat. p. 280 (Engl. Trans.) Farmer —On Isoetes locus tris , L. 4i an upward and outward direction, which more or less irregu- larly connect the base of the leaf-rudiment with the central part of the stem, at the apex of the woody portion of the bundle. Thence the division extends upwards into the leaf and downwards into the stem. In all cases where I have been able to observe accurately, the tracheids of the trace are seen to join the axile strand in such a way as to afford conclusive evidence that they, with the tracheids of the neighbouring traces, form the entire mass of wood. No xylem-elements, so far as I could determine, are ever present above the insertion of the last leaf-trace. The elements of the wood in the vascular cylinder of the stem are very short as compared with the corresponding cells of the trace, and are largely mixed with conjunctive paren- chyma. At a short distance below its summit, the axile cylinder of vascular tissue in the stem shows signs of irregular splitting, owing to the disruption of its cells, and the whole structure rapidly becomes full of intercellular spaces. This result is indirectly brought about by the activity of the cam- bium. The traces of the roots and leaves which pass through this zone to join the axile vascular cylinder are subjected to great strain by the fact that whilst the cells round them are growing, and, so to speak, travelling outwards, they themselves are stationary, and can only increase in length by extension. This takes place to a limited extent, and effects a great dis- tortion of their constituent cells, but finally the loose central tissue gives way, and they are partially relieved of the strain at the expense of the cohesion of the inner tissue. That such really represents the actual state of the case may be ascer- tained by inspecting longitudinal sections through parts of the stem where the process is being vigorously carried on, and it is indicated by the character of the cells in the photograph (PI. VI. Fig. 27). It is difficult to assign any other reason for the occurrence, mere extension of the cells of the stem will at any rate give no explanation. The cambium formed as above described, besides giving off cells peripherally, produces also the so-called prismatic cells 42 Farmer. — On Isoetes lacustris , L. at its interior, which are continuous above with the phloem of the leaf-traces. Russow partly for this reason, has regarded the prismatic layer as representing a bast or phloem, but quite apart from the fact that it is produced internally to the cam- bium, and would thus, from the point of view of its position, be anomalous, its structure is remarkably complex and hetero- geneous. Hegelmaier2 briefly indicated the zones observable in the tissue under consideration and assigned the cause of the appearance to alternating layers of clear and starch-filled cells. Transverse sections taken through the central part of the stem show that the prismatic layer which surrounds the central xylem is a band of varying thickness, being especially inter- rupted by the bundles which pass out to the roots. The zone- like arrangement consists in alternations of tubular thin-walled cell-rows of varying thickness, whose cell-contents are clear and watery, with others, wThose cells are wider in the radial direction, and filled densely with starch. Occupying a middle position in the latter zone, is embedded an irregular ring of cells whose walls are thickened like those of the tracheids, but these too, unlike the latter, often contain protoplasm and starch. (The dark bands in PI. VI. Figs. 26 and 27.) The number of the zones or bands varies with the thickness of the stem, and therefore presumably with its age, and also with the height at which the section is cut. The longitudinal sec- tion is especially instructive in explaining the relation which exists between the number of the zones at different heights. The bands are seen to converge towards the axile xylem in the order of their position ; the outermost one being of course inserted highest. Their relative position naturally suggests some connection between their number and the periods of active growth, but I am unable to say if such a connection really exists. Fig. 27, which is a photograph of a section of /. velata , for the material of which I am indebted to the kind- ness of Prof. Pirotta, shows the longitudinal arrangement of the bands through part of their length. 1 Russow, Vergl. Unters. p. 139. 2 Hegelmaier, loc. cit. Farmer —On Isoetes lacustris , L. 43 The cells lying between the apical merismatic layer of the stem and the xylem of the vascular bundle evince, as has been already said, a general convergence towards the apex, and it is at the periphery of this mass that the cambium is first differ- entiated, and it is gradually pushed outwards below by the products of its own activity. Hence, as in the higher plants, radial divisions are essential to admit of the attainment of the increased circumference which the zone occupies. There are two methods whereby these radial divisions are effected : (i) Either, a cell of the cambium divides into two equal halves X A \ V ABC Fig. i. Diagram of transverse section of cambial cells. in the radial direction, and then each of the two sister-cells divides henceforth tangentially in the usual manner to form the secondary tissue (see Fig. A below) : (2) Or, a cambial cell divides into unequal sister-cells by a wall which cuts one of the radial walls and the inner tangential wall, and then the first succeeding divisions are not quite tangential, but are curved to meet the rounded cell-wall ; but finally the r esult is the same as in the first case, though the products can be more easily traced, at any rate inwards, on account of the pointed end by which such a cell-row is always characterised (Figs. B, C, above). These two modes of division are however 44 Farmer. —On Isoetes lacustris, L. only extreme forms of the same process, and all conceivable transitional stages may be met with in good preparations, that is, the radial wall of (i) may incline more or less from the truly radial direction, until it passes over into the form of (2). Around the apical meristem of the stem are situated the young leaves which originate as horseshoe- or crescent-like protuberances from the apical tissue. As is well known, they arise exclusively as outgrowths of the superficial layer of cells, and this point has been noticed as in some degree weakening the suggested resemblance to the Cycads, in which the peri- blem also enters into the formation of the leaf. It is however, I think, open to question how far this fact is of weight in either direction, for in Cycas the dermatogen and periblem of the stem lose their individuality in the actual apex, originating from a common layer of cells 1. If however it were wished to press the resemblances, Isoetes might be regarded as an in- stance where this suppression of the individuality extended beyond the point of origin of the leaves, thus making this genus occupy a position as regards Cycas analogous to that of Cycas as regards the Abietineae. The Leaf and Ligule. — The leaf, after the rudiment is formed, by the luxuriant growth of the superficial cells, increases rapidly in size, and is at first completely enclosed by the sheath of an older leaf, which thus forms a kind of tube for its protection. The ligule is early discoverable at its base as a protuberant cell containing a nucleus of a very large size. It grows quickly, but never attains, in I. lacustris , to the propor- tions which it assumes in some other species, e.g. I. velata . In this latter plant it develops far more rapidly than the leaf which produces it, and, overtopping it, curves over the apex in such a manner as to protect the whole of the upper part of the leaf. The marginal cells of the expanded upper portion of the ligule are prolonged into short finger-like processes which not improbably contain a mucilaginous substance, and thus serve as additional means of protection against possible periods of dryness. In I. lacustris the ligule is, comparatively 1 Strasburger, Coniferen, etc., pp. 335-6. Farmer —On Isoeies lacustris, L. 45 speaking, but little developed, and there Is moreover In this plant no apparent need of special protection, especially as the older leaves so securely shelter the younger ones. It is only in exceptional cases that I have met with any prolongation of a few of its terminal cells at all comparable with that in I. velata , and the whole structure Is smaller and simpler than in that plant. It is of course known that the slow-growing leaves of Ferns are commonly provided with some protective structure, and they may be regarded as representing the means for satisfying In a simple manner those requirements which in the higher plants involve the modification of potential foliage- leaves1, stipules, etc. into scale-leaves. Without desiring to press the point too far, It may be noticed that these modifi- cations are especially characteristic of the highest orders of plants, i. e. Phanerogams, and that in the lower members, such as Cycasj in which the early steps may be perhaps supposed to be observable, the arrangement is not such as to suggest that economy of material which is commonly to be seen in adaptive modifications. The stipules of Marattia and the curious structures described by Holle 2 for the Ophioglossaceae are familiar examples of the more complicated kinds of pro- tective structures met with amongst the Vascular Cryptogams, whilst the simpler forms of the series are represented by the r amenta of so many Ferns. Much has been made of the ligule in Isoetes as indicating some affinity with Selaginella in which a similar structure occurs, but the two are In reality very different ; that of Selaginella arises not from one cell, as in Isoetes , but as a multi-cellular protuberance ; the mature struc- ture Is, moreover, not nearly so complete as in Isoetes , especially as regards its insertion. The point, however, which specially weakens the grounds for basing any theories of affinity on the common possession of the ligule by the two genera, is the much later development of this structure in Selaginella than In Isoetes . And even if this were not the case, outgrowths of a similar nature and belonging to the same category are so 1 Goebel, Beitr. z. Morph, u. Physiol, des Blattes, Bot. Zeit. 1880. 2 Holle, Ueber Ban u. Entw. d. veg. Organe d. Ophioglosseen, Bot. Zeit. 1875. 46 Farmer. — On Isoetes lacustris, L. numerous in plants otherwise widely distinct, that it appears scarcely legitimate to regard them as affording any other but confirmatory evidence in establishing a theory of relationship which has been already arrived at on broader grounds. It is of course well known that outgrowths of a somewhat analo- gous nature are found to be often remarkably constant in certain circles of affinity, such for instance as the stipules of Rosaceae and of Cupuliferae. But this fact really strengthens the case against the employment of the ligule of Isoetes as affording any evidence of affinity with Selaginella, for no one will refuse to admit that the relationship between the two is at the best but very remote, so different are they in all other important characters ; to endeavour therefore to unite them on account of the presence of a ligule in each of them, even if this structure were more similar in the two plants than as a matter of fact is the case, is like an attempt to establish an affinity between the Rosaceae and Cupuliferae on the ground that stipules are common to both orders. Development of the Leaf. — In describing the development of the leaf, it will be convenient to consider in the first place its growth in length. After its rudiment has become well pro- nounced as a flattened and conical papilla, further cell-division is chiefly restricted to a zone situated at or near the base of the young leaf. In plants in which sporangia have begun to be formed, the cells below the insertion of the ligule remain for some time merismatic, and thus space is provided for the large sporangium, and at the same time the zone, including the insertion of the ligule, is raised up. If, on the other hand, the leaf belongs to a plant which has not as yet begun to bear sporangia, the merismatic tissue is localised in the part of the leaf immediately above the ligule. This position is ultimately taken up by the merismatic tissue of all leaves, and it is to the activity of cell-division in this region that the greater part of the mature supraligular portion owes its existence. The cells which are thus formed differ in their subsequent growth, and thus differentiation is at an early period per- ceptible in the leaf above the meristem. Whilst the middle Farmer . — On Is oetes lacustris , L . 47 cells, which form the vascular strand, grow mainly in length, and remain of small diameter, the parenchymatous cells which immediately surround them as a double or triple layer divide rapidly in the transverse direction. The same is also true of the two rows at the periphery of the leaf, although in this respect they exhibit certain minor differences (see PL V. Fig. 16). If the section has passed through the leaf in a direction other than that of the median plane, or one at right angles to it, the cells which occupy the space between the central strand and the periphery are seen to grow quite differently from the tissues on each side. They divide freely whilst in the merismatic region, but after emerging from it they scarcely increase in size at all and their nuclei are very small, a fact which is probably to be correlated with their arrested growth and extremely thin walls. Owing to this condition, and to the fact that the surrounding cells are largely increasing in length, the stationary cells are torn asunder in the longitudinal direc- tion, cohesion being first lost at the centre, whilst the peri- pheral cells remain permanently attached by their transverse walls : in this way are formed the diaphragms which cross the four air-chambers found in the mature leaf of the plant. The diaphragm is thinnest at its centre, i. e. is of double concave lens-shape, and consists usually of only one cell-layer at this point, becoming thicker at the edges where it is suddenly inserted ( sit venia verbo) on the outermost layer of the cells which were concerned in its formation (Fig. 16 in PL V). The earlier periclinal divisions which occur in the leaf are better seen in transverse than in longitudinal sections. ' In transverse sections of young leaves in which the central strand has not as yet reached its final stage of differentiation, but which is, however, perfectly distinct, the outer cells of the leaf are seen to be increasing rapidly by periclinal or tangential divisions, which occur very regularly, and for the most part centrifugally. This is well illustrated by the photograph (PL VI. Fig. 22), in which the slight difference which exists between the development of the inner and the outer surfaces is already visible. It is only at a later stage that the diaphragm- 48 Farmer.— On Isoetes lacustris , L. cells become clear and marked off from the four rays of parenchyma which always connect the central bundle with the periphery of the leaf (PL VI. Fig. 23). Division is not so regular in the lower part of the leaf, where the sheathing portion is formed as a wing-like outgrowth, which is rendered more evident as the base of the leaf becomes elevated above the level of the stem. The bundle of the leaf in its subulate portion pursues a straight course, and, bending out behind the insertion of the ligule, where also its character slightly changes, it finally curves inwards again below it, and passes as a trace into the stem. It is rudimentary in structure, but of very constant form, and is collateral, both in its course in the leaf and also after entering the stem, thus indicating a relation- ship with the higher Ferns and with the Phanerogams. In the portion of the leaf near the apex, the lignified portion of the xylem is reduced to a single tracheid, which is sur- rounded by six or eight parenchymatous cells, representing the rest of the xylem, which occasionally suffer more or less complete lignification, especially in the lower part of the leaf. I am unable to confirm Russow’s statements as to the development of the xylem ; I do not find, at least in /. lacustris , that there is any definite direction in which the fresh xylem- elements are produced. Sometimes they are formed centri- petally, sometimes in the opposite direction, and occasionally they spread unequally in the lateral direction. The phloem is represented by a few cells which occur at the outer flanks of the xylem, and the protophloem tissues, where they can be distinguished, occur as distorted elements at the outer side of the wood. This slight tendency to encroach around the xylem is of interest, as pointing to an approach to the concentric type of the Fern-bundles proper ; it is shown in PI. V. Fig. 15, which was drawn with the camera lucida. I failed entirely to discover any sieve-plates in the phloem either of I. lacustris or /. velata ; possibly, however, they might be found in a more pronounced terrestrial form. The elements of the xylem become more numerous as the bundle bends out behind the ligule, and at the same time much shorter ; a fact Fawner. — On Isoetes lacnstris, L. 49 which is to be accounted for by the slight increase in length of the cells of this region. The arrangement both of xylem and phloem is also here obscured, and the curvature makes it almost impossible to determine their exact relation, though it is improbable that they differ from that already described for the upper part of the leaf. The Sporangium. — The development of the sporangium has been so admirably worked out by Goebel1, who has corrected and extended the observations of other investigators, that I have nothing to add to his results, which all my own work has confirmed. A comparison with some of the younger stages of /. velata and /. Hystrix has not yielded any new matter of importance, though it is not improbable that a more extended comparative research may throw light on the ques- tion as to the uni- or multi-locular nature of the sporangium in this genus. The facts are, briefly, that each hypodermal archesporial cell has a separate and individual growth ; that certain of these form the sterile trabecular tissue, whilst the others form the sporogenous tissue. The exact development of the latter varies according to the macro- or micro-sporangial nature of the body in question. The tapetum in both cases is derived partly from the sporogenous archesporial cells, partly from the trabeculae, and, according to Goebel, partly also from the cells at the back of the archesporium : my observations have made me a little uncertain on the latter point, but it is in any case of no great morphological import- ance, as is shown by the variation which exists in this respect in Phanerogams. The trabeculae, then, really appear to serve two functions ; first to provide a large amount of the tapetal nourishment, and secondly to provide a support for the outer wall of the somewhat bulky sporangium, and indeed from the close manner in which the leaves are packed together on the stem and the mutual pressure they must exert, it is probably a matter of some importance that some such protection should be supplied. The formation of sterile tissue, which is homo- logous with the actual sporogenous tissue, is well known in the 1 Goebel, Beitr. z. vergl. Entw. d. Sporangien, Bot. Zeit. 1880. E 50 Farmer, — On Isoetes lacustris , L. Hepaticae, and it reaches its highest expression in forms like Dendroceros , in which there is a distinct resemblance to Isoetes. Of course, the sporangia of the Marattiaceae naturally suggest the explanation that the trabeculae represent the sporangial walls, but the inspection of a tangential section through a half- matured sporangium, especially of a micro-sporangium, tends to weaken the value of such a comparison. In any case, how- ever, it must of course be admitted, that if Isoetes is actually allied, as I am convinced it is, with the Eusporangiate Ferns, the exceedingly common occurrence in them of numerous sporangia in close proximity would offer a contrast to Isoetes with its single sporangium. Such divisions in the sporangium as are formed by the trabeculae are not unknown in Phanero- gams— in certain Onagraceae, for example — but I cannot regard this fact as in any way tending to establish the multi- locular nature of the body in Isoetes. The Root. — As regards the root, hardly two writers agree in their accounts of its structure and development. The facts that its apex ceases at an early age to remain in the meris- matic condition, and also that the dichotomy of the apex takes place repeatedly while it is still enclosed in the original root-cap, serve to render the task of understanding its structure one of considerable difficulty. Hofmeister, as is well known, regarded its growth as taking place by means of an apical cell, and Naegeli and Leitgeb also assumed its presence, although on negative rather than positive grounds. It is difficult to see how they missed the more correct explanation : their figures are extremely good, and they actually succeeded in unravelling some of the more difficult points, one of which, the nature of the plerome-initial, it is not easy to reconcile with any apical cell hypothesis such as they put forward : ‘ Der Cambiumcylinder ist anfangs immer einzelligV Bruchmann2, who studied the root in detail, believed he had succeeded in demonstrating three 1 Naegeli u. Leitgeb, Enst. u. Wachst. d. Wurzeln, Beitr. z. wiss. Bot. 4. Heft, p. 134. 2 Bruchmann, Ueber Anlage u. Wachst. d. Wurzeln bei Lycopod. u. Isoetes , Jen. Zeitsch. fiir Naturwiss. VIII. 1874. Farmer.— On Isoetes lacustris , Z. 5i histogenic layers at the apex, a calyptro-dermatogen, a double cortex or periblem, and a plerome. He practically confirms Naegeli and Leitgeb’s previous description, when he says, * Das Plerome wachst im wahrsten Sinne des Wortes mit einer Scheitelzelle,’ although the investigators just mentioned had not apparently foreseen the conclusion to be drawn from their own observations. Kienitz-Gerloff1 *, on the other hand, after criticising the views of his predecessors, arrives at the singular conclusion that the apex is occupied by an undifferentiated meristem : 6 Am naturgemassesten scheint es mir . . . das Gewebe der Wurzelspitze von Isoetes als ein vollig indiffe- rentes Meristem zu betrachten. In dem durch dieses Meristem abgeschiedenen Gewebe sondern sich dann spater die verschie- denen Gewebesysteme aus ’ (p. 793). He was probably led into this error by confining himself to a study of optical sections of cleared apices, otherwise his account can hardly be explained at all. His figures do not give the correct relations which exist between the different tissues : the derivatives of the plerome-initial never appear to run straight down the root, as he represents them, except when seen in a plane at right angles to that in which it is alone possible to draw any correct inference as to their origin. And even some of Bruchmann’s figures are open to question on this account. The latter investigator does not seem to have paid sufficient attention to the stronger roots of older plants, and I find myself unable to agree with him in his attempt to draw a sharp line of demar- cation between the periblem and the meristem which lies externally to it. I have invariably found the sharpest distinction to prevail between the inner and outer cortex (see PI. V. Figs. 9, 10; PI. VI. Fig. 30), while the outer layer of periblem-initials are in most cases not clearly separable from the layers giving rise to the epidermis and root-cap. The variation which seems to exist on this point is suggestive, taken in connection with the relation existing between the dermatogen and periblem 1 Kienitz-Gerloff, Ueber Wachst. u. Zelltheil. und d. Entwickl. d. Embryo von Isoetes lacustris , Bot. Zeit. 1881. E 2 52 Farmer . — On Isoetes lacnstris , Z. in the Gymnosperms, in or Pimts , for example. The plerome, in all cases where I have been able to trace it clearly, grows certainly from a single initial cell, but from the excentric course which the pro-cambial cylinder pursues in the root, it is by no means easy to secure sections which pass through it in the right plane. The cells which are cut off behind the irregularly shaped cell at the apex are readily distinguishable on account of their large nuclei and proto- plasmic contents, as well as their large size as compared with the surrounding cells. The cells thus forming a row, divide peripherally and longitudinally, leaving a much larger central cell, from which further cells are cut off longitudinally ; this is figured by Hofmeister1, and also by Naegeli and Leitgeb2, and in both cases with remarkable accuracy. Hofmeister explained the large cell as the apical cell, but a series of trans- verse sections shows this view to be untenable (see PL V. Figs. 5v 6, 7, 8), and longitudinal sections (Figs. 9, 10, 30) also demonstrate clearly the actual state of the case. Hofmeister s sections were cut, as a matter of fact, below the actual apex of the plerome, and show the early stages of the development of the vascular bundle. The photograph (Fig. 30) shows how large the central cells are in proportion to those surrounding them, and also how they retain the dense protoplasmic con- tents and large nuclei which are commonly associated with merismatic structures. The xylem-elements of the monarch vascular bundle only make their appearance at a relatively late period. The two photographs (Pigs. 38, 29) show pretty clearly the stages by which this is brought about ; and they also show how the phloem-portion of the bundle is well differ- entiated before the xylem, which is not as yet formed in either, although in Fig. 29 its general future position is distinguishable. There is no need to further discuss the structure of the mature portion of the root, it having been sufficiently described by other investigators, and the split in the cortex has also been correctly explained by Bruchmann. As to the origin of the lateral roots from the stem, I have as yet been unable to 1 Loc. cit. Plate XIII. Figs. 3, 4. 2 Loc. cit. Plate XIX. Figs. 3, 6. Farmer. — On Isoetes lacnstris, L. 53 investigate this point independently, although the statements made in reference to it by Van Tieghem and Douliot 1 leave the matter in some doubt. I cannot, however, agree with these authors in regarding the cortex of the root as referable to a single layer of periblem-cells, nor do I find their figure (PL XL. Fig. 583) at all convincing. It does not represent anything like that which I have seen in perfectly median sec- tions where the distinctions of the different tissues are much more clearly marked than in their figure, in which the plerome is very much larger in proportion to the size of the whole root than in any preparation I have met with. I have been unable to follow out all the stages of the dichotomy of the root, but so far as my observations extend, they confirm Bruchmann’s statements on these points. As regards the exogenous character of the primary root my results are, in the main, in agreement with those of other writers ; the first divisions certainly occur in the superficial layer of cells, and the inner of the two daughter-layers formed by this periclinal division again divides, giving off fresh root- cap-cells at its exterior. The inner meristems are, however, formed from cells within this layer, which only forms the outer cortex, as is partly indicated in PI. V. Figs. 2, 3 ; and Kienitz- Gerloff also has arrived at the same result. The outer layers of the root are as a matter of fact exfoliated, and relying on this fact, the author just cited argues against the claims of the root to be regarded as exogenous. The difference between exogeny and endogeny in a structure such as this is, however, some- what shadowy, and perhaps it would be well to regard it as representing actually a transition between the two. Of course many (comparatively speaking) exogenous roots are now known, amongst which may be quoted that of Phylloglossum. Van Tieghem and Douliot have attempted to correlate the relative time of development with the exo- or endo-geny, but I think that the instance of Isoetes shows that this principle, useful as it is in many cases, may be carried too far. The root 1 Recherches comparatives sur Forigine des membres endogenes dans les plantes vasculaires, An. Sci. Nat. (Bot.) 1888. 54 Farmer . — On Isoetes lacustris, L. of Isoetes is not perhaps, strictly speaking, a primary structure, and I incline rather to consider it as an early type of adven- titious root. It is formed relatively much later than in the true Ferns, and yet it is far more exogenous in character than in them. The Oophyte . — The development of the oophyte has long presented difficulties to those who have attempted its investi- gation, partly owing to the ease with which the contents of the spore are injured, and partly to the hardness and thickness of its coats. Mettenius 1, who described the structure of the macrospore, correctly distinguished its three principal layers or coats. The outer glassy epispore or perinium is extremely hard and brittle, and its surface is beset with numerous prominences. It is without doubt derived from the plasma of the sporangium formed by the breaking down and solution of the tapetal cells (and probably the mother-cell walls), and it stains faintly with safranin. The exospore, a dark brown band of somewhat fibrous appearance, is clearly resolvable into a double layer, and the outer one of the two frequently splits again. The endospore is a rather thick cellulose-wall, of irregular thick- ness, and it is characterised by a brightly refractive appearance, recalling that presented by collenchymatous walls. The contents of the spore are rendered obscure by the enor- mous quantity of oil, the removal of which can however be easily effected by turpentine or ether, when the protoplasm appears as a granular and reticulated structure. The granu- larity is caused by the numerous small proteid bodies which are embedded in its substance, whilst the reticular structure is due to the withdrawal of the oil which formerly filled the meshes. Starch-grains are also freely present, so that the protoplasm is thus very richly supplied with nutritive reserve material. At the upper end of the spore lies the nucleus, which is of very large dimensions, and contains a variable number of nucleoli of different sizes. These points are illus- trated by the photographs (Figs. 24, 25). The nucleus, which 1 Mettenius, Ueber Azol/a, Linnaea, 1847, p. 269. Farmer. — On Isoetes lacustris , L. 55 is separated from the cytoplasm by a well-marked membrane, is of a very watery consistency, and is so poor in chromatin as to be scarcely stained at all by reagents more especially used for nuclear structure, as methyl-green, safranin, or haematoxy- lin, although the nucleoli are rapidly and intensely coloured ; and it is to these facts that the great difficulty of following out the changes which take place in the nucleus during the earlier stages of germination is to be attributed. In the mature spore the apical portion (in which the nucleus is imbedded) is clearly separable from the remaining larger part by the dense character of its protoplasm, and the com- parative absence from it of the reserve stores of starch and oil ; and this differentiation becomes more and more obvious as the formation of cell-walls approaches. I have not, in spite of careful search through many hundreds of spores, succeeded in recognising the nucleus at this stage ; probably the nucleoli, during its division, may suffer disintegration, and diffusion into the cytoplasm as the result of the heat necessarily employed in parafin-embedding. But although the changes in the nucleus remain obscure, the other processes attending germination are clear enough. The mass of protoplasm already mentioned as occupying the apex of the spore becomes traversed by fine cracks coinciding in their general directions with the positions ultimately taken up by the young cell-walls. I have no doubt that this splitting is subsequent to, and perhaps conditioned by, the division of the spore-nucleus, though direct evidence is wanting on this point. After cell-formation has begun, it proceeds with great rapidity, though in a manner differing in the two regions of the spore already alluded to. Figure 17 exhibits one of the earlier stages, and is intelligible when it is borne in mind that the section has passed obliquely below the spore-apex. Figure 1 8 shows clearly the differences in the process of division pre- vailing in the upper and lower part of the spore, the extreme slowness with which the process is conducted in the lower part being strongly contrasted with the rapid cell-increase in the upper portion. The divisions in the latter region lead to the 56 Farmer. — On Isoetes lacustris 3 L. formation of the archegonia, and so similar are the earlier formed cells of the outer layer all through this upper portion of the prothallium that it is impossible, until quite late, to pre- dict which are destined to give rise to archegonia ; all are apparently, and to an equal extent, potential reproductive- organ-forming cells. The archegonia are formed by the peri- clinal division of an outer cell into two daughter- cells, the outer of which forms the four (sometimes three) stories of neck-cells, whilst from the inner one are cut off successively the neck-canal- and ventral canal cells, leaving the oosphere at the base. While these divisions are taking place the surrounding cells divide into a small-celled tissue in which the archegonium is buried, only its outermost neck-cells being free. The venter is thus formed, as in the highest Vascular Cryptogams and Gymno- sperms, not from the mother-cell of the archegonium, but from the cells of the surrounding tissues. The neck-cell, when first cut off, divides into four cells arranged cross-wise, and then each of the four is divided into two cells transversely, and each of these again divides, once more forming the four stories of which the mature neck is commonly composed (PI. V. Figs. 20, 21). The neck-canal-cell grows in between the neck-cells, thrusting them apart, and establishing, eventually, a connec- tion between the exterior and the inner part of the archegonium. The neck-cell and the ventral canal-cell all finally become mu- cilaginous as in other Cryptogams. Whilst these changes are rapidly proceeding in the upper part of the spore, the larger basal portion also undergoes changes. Its protoplasm is never so abundant as that of the upper cell-tissue, but the reserve material stored up in it is far more plentiful. It forms a cellular mass, but comparatively slowly, beginning at the periphery, and fortunate preparations show the large peripheral cells enclosing a central mass of protoplasm, as yet undivided, but in which are lying several free nuclei (Fig. 19). The whole appearance recalls the free cell-formation taking place in an embryo-sac during the formation of endo- sperm, though there is nothing more than analogy between the final products in the two cases. The lower portion of the spore 57 Farmer. — On Isoetes lacustris , L. eventually becomes filled with cells which are always distinct from those of the upper portion, both on account of their size and their contents, and moreover they never form archegonia. The prothallium thus formed lies within the spore, but not connected with it, as its outer cells have their own external wall distinct from the endospore. The formation of the prothallium in Isoetes presents certain striking features of resemblance with that of Selaginella as described by Pfeffer 1, and may perhaps help to explain some of the peculiarities which render the oophyte of the latter plant so remarkable. Pfeffer states, and I am able to confirm his results in their chief points, that the spore is first divided by a wall (diaphragm) into an upper portion in which cell- division goes on rapidly, and a lower and much larger portion in which cell-formation is long retarded, and of which the protoplasm contains large quantities of food-material. The ‘ Prothallium ’ (of Pfeffer) makes its appearance before the spore has reached its full size, and is only followed later, after sowing the spores, by a free cell-formation in the infradiaphragmatic portion. Cell-division is brought to a close here apparently through the gradually increasing inability to complete the process, the lower part, as I have sometimes seen in 5. Braziliensis , still remaining undivided into cells when an embryo was already growing in the spore. Pfeffer has endeavoured to make a morphological distinction between the two kinds of tissue thus described, regarding the meniscus of small-celled tissue as the prothallium, and comparing the lower and looser mass to the endosperm of Angiosperms. I venture to think, how- ever, that such a position is untenable, and that the facts are to be better explained in another way, especially when Isoetes and Selaginella are compared in respect of their sexual generation. In both there is a clearly marked upper portion in which cell-division proceeds with great rapidity; and a larger basal portion in which cell-formation takes place slowly. That this production of cells proceeds centripetally in Isoetes 1 Pfeffer, Die Entw. d. Keimes d. Gattung Selaginella , Hanstein’s Bot. Abhandl. Bd. I. 58 Farmer.— On Isoetes lacustris , L. and basipetally in Selaginella I do not regard as a fact of great importance. The essential point is, that in each, a specially reproductive portion is separated from a specially vegetative and nutritive portion ; the chief difference between the two cases lying in the greater completeness with which the differentiation is carried out in the case of Selaginella. It is natural to expect that a tissue which is required rapidly to give up its substance to a growing organism would not form a small-celled tissue. This cell-wall formation would involve an uneconomical expenditure, and its occurrence in the endo- sperm of Angiosperms may perhaps be correlated with the comparatively slow growth of the embryo which obtains in these plants. Evidence is not wanting to show that a localisation of the reproductive organs of the oophyte, such as is required to support the suggested explanation of the structure in the two cases under discussion, is exactly the rule in a great number of widely different forms. This is especially true of the arche- gonia, with which we are here more directly concerned, and whose restriction to the ‘cushion’ of many Fern-prothallia, to the ‘ saddle ’ of Salvinia , to the central part of a Pilularia- prothallium, and to the more specially modified archegonio- phores of many other plants, in each instance points in the same direction, and still further support is given by the Equi- setaceae and the Lycopodiaceae. It might have been expected that Gymnosperms would evince a more decided distinction, if these conclusions are to hold good, between the reproductive and vegetative portion of their prothallia ; but apart from the fact that our knowledge on the early history of this structure in these plants is not very detailed, it may be pointed out that apparently the re- duction has become so advanced, so far as the reproductive bodies are concerned, in the higher forms at least, that not more archegonial rudiments are formed than can be brought to maturity. Further investigation in this direction would probably yield interesting results. I think that the above facts and considerations show plainly Farmer. — On Isoetes lacustris , L. 59 that Pfeffer was in error in regarding the ‘ Endosperm ’ of Selaginella as representing anything more than the vegetative or specially nutritive portion of the prothallium : the differences in the character of the cell-division in the two regions arising from the fundamental difference between the respective proto- plasms (in the widest sense of the word) which so modify the manner of cell-formation as to suit the ultimate requirements of each. I believe these conclusions may serve further to throw light on the question of the significance of the changes which occur in the embryo -sac of Angiosperms up to the period when the oosphere is ready for fertilization. Just as in Selaginella and Isoetes the first divisions of the spore separate the reproductive from the vegetative protoplasm, each of which thenceforth de- velops on different lines, so also the first division of the nucleus of the embryo-sac produces two daughter-nuclei, whose further products are perfectly dissimilar, resulting finally in the pro- duction of the ‘ egg-apparatus ’ at the one end, and the anti- podal cells at the other, with the definitive nucleus half-way. The antipodal cells do not, I believe, represent the whole prothallium, as they are usually considered to do, but only the reduced vegetative portion of it. And it would seem that the reduction has progressed so far that the original vegetative part is unable to, or at least does not, fulfil the needs of the growing embryo as regards nutriment, and hence the coales- cence of the two nuclei, one from the reproductive (micropylar) and one from the vegetative (antipodal) part of the pro- thallium. The definitive nucleus, formed in this manner, may probably be regarded as the result of a coalescence of nuclei analogous to that which obtains in actual fertilization, but with this difference, that in this case it is not an oosphere, but probably the second polar body , which descends from the generative apparatus and fuses with a vegetative nucleus which is derived from the opposite end of the spore. The union does not confer great power on the resultant nucleus : merely that of forming, under certain conditions, a number of similar cells — the endo- 6o Farmer . — On Isoetes lacustris , Z. sperm. It may be that the one nucleus contains sufficient histogenic plasma (to borrow Weismann’s expression) to enable, under suitable circumstances, the ‘reproductive sub- stance’ provided by the other nucleus (the sister-nucleus of the oosphere) to go through that simple form of segmentation which characterises the endosperm of Angiosperms. This view of the matter makes the micropylar nucleus, be- fore it divides into the four nuclei which compose the original ‘ egg-apparatus,’ the equivalent of the ‘ central cell’ of a Fern- archegonium; it cuts off successively two polar bodies, of which the first gives rise to the synergidae by further division, just as the neck-canal-cell of Ferns commonly divides further, after its separation from the central cell ; and the second one, which I regard as representing the ventral canal-cell of the Fern, forms half the definitive nucleus. It is true the existence of a ventral canal cell has been denied in the case of some plants, but the point requires renewed investigation. And there is nothing surprising in such a reduction of the generative apparatus in the highest plants ; such a process is indicated all through the various lines of descent of the different branches of Vascular Cryptogams, as well as of the Gymnosperms. In the Angio- sperms indeed, bearing in mind how the tissue for the support of the growing embryo is not even capable of developing unless there is a chance of its being used, and also how this principle of saving material is carried yet further in the case of ovules of many Orchids, such a reduction as actually occurs in the embryo-sac is not only possible but inherently probable. If these conclusions be accepted, Isoetes becomes additionally interesting as throwing light on some of the most obscure phenomena prevailing in Angiosperms. Its connection with Selaginella is equally interesting, as serving to explain the peculiarities of the sexual generation of this plant, but I do not regard the approximation in the character of the two oophytes as affording any weighty arguments for placing them near each other in the natural system. Rather we have an indication of one of those ‘parallel developments/ which are Farmer . — On Isoetes lacustris, L. 61 hinted at in so many other forms. The reduction of the oophyte has advanced along similar lines, wherever it has occurred, in the Vascular Cryptogams, and in the direction indicated above ; and it is from broader and more general comparative and morphological characters that the criteria of affinity must be derived. It is acknowledged by all modern writers that in reality Isoetes presents but little affinity with Selaginella. Goebel has even stated his belief that the ligule is perhaps the only important feature which they have in common, and I have attempted to show that the admitted community in this re- spect does not really advance the question at all. I myself entirely admit the force of Prof. Vines’ 1 arguments in support of the affinity with the true Ferns, and I think that the general results contained in this paper do not in any way oppose such an alliance, although they show that it is not perhaps very close. This is however not a matter for surprise ; the hetero- sporous character of the genus clearly indicates a great advance on the homosporous condition of the Filicinae. Annals of Botany, vol. ii. 62 Farmer —On Isoetes lacustris, L. EXPLANATION OF FIGURES IN PLATES V AND VI. Illustrating Mr. Farmer’s paper on Isoetes lacustris. (N.B. — Figures Nos. 26 and 27 refer to I. velata.) PLATE V. Figs. 1, 2, 3. Sections through the root of the embryo. The lines through the small diagrams accompanying Figures 1 and 2 represent the direction of the section, which lies in the plane of the paper in Fig. 2. Fig. 4. Transverse section through the vascular bundle at the base of an old root. Figs. 5, 6, 7, 8. Transverse sections through young root-tips at successively greater distances from the actual apex. Fig. 9. Longitudinal section through young root apex. P— plerome. Fig. 10. Longitudinal section through another root apex. P= plerome, E ~ der- matogen. Figs. 11, 12. Transverse sections of stem-apex. Fig. 11 shows superficies; xxxx the meristem ; L a leaf rudiment. Fig. 12 from the same stem, but the plane of the section lies deeper than in Fig. 11. Figs. 13, 14. Longitudinal section of stem with young leaf. Fig. 15. Vascular bundle of leaf. x = xylem, Ph — phloem, s = sheathing cells of the xylem. Fig. 16. Longitudinal section through half a leaf. E = epidermis. The large cells on the left abut on the vascular bundle which is not shown. Figs. 17, 18. Stages in germination of macrospore. Fig. 19. Section through a spore cut parallel to the base. Figs. 20, 21. Archegonia. PLATE VI. Fig. 22. Transverse section through young leaf, L. This is enclosed in the ligule {Li) of the next oldest leaf, and this again by that of a still older one. x = tracheid. Fig. 23. Transverse section of leaf, x = tracheid. Fig. 24. Section through a spore, n — nucleus, k — nucleolus, j = starch. Fig. 25. Another spore, with well-marked nucleus and nucleoli. Fig. 26. Transverse section of stem of Isoetes velata . Fig. 27. Longitudinal section of the same. Fig. 28. Transverse section of root of Isoetes lacustris just beneath the apex. Fig. 29. Transverse section through the same root, separated by the thickness of one section. Fig. 30. Longitudinal section through root. P— plerome. FARMER.- ON ISOETES. Farmer del. Vol. V7Pl.V. University Press, Oxford. Urinals of Bofccny Vol. V,Pl.V. wm A" wm- f University Press, Oxford. Farmer del. mm Vol. V, FI. VI. University Press, Oxford. From Photo? Vol. V, FI. VL ^ss! University Press-, Oxford, . Fucus vesiculosus, Linn. 1-14. f. sphaerocarpa, J. Ag. f. laterifructa, Grev. f. spiralis, Linn. 4 ! 7. 8 ! 9 ! f. baltica, J. Ag. 4 ! 8 ! 9 ! f. nana, Batt. 4. F. serratus, Linn. 1-14. f. latifolia, Turn. 1 ! Ascophyllum Stackh. A. nodosum, Le Jol. ( Fucus nodosus , Phyc. Brit.). 1-14. f. scorpioides, Hauck. 718! A. Mackaii, Holm, et Batt. {Fucus Mackaii , Phyc. Brit.). 1 ! 2. 10. Pelvetia Dene et Thur. P. canaliculata, Dene et Thur. {Fucus canaliculatus , Phyc. Brit.). 1--14. Bifurcaria Stackh. B. tuberculata, Stackh. {Pycnophycus tuberculatus, Phyc. Brit.). 9! 10. 14. Himanthalia Lyngb. H. lorea, Lyngb. 1-14. Halidrys Lyngb. H. siliquosa, Lyngb. 1-14. f. gracilis, Holm, et Batt. 419! Cystoseira C. Ag. C. ericoides, C. Ag. 2 ! 7 ! 9 ! 10. 11. 14. C. granulata, C. Ag. 5 ! 6 ! 9 ! C. discors, C. Ag. ( C.foeniculaceus , Phyc. Brit.). 6 ! 9 ! 10. 11. C. fibrosa, C. Ag. 9! 10. 11. 14. Cohort VL— TILOPTERIDINAE. O rd er. — tilofterid ace ae . Tilopteris Kiitz. T. Mertensii, Kiitz. {Edocarpus Mertensii , Phyc. Brit.). 1-4! 7. 9! 86 Holmes and Batters . — A Revised List of PHAEOPHYCEAE (continued). Cohort VIL— DICTYOTINAE. Order.— DICTYOTACEAE. Dictyota Lamx. D. dichotoma, Lamx. 1-14. f. implexa, J. A g. (D. dichotoma , f, intricata , Phyc. Brit.). 1-14. f. latifrons, Holm, et Batt. 9 ! D. ligulata, J. Ag. 9 ! Taonia J. Ag, T. atomaria, J. Ag. 4 ! 5. 6 ! 8 ! 9 ! 10, 11. f. divaricata, Plolm. et Batt. 9 ! Padina Adans. P. pavonia, Gaillon. 9 ! Dictyopteris Lamx. D. polypodioides, Lamx. (Haliseris polypodioides , Phyc. Brit.). 9! 10. 11. 14. Series IV -RHODOPH YCEAE. Cohort I.— POEPHYRINAE. Order.— PORPHYRACEAE. Goniotrichum Kiitz. Goniotrichum elegans, Le Jol. (Bangia elegant, Phyc. Brit.). 4! 9! 12. Bangia Lyngb. B. fusco-purpurea, Lyngb. 1-14. f. crispa, Holm, et Batt. (Bangia crispa , Holm. Fasc. No. 104). 9 ! f. Lejolisii, Holm, et Batt. 9 ! Erythrotrichia Aresch. E. carnea, J. Ag. (Bangia cera?tiicola, Phyc. Brit.). 1. 2. 4 ! 9! Porphyra C. Ag. P. ciliaris, Crn. (Bangia ciliaris , Phyc. Brit.). 1 ! 7! 9! P. coccinea, J. Ag. 114! §7 the British Marine Algae . RHODOPHYCEAE ( continued) ). Porphyra leucosticta, Thur. 1-9 ! P. linearis, Grev. (P. vulgaris , Phyc. Brit, pro parte). 1-9 ! P. laciniata, C. Ag. 1-14. f. typica. f. umbilicalis. P. amethystea, Kiitz. 4 ! P. abyssicola, Kjellm. 1 ! Diploderma Kjellm. D. miniatum, Kjellm. 1 ! 4 ! 13. D. amplissimum, Kjellm. 13 ! <*■ Cohort II.— NEMALIONINAE. Order. — helminthocladiaceae. Tribe I.— Chantransieae. Chantransia Fries. Ch. Daviesii, Thur. ( Callithamnion Daviesii , Phyc. Brit.). 1-14. Ch. corymbifera, Thur. 9 ! Ch. virgatula, Thur. ( Callithamnion virgatulum , Phyc. Brit.). 1-14. Ch. secundata, Thur. 1-9 ! Ch. luxurians, Thur. 6. 9 ! Tribe II. — Nemalieae. Nemali on Targioni-Tozzetti. N. lubricum, Duby. 619! N. multifidum, J. Ag. 1. 2. 5. 6 ! 9 ! 10. 1 1 ! Helminthoeladia J. Ag. H. purpurea, J. Ag. ( Nemalion purpureum , Phyc. Brit.). 9 ! 11. H. Hudsoni, J. Ag. 9 ! Helminthora J. Ag. H. divaricata, J. Ag. {Dudresnaya divaricata, Phyc. Brit.). 1. 9! 13. 88 Holmes and Batters . — A Revised List of RHODOPHYCEAE (continued). Order II. — chaetabtgiaceae. Tribe. — Scinaieae. Scinaia Bivona. S. furcellata, Bivona ( Ginnania furcellata, Phyc. Brit.) i. 2. 9 ! f. subcostata, J. Ag. i ! Order III.— gelidiaceae. Tribe I.— Binderelleae. Choreocolax Reinscho Ch. Polysiphoniae, Reinsch. 419! Tribe II. — Harveyelleae. Harveyella Schmitz et Rke. H. mirabilis, Schmitz et Rke 419! T ribe 1 1 1. — Wrangelieae, Atractophora Crn. A. hypnoides, Crn. 9 ! Naecaria Endlicher, N. Wigghii, Endlicher. 2. 7. 8 ! 9 ! 10. 11. 13. Tribe IV. — Gelideae. Pterocladia J. Ag. P. capillacea, Bornet ( Gelidium corneum , var. capillaceum, Phyc. Brit.). 9. Gelidium Lamx. G. corneum, Lamx. 1-14, f. abnormis, Grev. f. aculeata, Grev. f. clavata, Grev. f. clavifera, Grev. f. conferta, Grev. f. flexuosa, Harv. f. latifolia, Grev. f. pulchella, Grev. f, sesquipedalis, Grev. f. uniformis, Grev. G. crinale, J. Ag. ( G . corneum , var. critiale , Phyc. Brit.). 1. 4! 5. 9! 89 the British Marine Algae . RHODOPHYCEAE (continued). Cohort III. — GIGARTININAE. Order I.— gigartinaceae. Tribe I.— Gigartineae. Chondrus J. Ag. Ch. crispus, Stackh. 1-14. f. virens, Turn, f. stellata, Turn, f. aequalis, Turn, f. filiformis, Turn, f. patens, Turn, f. sarniensis, Turn. Gigartina Stackh. G. Teedii, Lamx. 9 ! G. acicularis, Lamx. 9 ! 11. 13, G. pistillata, Stackh. 9 ! G. mamillosa, J. Ag. 1-14. f. linearis, Turn, f. prolifera, Turn, f. echinata, Turn, f. incurvata, Turn. Tribe II. — Tylocarpeae. Phyllophora Grev. Ph. rubens, Grev. 1-4 ! 9 ! Ph. Brodiaei, J. Ag. 1.4! 5 ! 7 ! 12. f. angustissima, C. Ag. 1 ! Ph. Traillii, Holm, et Batt. 4 ! 5. 9 ! Ph. palmettoides, J. Ag. 9 ! Ph. membranifolia, J. Ag. 1-14. Stenogramme Harv. S. interrupta, Mont. 9 ! 10. 14! Gymnogongrus Mart. G. Griffithsiae, Mart. 1. 2. 9 ! 10. 12. G. norvegicus, J. Ag. ( Chondrus norvegicus , Phyc. Brit,). 1. 2. 6 ! 7. 9 ! Ahnfeltia Fries. A. plicata, Fries ( Gymnogongrus plicatus , Phyc. Brit,). 1-14, 90 Holmes and Batters . — A Revised List of RHODOPHYCEAE (continued). Actinococcus Kiitz. A. roseus, Kiitz. i. 4! 5 ! 6 ! 7 ! Tribe III. — Callymenieae. Callophyllis Kiitz. C. laciniata, Kiitz. (Rhodymenia laciniata , Phyc. Brit.). 9 ! Gaily menia J. Ag. C. reniformis, J. Ag. 1. 2. 9! 10. 11. 13. C. microphylla, J. Ag. 9 ! Order II. — rhodophyllidaceae. Tribe I. — Cystoclonieae. Cystoclonium Kiitz. C. purpurascens, Kiitz. (Hypnea purpurascens , Phyc. Brit.). 1-14. Catenella Grev. C. Opuntia, Grev. 1--14. Euthora J. Ag. E. cristata, J. Ag. ( Rhodymenia cristata, Phyc. Brit.). 1.417! Tribe II.—Rhodophyllideae. Rhodophyllis Kiitz. Rh. bifida, Kiitz. (Rhodymenia bifida , Phyc. Brit.). 1. 2. 4. 5. 7! 8. 9! 11. 14. f. latifrons, Holm, et Batt. 9 ! Rh. appendiculata, J. Ag. {Rh. bifida , var. ciliata} Phyc. Brit.). 9 ! Cohort IV.— RHODYMENINAE. Order I— sphaerococcaceae. Tribe I. — Sphaerococceae. Sphaerococcus Grev. Sp. coronopifolius, Grev. 2. 6. 9 ! 11. 14. Tribe II.— Gracilarieae. Gracilaria Grev. G. confervoides, Grev. 1-14. 91 the British Marine Algae. RHODOPHYCEAE (continued). Gracilaria divergens, J. Ag. 9 ! G. compressa, Grev. 9 ! G. multipartita, J. Ag. 9. Calliblepharis Kiitz. C. ciliata, Kiitz. (Rhodymenia ciliata , Phyc. Brit.). 1.2. 7 ! 8 ! 9 ! 11. 14. f. angusta, Holm, et Batt. 8 ! C. jubata, Kiitz. (Rhodymenia jubaia, Phyc. Brit.). 1. 2. 7. 9 I M- f. divaricata, Holm, et Batt. 9 ! f. dilatata, Holm, et Batt. 9 ! Order II.— rhodymeniaceae. Tribe I. — Rhodymenieae. Rhodymenia J. Ag. Rh. palmetta, Grev. 1. 2. 5. 6. 9 ! 10. 11. 14, f. Elisiae, Kiitz. 9 ! f. bifida, Turn. 9 ! f. crassiuscula, Turn. 9 ! f. flabelliformis, Kiitz. 9 ! f. divaricata, Kiitz. 9 ! Rh. palmata, Grev. 1-14. f. typica, Kjellm. 419! f. marginifera, Harv. 9 ! f. sarniensis, Grev. 419! f. simplex, J. Ag. 9 ! f. sobolifera, J. Ag. 419! f. laciniata, Holm, et Batt. 419! Rh. nicaeensis, Holm. (R. palmetta , var. nicaeensis} Phyc. Brit.). 6. 8. 9 ! Cordylecladia J. Ag. C. erecta, J. Ag. (Gracilaria erecta , Phyc. Brit.), 416! 9 ! 11. Lomentaria Lyngb. L. articulata, Lyngb. (Chylocladia articulata , Phyc. Brit.). 1-14. 92 Holmes and Batters. — A Revised List of RHODOPHYCEAE (continued). Lomentaria clavellosa, Gaill. ( Chrysymenia clavellosa, Phyc. Brit.). 1-14. L. rosea, Thur. ( Chrysymenia rosea , Phyc. Brit.). 1 ! 41619! Ghampia Lamx. Ch. parvula, Harv. ( Chylocladia parvula , Phyc. Brit.). 1. 4 ! 6. 9 ! Chylocladia Grev. Ch. kaliformis, Grev. 1. 2. 6. 9 ! 10. 11. 14. f. patens, Kiitz. 9 ! f. squarrosa, Harv. 9 ! Ch. ovalis, Hook. 1. 2. 3. 6. 9 ! 10. 11. 14. Ch. reflexa, Lenorm. 9 ! Tribe II.-— Plocamieae. Piocammm Lyngb. PI. coccineum, Lyngb. 1--14. f. angustifrons, Le Jol. 1-14. f. latifrons, Le Jol. 1-14. f. uncinata, C. Ag. 419! Order III.— delesseriaceae. Tribe I.— Nitophylleae. Nitophyllum Grev. N. uncinatum, J. Ag. 1.9! N. Gmelini, Harv. 6! 9 ! n. N. laceratum, Grev. 1-14. f. uncinata, Grev. 9 ! f. Smithii, Kiitz. 419! N. reptans, Crn. 419! N. punctatum, Grev. 1-14. f. ocellata, J. Ag. 1.4! 6. 9 ! f. crispata, Harv. 1.4! 9. f. Pollexfenii, Harv. 1 ! f. fimbriata, Harv. 1.4! 6. 9 ! N. venulosum, Zan. 9. (N thysanorhizans , Holm. Grevillea, 1874, p. 2, pi. 12, and 1875, pi. 37, figs. 5-7). N. Bonnemaisonii, Grev. 1. 3. 4 ! 5. 6. 9 ! f. crassinervis, Batt. 4 ! N. Plilliae, Grev. 4 ! 9 1 14. 93 the British Marine Algae. RHODOPHYCEAE {continued). Nitophyllum literatum, J. Ag. 9 ! N. versicolor, Harv. 1. 6 ! 14. Tribe II. — Delesserieae. Delesseria Lamx. D. alata, Lamx. 1-14. D. angustissima, Griff. 1.3! D. Hypoglossum, Lamx. 1. 2. 4 ! 5. 6. 7 ! 8. 9 ! 10. 11. 14. f. crispa, Crn. 9 ! D. ruscifolia, Lamx. 1. 2. 4 ! 8-9! 10. 11. 14. D. sinuosa, Lamx. 1-14. D. sanguinea, Lamx. 1-14. Order IV. — bonnemaisoniaceae, Bonnemaisonia C. Ag. B. asparagoides, C. Ag. 1-14. f. teres, Harv. * Order V. — rhodomelaceae. Tribe I. — Rhodomeleae. Bostrychia Mont. B. scorpioides, Mont. 4 ! 5. 9 ! 10. ir. 13 ( Helicothamnion scorpioides , Phyc. Brit.). Rhodomela C. Ag. Rh. subfusca, C. Ag. 1-14. f. gracilior, J. Ag. 4 ! Rh. lycopodioides, C. Ag. 1-14. f. typica, Kjellm. 1-14. f. laxa, Kjellm. 1.4! Odonthalia Lyngb. O. dentata, Lyngb. 1. 2. 3. 4 ! 5. 7 ! 10. Tribe II. — Laurencieae. Laurencia Lamx. L. obtusa, Lamx. 1. 2. 4 ! 9 ! 14. f. genuina, Hauck. 9 ! f. crucifera, Hauck. 9 ! L. hybrida, Lenorm. 1-14. L. pinnatifida, Lamx. 1-14. 94 Holmes and Batters . — A Revised List of RHODOPHYCEAE (continued). Tribe III.-— Amansieae. Halopithys Kiitz. H. pinastroides, Kiitz. (Rytiphloea pinastroides, Phyc. Brit.). 5. 9 ! Tribe IV. — Polysiphonieae. Chondria Harv. Ch. tenuissima, C. Ag. (Laurencia tenuissima, Phyc. Brit.). 9! 14. Ch. dasyphylla, C. Ag. (Laurencia dasyphylla , Phyc. Brit.). 1-14. Ch. caerulescens, J. Ag. 9 ! Polysiphonia Grev. a. Oligosiphoniae ecorticatae. P. sertularioides, J. Ag. 419! (Polysiphonia pulvinata , Phyc. Brit.). P. Rhunensis, Bornet. 6 ! 9 !♦ P. foetidissima, Cocks. 9 ! P. fibrata, Harv. 1-14. P. urceolata, Grev. 1-14. f. typica, J. Ag. 1-14. f. patens, J. Ag. 4 ! 9 ! f. formosa, J. Ag. (P.formosa, Phyc. Brit.). 1.4! 9 ! f. comosa, J. Ag. 4 ! P. divaricata, Kiitz. 4. /3. Oligosiphoniae corticatae. P. subulata, J. Ag. f. Griffithsiana, J. Ag. (P. Griffithsiana , Phyc. Brit.). 9. P. Richardsoni, Hook. 2 ! P. spinulosa, Grev. 2 ! f. major (P. Carmichaeliana , Phyc. Brit.). P. elongella, Harv. 1. 2. 5. 6. 9 ! 14. P. elongata, Grev. 1-9! n. 14. f. denudata, J. Ag. 4 ! f. rosea, J. Ag. 9 ! P. violacea, Wyatt. 1. 2. 4 ! 5. 9 ! 14. P. fibrillosa, Grev. 419! 95 the British Marine Algae. RHODOPHYCEAE (continued). y. Polysiphoniae ecorticatae. P. variegata, J. A g. 9 ! P. furcellata, Harv. 9 ! f. forcipata, J. Ag. (P. turgidula , Holm. Fasc. No. 7). 9 ! f. patula, J. Ag. (P . furcellata, Phyc. Brit.). 9 ! P. fastigiata, Grev. 1-14. P. ceramiaeformis, Crn. 9 ! P. simulans, Harv. 9 ! P. atro-rubescens, Grev. 1— 14. P. subulifera, Harv. 2. 9 ! 11 ! 13. P. obscura, J. Ag. 9 ! P. nigrescens, Grev. 1-14. f. affinis, Harv. (P. affinis , Phyc. Brit.), P. parasitica, Grev. 1. 2 ! 4 ! 6. 9 ! 14, P. byssoides, Grev. 9 ! 8. Polysiphoniae coriicatae. P. Brodiaei, Grev. 1-9 ! 11. 14. f. typica, Holm, et Batt. 9 ! f. densa, Holm, et Batt. 9 ! P. thuyoides, Harv. ( Rytiphloea thuyoides, Phyc. Brit.). 4 ! 5. 6 ! 9 ! 11. P. fruticulosa, Spreng. ( Rytiphloea fruticulosa , Phyc. Brit.). 2. 5. 6! 9 ! 11. 14, Pterosiphonia Falk. P. complanata, Schmitz, MS. 9 ! 11. Tribe V. — Dasyeae. Dasya C. Ag. D. venusta, Harv. 9 ! D. arbuscula, C. Ag. 1. 2. 5. 9 ! 11. 14. D. ocellata, Harv. 9 ! 11. 14. D. punicea, C. Ag. 9 ! D. media, Harv. MS. 1 ! D. coccinea, C. Ag. 1-14. f. tenuis, J. Ag. 1! 9! 14. f. patens, J. Ag. (Z). coccinea , f. squarrosa , Phyc. Brit.), D. Cattloviae, Harv. 9. 9 6 Holmes and Batters.— A Revised List of RHODOPHYCEAE (continued). Order IV. — ceramiaceae. Tribe I. — Spermothamnieae. Sphondylothamnion Nag. S. multifidum, Nag. ( Wrangelia multifida , Phyc. Brit.). 2. 6. 9 ! ii. 14. f. pilifera, C. A g. 9 ! Spermothamnion Aresch. S. Turneri, Aresch. ( Callithamnion Turneri, Phyc. Brit.). 1-14. f. intricata, Holm, et Batt. ( Callithamnion intricatum , J. Ag.). f. repens, Le Jol. 2. 6. 4 ! 9 ! S. flabellatum, Bornet. ( Callithamnion strictum , C. Ag.). 4 ! 9 ! Ptilothamnion Thuret. P. pluma, Thur. ( Callithamnion pluma , Phyc. Brit.). 2. 4 ! 6. 9 ! 11. 14. Tribe II. — Griffithsieae. Griffithsia C. Ag. G. corallina, C. Ag. 1-14. G. setacea, C. Ag. 1-14. G. Devoniensis, Harv. 9 ! G. barbata, C. Ag. 9 ! Halurus Ktitz. H. equisetifolius, Ktitz. ( Griffithsia equisetifolia , Phyc. Brit.). 1-14. f. simplicifilum, Harv. {Griffithsia simplicifilum, Phyc. Brit.). 7. 1 1 ! Tribe III. — Monosporeae. Bornetia Thur. B. secundiflora,Thur. {Griffithsia secundiflora, Phyc. Brit.). 9! Monospora Sober. M. pedicellata, Sober. {Callithamnion pedicellatwn, Phyc. Brit.). 1. 2. 5. 6. 9 ! 11. 14. f. comosa, Holm, et Batt. 9 ! M. clavata, J. Ag. 9 ! 97 the British Marine Algae . RHODOPHYCEAE (continued). Pleonosporium Nag. P. Borreri, Nag. {Callithamnion Borreri, , Phyc. Brit.), i. 8. 9 ! 13. f. fasciculata, Holm, et Batt. {Call fascicula/um, Phyc. Brit.). 8! Tribe IV. — Callithamnieae. Rhodochorton Nag \ Rh. Rothii, Nag. ( Callithamnion Rothii , Phyc. Brit.). 1-14. Rh. floridulum, Nag. ( Callithamnion flondulum , Phyc. Brit.). 1-14. Rh. intermedium, Kjellm. 4 ! Rh. mesocarpum, Kjellm. ( Callithamnion mesocarpum , Phyc. Brit.). 2. Rh. membranaceum, Magn. 4 ! 9 l Rh. sparsum, Kjellm. 2. 4 ! 9 ! Callitliamnion Lyngb. a. Eucallithamnion. C. tenuissimum, Kutz. 9 ! C. interruptum, C. Ag. 9 ! C. polyspermum, C. Ag. 1-14. C. roseum, Harv. 1-14, C. tripinnatum, C. Ag. 9. 1 1 . C. affine, Harv. 2. * /3. Phlebolhamnion. C. Hookeri, C. Ag. 1-14. C. Brodiaei, Harv. 4 1 9 ! C. fruticulosum, J. Ag. 9 ! C. arbuscula, Lyngb. 1. 2. 3 ! 4 ! 5. n. C. tetragonum, C. Ag. 1. 2. 5. 6. 9! n. 14. f. brachiata, J. Ag. (C. brachiatum , Phyc. Brit.). 1. 2. 5. 6. 9 ! 11. 14. C. tetricum, C. Ag. 9! n. 14. 1 In the absence of cystocarpic fruit, which is unknown at present, the position of this genus is doubtful j it is placed here only for the sake of convenience. H 98 Holmes and Batters. — A Revised List of RHODOPHYCEAE {continued). y. Poecilothamnion. C. corymbosum, Lyngb. 1-14. C. granulatum, C. A g. (C. spongiosum , Phyc. Brit.). 1-14. d. Seirospora. C. seirospermum, Griff. 1 ! 2. 3. 9 ! f. miniata. 9 ! f. versicolor, Holm, et Batt. 9 ! C. byssoides, Am. 1. 9, 14. f. seirosporifera, Holm, et Batt. ( C . hormocarpum, Holm.). 9. Tribe V. — Compsothamnieae. Compsothamnion Schmitz. C. thuyoides, Schmitz ( Callithamnion thuyoideum, Phyc. Brit.). 6. 8. 9. 11. 14. C. gracillimum, Schmitz ( Callithamnion gracillimum, Phyc. Brit.). 4. 5. 6. 9. Tribe VI. — Ptiloteae. Plumaria Schmitz. P. elegans, Bonnem. 1-14. Ptilota C. Ag. P. plumosa, C. Ag. 1 ! 2. 3. 4 ! 7 ! 10. 1 1. Tribe VII. — Crouanieae. Antithamnion Nag. A. cruciatum, Nag. ( Callithamnion crucialum, Phyc. Brit.). 2 ! 5 ! 6. 9 ! 14. f. pumila, Harv. 9 ! A. plumula, Thur. ( Callithamnion plumula , Phyc. Brit.). 1-14. f. crispa, J. Ag. 419! f. spinescens, Stromf. 4 ! A. floccosum, Kleen. ( Callithamnion floccosum. Phyc. Brit.). 1. 2. 4! A. barbatum, Holm, et Batt. (< Callithamnion barbatum , Phyc. Brit.). 4 ! 6 ! 9 ! Crouania J. Ag. C. attenuata, J. Ag. 9 ! 99 the British Marine Algae . RHODOPHYCEAE (continued). Tribe VIII. — Spyridieae. Spyridia Harv. S. filamentosa, Harv. 6 ! 9 ! Tribe IX. — Ceramieae. Ceramium Lyngb. a. Inermes. C. gracillimum, Harv. 9 ! n. C. fastigiatum, Harv. 4. 9! 11. C. tenuissimum, J. Ag. ( C . nodosum , Phyc. Brit.). 5. 6. 9 ! f. arachnoidea, C. Ag. 9 ! C. Deslongchampsii, Chauv. 1. 2. 4 ! 5. 6. 7. 9! 11. 14. C. strictum, Harv. 4 ! 6. 9! n. f. divaricata, Holm, et Batt. (C. diaphanum , Crn.). 9 ! C. diaphanum, Roth. 419! C. circinatum, J. Ag. ( C . decurrens , Phyc. Brit.). 9 ! C. rubrum, C. Ag. 1-14. f. pedicellata, J. Ag. 419! f. prolifera, J. Ag. (C. botryocarpum , Phyc. Brit.). 419! f. secundata, J. Ag. 419! f. corymbosa, J. Ag. f. microcladioides, Holm, et Batt. ( C . Microcladia, Cocks.). 4 ! 7 ! 9 ! 13. Armatae. C. echionotum, J. Ag. 1.9! C. acanthonotum, Carm. 1-14. f. transcurrens, Holm, et Batt. 9 ! C. ciliatum, Ducluz. 9! 10. n. C. flabelligerum, J. Ag. 4 ! 5. 9 ! Microcladia Grev. M. glandulosa, Grev. 9 ! Cohort V. — CRYPT ONE MIN AE. Order I. — gloeosiphoniaceae. Gloeosiphonia Carm. G. capillaris, Carm. 1. 2. 3. 4 ! 5. 9 ! 11. 14. H 2 ioo Holmes and Batters* — A Revised List of RHODOPHYCEAE (continued). Order II.— grateloupiaceae. Halymenia J. A g. H. ligulata, C. Ag. 2. 3. 6. 8 ! 9 ! n. 13. 14. f. dichotoma, Harv. 9 ! f. latifolia, Harv. 9 ! f. ramentacea, Harv. 9 ! Grateloupia C. Ag. G. filicina, C. Ag. 9 ! f. intermedia, Holm, et Batt. 9 ! G. dichotoma, J. Ag. 9 1 Order III. — dumontiaceae. Dmnontia Lamx. D. filiformis, Grev. 1-14. f. crispata, J. Ag. 419! Dudresnaya Bonnem. D. coccinea, Bonnem. 2. 4! 9! n. Dilsea Stackh. D. edulis, Stackh. (Iridaea edulis> Phyc. Brit.). 1-14. Order IV. — nemastomaceae. Tribe I. — Schizymenieae. Calosiphonia Crn. C. Finisterrae, Crn. 9 ! Sehizymenia J. Ag. S. Dubyi, J. Ag. (. Kallymenia Dubyi ’ Phyc. Brit.). 1. 9! 11. Tribe II.— Halarachnieae. Furcellaria Lamx. F. fastigiata, Lamx. 1-14. Order V. — rhizophyllidaceae. Polyides C. Ag. P. rotundus, Grev. 1-14. Order VI. — squamariaceae. Tribe I. — Cruorieae. Petrocelis J. Ag. P. cruenta, J. Ag. ( Cruoria pellita , Phyc. Brit.). 2. 4 ! 9 ! 11. IOI the British Marine Algae . RHODOPHYCEAE {continued). Petrocelis Hennedyi, Batt. (Actinococcus Hennedyi, Harv.). 2 ! 4 ! 7 ! Cruoria Fries. Cr. pellita, Lyngb. 4! 5. 6. 9! 14. Tribe II. — Squamarieae. Peyssonnelia Dene. P. Dubyi, 1-14. P. Harvey ana, Crn. 4 ! 9 ! GENERA OF DOUBTFUL AFFINITY. Haematoeelis J. A g. H. fissurata, Crn. 4 ! HaematopKlaea Crn. H. Crouanii, Crn. 419! Rhododermis Crn. Rh. elegans, Crn. f. polystromatica, Batt. 419! Rh. parasitica, Batt. 4 1 Order VII. — hildenbrandtiaceae. Hildenbrandtia Nardo. H. prototypus, Nardo. f. rosea, Kiitz. {H. rubra, Phyc. Brit.). 1-14. Order VIII.— corallinaceae, Sehmitziella Born, et Batt. S. endophloea, Born, et Batt. 5 I 9 ! Choreonema Schmitz. Ch. Thuretii, Schmitz {Melobesia Thuretii , Born. ; Holm. Fasc. No. 14). 9 ! Melobesia Lamx. M. confervoides {Lithocystis Allmanni \ Phyc. Brit.). 419! M. corticiformis, Kiitz. 419! M. membranacea, Lamx. 1--14. M. farinosa, Lamx. 4 1 61 9 ! M. vermcata, Lamx. 4 ! 6. 9 ! M. Lejolisii, Rosan. 419! M. pustulata, Lamx. 1-14. H 3 102 Holmes and Batters. — A Revised List of RHODOPHYCEAE {continued). Melobesia macrocarpa, Rosan. 419! M. Laminariae, Crn. 419! M. Corallinae, Crn. 419! Lithophyllnm Phil L. lichenoides, Phil. ( Melobesia lichenoides , Phyc. Brit.). 6 ! 9 ! 14. L. Lenormandi, Rosan. 4 ! 6 ! 9 ! Lithothamnion Phil. L. fasciculatum, Aresch. (Melobesia fasciculata , Phyc. Brit.). 11. L. calcareum, Aresch. (Melobesia calcarea , Phyc. Brit.). 2. 3. 4 ! 6. 9 ! 11. 14. L. polymorphum, Aresch. (Melobesia polymorpha , Phyc. Brit.). 1-14. L. agariciforme, Aresch. (Melobesia agariciformis , Phyc. Brit.). 11. Corallina Lamx. C. officinalis, Linn. 1-14. C. squamata, Ellis. 6 ! 9 ! 14. C. mediterranea, Aresch. 9 ! C. rubens, Ellis et Sol. (Jania rubens , Phyc. Brit.). 6. 9 ! 10. 14. f. corniculata, Hauck. (Jania corniculaia , Phyc. Brit.). 5, 6! 9! 11. 14. the British Marine Algae . 103 APPENDIX I. The following species must be excluded from the list of British Marine Algae, since they have not been proved to grow on the shores of Britain, but have only been met with as waifs. PHAEOPHYCEAE. Cystoseira barbata, C. Ag. Laminaria longicruris, De la Pyl. Sargassum bacciferum, C. Ag. „ vulgare, C. Ag. RHODOPHYCEAE. Dasya Mulleri, Sond. Gelidium cartilagineum, Gaill. APPENDIX II. The following species may be expected to occur on the shores of Britain, having been found either on the Atlantic shores of France, or of Norway, or in the Baltic Sea. It is possible that species belonging to the Mediterranean Flora may also occur, as well as Nitophyllum venulosum , Zan., but it is not possible to suggest with any degree of certainty the species which may occur on the South-west coasts of England and Ireland. The capital letters N. and S. are employed to indicate that they may occur respectively on the Northern or Southern shores of Britain. CYANOPHYCEAE. BrachytricMa Balani, Born, et Flah. S. Calothrix Contarenii, Born, et Flah. N. S. C. fusco-violacea, Crn. S. C. rubra, Born, et Flah. S. Gloeotrichia punctulata, Thur. S. Lyngbya gracilis, Menegh. S. L. membranacea, Kiitz. S. L. persicina, Kiitz. S. 104 Holmes and Batters. — A Revised List of CYANOPHYCEAE ( continued ). Merismopoedia glauca, Naeg. S. Nodularia armorica, Thur. S. Oscillaria subsalsa, C. Ag. N. Plectonema terebrans, Born, et Flah. S. Phormidium incrustatum, Gom. MS. S. Plenrocapsa fuliginosa, Hauck. N. S. Spirulina versicolor, Thur. S. CHLOROPHYCEAE. Acrochaete repens, Pringsh. S. Blastophysa rhizopus, Rke. N. Characium marinum, Kjellm. N. Chaetomorpha Cladophorae, Crn. N. „ gracilis, Kiitz. N. S. „ Sphacelariae, Fosl. N. Chloroehytrium dermatocolax, Rke. N. S. Chlorangimn marinum, Cienk. N. Cladophora pygmaea, Rke. N. „ sericea, Reinb. N. S. Enteromorpha fucicola, J. Ag. N. S. „ radiata, J. Ag. N. S. „ tubulosa, J. Ag. N. S. Monostroma balticum, Wittr. N. „ fuscum, Wittr. N. „ oxycoccum, Kiitz. S. „ orbiculatum, Thur. S. ,, splendens, Wittr. N. Ostreobium Queketti, Bom. et Flah. S. Phaeophila Engleri, Rke. N. „ Floridearum, Hauck. S. Protoderma marinum, Rke. N. Schizogonium laete virens, Kiitz. N. f. crispata, Reinb. Ulvella lens, Crn. S. Vaucheria intermedia, Nordst. N. S. „ coronata, Nordst. N. S. „ piloboloides, Thur. N. S. Zygomitus reticulatus, Born, et Flah. S. the British Marine Algae. PHAEOPHYCEAE. Alaria linearis, Stromf. N. Ascocyclus foecundus, Rke. N. „ globosus, Rke. N. „ ocellatns, Rke. N. Coilodesme bulligera, Stromf. N. Ectocarpus fulvescens, Born. S. „ microscopicus, Crn. S. „ Myriocladiae, Crn. S. „ Stilophorae, Crn. N. S. Desmotrichum balticum, Kiitz. N. „ scopulorum, Rke. N. Fucus evanescens, C. Ag. N. Gobia baltica, Rke. N. Halorhiza vaga, Kiitz. N. Haplospora globosa, Kjellm. N. Kjellmania sorifera, Rke. N. Leptonema fasciculatum, Rke. N. Liebmannia major, Crn. S. Lithoderma fatiscens, Aresch. N. Myriocladia chordariaeformis, Crn, S. „ tomentosa, Crn. S. Phyllaria lorea, Kjellm. N. Seaphospora speciosa, Kjellm. N. Seytosiphon pygmaeus, Rke. N. Streblonema volubilis, Thur. S. Symphoricoccus radians, Rke. N. S. RHODOPHYCEAE. Antithamnion boreale, Kjellm. N. Callithamnion bipinnatum, Crn. S. „ decompositum, J. Ag. S. „ elegans, C. Ag. S. „ fallax, Crn. S. „ Furcellariae, J. Ag. S. „ Gaillonii, Crn. S. „ Hapalidii, Crn. S. „ parvulum, Crn. S. 105 io6 Holmes and Batters . — A Revised List of RHODOPHYCEAE ( continued] ). CaHithamnion serpens, Crn. S. „ sphaericum, Crn. S. Callophyllis flabellata, Crn. S. Ceramium pennatum, Crn. S. Chantransia efflorescens, J. A g. S. Contarinia pulcherrima, Crn. S. Crouania bispora, Crn. S. Cruoriella armorica, Crn. S. Cryptonemia seminervis, J. A g. S. Delesseria Boerii, Rupr. N. Dermocorynus Montagnei, Crn. S. Halosaccion ramentaceum, J. Ag. N. Haematocelis parasitica, Crn. S. „ rubens, J. Ag. S. Liagora viscida, C. Ag. S. Lithophyllum laeve, Stromf. N. Lithothamnion circumspectum, Stromf. N. „ depressum, Crn. N. „ glaciale, Kjellm. N. „ intermedium, Kjellm. N. „ soriferum, Kjellm. N. Melobesia callithamnioides, Rosan. S. „ confinis, Crn. S. „ hapalidioides, Crn. S. „ myriocarpa, Crn. S. „ simulans, Crn. S. Nemastoma marginifera, J. Ag. S. Kitophyllum alliaceum, Crn. S. „ Sandrianum, J. Ag. S. Peyssonnelia atro-purpurea, Crn. S. „ rupestris, Crn. S. Phyllopliora Bangii, Jensen. N. „ Herediae, J. Ag. S. Polysiphonia insignis, Crn. S. „ intricata, J. Ag. S. „ opaca, Zan. S. „ pennata, J. Ag. S. Ptilota pectinata, Kjellm. N. 107 the British Marine Algae. RHODOPHYCEAE (continued). Ptilota serrata, Kiitz. N. Rhodochorton chantransioides, Rke. N. Rhodomela virgata, Kjellm. N. Rhodophyllis dichotoma, Gobi. N. Solieria chordalis, J. A g. S. Is the Eusporangiate or the Leptospor- angiate the more primitive type in the Ferns1? BY F. O. BOWER, Regius Professor of Botany in the University of Glasgow . With Plate VII. IN my paper on 4 The comparative examination of the Meristems of Ferns as a phylogenetic study,’ published in the Annals of Botany, vol. Ill, p. 305, &c., a very consider- able number of facts were passed in review, relating to the embryonic tissues of root, stem, leaf, wing, and sporangium ; the observations were made upon representatives of various divisions of the Filicineous series, viz. the Hymenophyllaceae, Polypodiaceae, Cyatheaceae (in part), Schizaeaceae, Osmunda- ceae, and Marattiaceae. The main result was to show that there is a singular parallelism in character of all the meristems in these several divisions ; it was demonstrated that, in the divisions first named, the meristems of each of the constituent parts of the plant are relatively simple in construction, and exhibit a definite regularity of segmentation, one initial cell (or in the wings a row of initial cells) of definite form being present in each. Passing onwards through the series, this simplicity and regularity is departed from ; the structure be- 1 This question was discussed by the author at the Royal Horticultural Society’s Conference on Ferns, in July, 1890, and a statement of his views then put forward is printed in the Journal of the Society, N. S, vol. XII. pp. 496-505. [Annals of Botany, Vol. V. No. XVIII. April, 1891.] I no Bower . — Is Eusporangiate or Leptosporangiate comes more complex, the identity of the single initial is lost, and the regular sequence of segmentations gives place to a less definite arrangement. On these characters therefore, as well as on these of the mature parts to which the meristems give rise, the Ferns may be arranged as a series : at the one end are the typically more delicate Leptosporangiate Ferns, while at the other would be the typically more robust Eu- sporangiate forms. It was further remarked in the paper above quoted that this parallelism as regards complexity of structure does not appear only in the parts of the sporophyte, but also that it may be traced in the sexual generation : that in the Hymenophyllaceae, which have a peculiarly delicate structure of the sporophyte, the prothallus is frequently fila- mentous, and the* sexual organs freely exposed, while in the more robust Eusporangiate Ferns, such as Marattia or Ophio - glossum , the prothallus is massive, and the sexual organs deeply sunk in its tissue. Accordingly, whether the general character of the sporophyte, or of the gametophyte be con- sidered, the divisions of the Filicineae might be arranged as a series, extending from the typically Leptosporangiate forms on the one hand to the typically Eusporangiate on the other ; the Osmundaceae, and in some respects the Schizaeaceae, also taking an intermediate position, and serving as connecting links between the two extremes. The question whether or not this series is to be regarded as a simple linear sequence, will be discussed later on. The series thus roughly blocked out appears to be a natural one, from the facts that the Filicineae themselves are obviously a natural group, and that the steps from one extreme to the other are gradual and consistent in all the parts. The next question will naturally be, which is the lower and which the upper end of the series ; which is the more primitive, and which the more recent, and derivative type ? It is to the re- consideration of this very important question that I propose to devote the following pages. The opinion currently held by botanists is that the simpler, Leptosporangiate Ferns are the more primitive, and that the Eusporangiate Ferns occupy the more primitive type in the Ferns f 1 1 1 a higher position in the developmental tree : this view I shared when writing, two years ago, the paper above quoted : I there definitely stated, however, that the converse view was capable of defence (p. 374) ; in fact, that the simpler Ferns might be regarded as forms which had degenerated, and owe their more delicate structure to adaptation to life in moist shade : but this view I did not then accept. Subsequently the question has been taken up by D. H. Campbell1, who has argued in favour of the Eusporangiate forms as being primitive rather than derivative : yet, though he has brought forward various points of interest and importance, the whole matter has not been by any means exhausted, and I therefore propose to look into the evidence which may be adduced in support of the two views, and to consider first what basis of evidence there actually is in favour of the view now currently held. Seeing that the broadest lines of progress of evolution have commonly led from the smaller and simpler to the larger and more complex, there has been a general disposition to assume that the simpler terms of any series are the more primitive. This assumption has doubtless affected the views of botanists with regard to the Ferns, and has led to the established opinion that the Hymenophyllaceae, being structurally the simplest, approach the primitive Filicineous type more nearly than other living forms. But a simplification of structure has been recognised in so many cases as following on exposure to certain conditions of life, that the idea of degeneration has be- come a familiar one. We are therefore no longer justified in making the above assumption unless it be supported by a knowledge of the environment past and present, as well as by comparative evidence. For such evidence recourse must be had in the present case to lower rather than to higher forms, and the comparison has been commonly drawn between the Filmy Ferns and the Mosses: notwithstanding the wide differ- ences between them, it has been generally held that of all Vascular plants the Hymenophyllaceae approach most nearly to the Bryophyta. 1 Botanical Gazette, Jan. 1890. 1 1 2 Bower . — Is Eusporangiate or Leptosporangiate It is not my object here to give a complete history of the origin and growth of this opinion : it is however one of long standing. Both Linnaeus and Sprengel placed the Hymeno- phyllaceae at the end of the series of Ferns, while the Mosses immediately followed them : notwithstanding that R. Brown and Sir W. Hooker1 preferred to make them ‘part of the Polypodiaceae, ranking near Davallia and Loxsoma / Presl2 and Bernhardi separated them as a special family of Ferns, and the former writer concludes that the Hymenophyllaceae are rather far removed from the Filicineae, and must be re- garded as a connecting link with the Mosses and Liverworts 3. Van den Bosch4 went so far as to erect them into an order, which he styled the Bryopterideae, and placed them between Mosses and Ferns. These views were however based chiefly on the external characters of the Sporophyte ; when the in- ternal structure of the Sporophyte as well as the characters of the prothallus had been investigated by Mettenius, he con- cluded 5 that the views of Van den Bosch were untenable, and that though the Hymenophyllaceae occupy the lowest position among the Ferns, being furthest removed from the Ophio- glossaceae, still they are true Ferns. The affinity to the Bryophyta which he also recognised 6, was accepted by Prantl 7, but it remained for Goebel 8 to bring together evidence from the comparative examination of the sexual generation, in support of the Bryophytic affinity. Goebel re- marks at the close of his memoir that we are able even now to follow, at least in part, the phylogenetic development of the sexual generation from the Bryophyta to the Pteridophyta, though the neutral generation fails to supply us with any 1 Genera Filicum, description of Plate XXXI. 2 K. B. Presl, Hymenophyllaceae, 1842, pp. 96, 97. 3 1. c., p. 98. 4 Versl. en Mededeel. d. k. Akad. Amsterdam, XI, 1861, and Journ. d, Bot Nederland., I, 1861. 6 Ueber die Hymenophyllaceae, Abh. Sachs. Ges. d. Wiss. 1864, p. 500. 6 He points out especially the affinity with the Sphagnaceae. 7 Hymenophyllaceae, p. 62, 1875. 8 Zur Keimungsgeschichte einiger Fame, Ann. d. Jardin Bot. de Buitenzorg, vol. VII. the more primitive type in the Ferns ? 1 1 3 suggestion as to the origin of the Fern from the Moss-sporo- gonium. The above brief statement will serve to show how long and how consistently the opinion has been held by special writers upon the Hymenophyllaceae, that they are the most primitive types of living Ferns. We will now consider wherein the points of similarity between them and the Mosses really lie, and try to estimate them at their true value in sup- port of the primitive character of the Filmy Ferns. Over and above the corresponding facts of alternation in the Mosses and Filmy Ferns, and the homosporous charac- ter which they both share, the chief points of similarity are these : — (i) The filmy character of the leaf ; (ii) The filamentous prothallus ; (iii) The projecting sexual organs ; (iv) The presence of a single, well-defined apical cell ; (v) The reputed absence of roots in some Filmy Ferns. Each of these will be successively discussed and criticised. (i) It was perhaps the filmy texture in the leaf more than any other character, which suggested the affinity of the Filmy Ferns to the Bryophyta : long before the phenomena of anti- thetic alternation 1 were properly apprehended, it was pointed out that a similarity of structure exists between the fronds of the Hymenophyllaceae and the leaves of the Mosses, since in both cases the filmy leaf may consist of only a single layer of cells. But while such a comparison was not unnatural some fifty years ago, it is to be borne in mind that the facts of antithetic alternation are now clearly before us 1 : that we are comparing the filmy leaf of these Ferns, which is part of the sporophyte, with the so-called leaf of the Moss, which is part of the gametophyte : the two are not strictly homologous parts, and accordingly their comparison cannot be accepted as convincing : at best we have here only an analogy, the leaf of the Fern not being the lineal descendant of the leaf of the 1 In case this term be unfamiliar, reference may be made to an article ‘ On antithetic as distinct, from homologous alternation of generations in Plants,’ Annals of Botany, vol. IV, p. 347. 1 14 Bower . — Is Eusporangiate or Leptosporangiate Moss. But there are still further reasons for thinking this comparison unsatisfactory. I have attempted elsewhere to show that the £ filmy ’ texture of the leaf is not a safe indi- cation of close affinity even among the Ferns 1, by pointing out that within the Filicineous series it occurs at three distinct points, viz. among the Hymenophyllaceae, the Aspleniums, and the Todeas : if within the very natural group of the Ferns themselves it is not a certain index of affinity, but is rather to be viewed as a result of direct adaptation, how can the filmy texture of the leaf be held to strengthen the comparison be- tween the Hymenophyllaceae and the systematically far distant series of the Mosses ? If the affinity be a true one, the evidence of it must be based on firmer ground than that of the filmy leaf2. (ii) The existence of a filamentous, protonema-like prothal- lus in the Hymenophyllaceae, affords what is apparently a better ground for comparison. Various writers have recog- nised its counterpart in the protonema of the Moss, but none has treated the matter so fully as Goebel, who has made a comparative study of the sexual generation of certain Ferns, and based upon it views as to the phylogeny of Mosses and Ferns, and the relationship between them : he sums up in the following words 3 : ‘We may accordingly regard as the starting- point of the Bryophyta and Pteridophyta, Alga-like forms, consisting of branched filaments, of which the female sexual organs produced on fertilisation the asexual generation. Even now we can partially trace ...... the phylogenetic develop- ment of the sexual generation, or at least form for ourselves a connected idea of it. Still it is not to be forgotten that besides the onward progress from the simple condition of 1 Annals of Botany, vol. Ill, p. 379. 3 Giesenhagen (Flora, Oct. 1890, p. 460) has cited the case of Selaginella euspidata as having at the margins of the leaf a texture similar to that of the Hymenophyllaceae, also Lycopodium linifolium , which is a shade-loving species. He concludes (p. 462) that the simplest Hymenophyllaceae were derived from forms of more complex construction, and are the result of progressive simplifi- cation of morphological structure : also that the Hymenophyllaceae are as near to the Polypodiaceae as any other family of homosporous Leptosporangiates. 8 1. c., p. 1 15. the more primitive type in the Ferns ? 1 1 5 a branched filament, there may have been also a degeneration of the sexual generation, as seems to me probable in the case of the Fern-prothalli even at the present day/ It is further added in a note that ‘the degeneration is in many cases brought about by the transfer of the formation of sexual organs to earlier periods of development of the prothallus.’ That there is a similarity between the protonema of the Moss and the prothallus of the Hymenophyllaceae no one can doubt ; but before it could be finally accepted that the filamentous form is in both families really a primitive charac- ter, and not a result of more direct adaptation to similar external circumstances, which took place independently in the two families, we should require more evidence as to the details of descent than is as yet forthcoming, and the conclusion will need to harmonise with other facts relating to form and de- velopment of these and other organisms. I am not prepared at present to concede this point without considering carefully the grounds on which the opinion is founded. To this end we may first take up the question whether the filamentous form was the original one for the sexual generation of the Bryo- phyta : and secondly, we may inquire whether the similarity of form between the protonema of the Mosses and the fila- mentous prothallus of the Filmy Ferns is an indication of real affinity. Having shown that among the Mosses there are forms in which the leafy plant is of very small size, and simple struc- ture as compared with most Mosses, so that the protonema constitutes the greater part of the sexual generation, Goebel states that ‘ the appearance of a protonema on the germination of spores of the Mosses cannot be regarded as a “ phenomenon of adaptation,” but as a peculiarity inherited from their an- cestors V This conclusion follows from the recapitulation- theory2, which, however, is a much less safe guide in the embryology of plants than in that of animals. I have else- where expressed at length my doubts of the propriety of basing broad phylogenetic conclusions upon details of external 1 1. c., p. 1 1 2. 2 Goebel, Muscineen: Schenks Handbuch, II, p. 387. 1 1 6 Bower,— Is Eusporcmgiate or Leptosporangiate conformation of the sexual generation, in view of the extent of the direct impress of external circumstances upon it in certain known examples 1 : at the same time I am free to admit that a reasonable case (though not a demonstration) can be made out for the relatively primitive character of the Moss-protonema, notwithstanding that the formation of a pro- tonema is not a constant phenomenon in all Mosses 2. Passing to the second question, viz., whether the similarity of form between the protonema of the Moss and the fila- mentous prothallus of the Hymenophyllaceae is an indica- tion of real affinity, we enter on different ground. Between the Mosses and the Ferns there is a very wide gap. Though the general facts of alternation are similar, still as regards the form and structure of the sporophyte the two families have virtually nothing in common ; but in the general conformation of the prothallus, and in its propagation by gemmae, they are alike : can this be accepted as an index of affinity in face of so fundamental a difference in the neutral generation ? Among the higher plants it is notorious how little attention is paid to similarities of external conformation of the vegetative organs if the other characters indicate strong divergence, and there is no reason why this principle should be neglected in dealing with the Cryptogams. Moreover in the protonematoid growths of the Hymenophyllaceae we see an excessively in- constant character : even within the genus Trichomanes , while the prothallus of T. pyxidiferum is throughout filamentous, with exception of the archegoniophores, that of T. alatum is most diverse in its form 3 : in Hymenophyllum on the other hand the flattened form is prevalent : thus within the Hymenophyllaceae there is great want of constancy in that very character to which, in accordance with current views, so much importance is attached as evidence of relationship to the Mosses. This is in itself sufficient to cast doubt upon it, 1 Annals of Botany, vol. I, p. 292. 3 Andreaea is an exception. See Berggren, Studien ofver Mossornas bygnad och Utveckling (Lunds Univ. Arsskrift. T. VII). 3 See Annals of Botany, vol. I, Plates XIV, XV. the more primitive type in the Ferns ? 1 1 7 a doubt which is strengthened by the absence of other evi- dence. It is by no means an improbable view that the filamentous form of the Hymenophyllaceous prothallus is the result of adaptation to the very moist situations in which they commonly grow : an extreme case in fact of that lengthening of the germinal filament which may be produced by certain external conditions 1, and that we have here to deal with a phenomenon of analogy with the Mosses rather than with an index of true affinity ; to this I shall return later. (iii) It will doubtless be remarked, however, that in the freely exposed, projecting sexual organs of the Hymeno- phyllaceae, and especially of Trichomanes, there is an obvious character which is shared with the Mosses : that is so, but the correspondence applies rather to the position of the organs, than to details of their structure. The archegonium is a typi- cal Fern-archegonium : it developes as a Fern-archegonium, and has the single neck-cell, common to Leptosporangiate Ferns2. The antheridia are borne, it is true, on a narrow pedicel, but their development and mature structure conform approximately to that in other Ferns. It is then their position which would provide ground for comparison rather than their structure ; but this protruding position is a necessary result of the simple structure of the prothallus, and if that be a result of relatively direct adaptation, as above suggested, so also would be the exposed position of the sexual organs. (iv) The presence of a single initial cell with definite seg- mentation at the apex of the young Moss-sporogonium, and also at the apex of the stem, leaf, and root of the Lepto- sporangiate Ferns, while such are absent or less definite in their segmentation in the Eusporangiate Ferns, is certainly a fact worthy of note. The common presence of a single initial in the lower forms, and the absence of it from most Phanerogams, may be regarded as pointing towards the con- clusion that those organisms which show the single initial are lower in the scale. Examples are however known of the 1 See Goebel, 1. c., p. 1 15 : also Dodel-Port, Kosmos, 1880, p. 1 1. 3 Annals of Botany, vol. I, p. 210. 1 1 8 Bower— Is Eusporangiate or Leptosporangiate existence of a single initial cell in Phanerogams1, while in certain Thallophytes and Bryophytes no single initial is pre- sent : this point cannot therefore be accepted as having much weight. The presence of a single initial seems frequently to follow a less robust habit and a sharp curvature of surface of the growing-point. Plants of aquatic position are commonly of delicate texture ; most of the lower forms are more or less distinctively aquatic ; accordingly the presence of a single initial, though common in the lower forms, is not necessarily to be viewed as an indication of a lower affinity. (v) Again, some may see in the rootless condition of certain of the Hymenophyllaceae, evidence that these are primitive forms, which share this character with the sporophyte of the Mosses. This condition is reputed to occur in certain species of Trichomanes , but, as Giesenhagen has observed 2, we are not yet in a position to state that these Ferns are really rootless in every stage, and in those species in which the seedlings have been seen, a root is present. But even if they were proved to be actually rootless at all stages of their life, the absence of roots might be a result of degeneration, as it undoubtedly is in Wolffia, or in the Utricularias described by Goebel3 : it is not necessarily to be accepted as a primitive character. We have now reviewed those characters upon which the Bryophytic affinity of the Filmy Ferns may be based, and the most satisfactory character for purposes of comparison is the protonema. Against this, which as above pointed out, may be viewed as a more directly adaptive rather than as an ancestral character, is to be set the fact that the simpler Ferns are the only Leptosporangiate Vascular Cryptogams, and that living forms afford no clue as to any direct mode of origin of such simple sporangia4. Thus the comparison above dis- 1 The most prominent example is the root of Heleocharis palustris. 2 Flora, Oct 1890, p. 460. 3 Ann. d. Jard. Bot. de Buitenzorg, vol. IX, p. 98. 4 It is not necessary to dwell upon Prantl’s suggestion as to the origin of the Hymenophyllaceous sorus from some form like Anthoceros. A view which depends upon the conversion of the internal sporogenous layer into a number of superficial sporangia, without any evidence how such a conversion did or the more primitive type in the Ferns f 1 1 9 cussed appears to rest on very slender grounds, and it may well be asked whether some alternative opinion may not be more probable. May we not find a more true affinity to the lower forms in the Eusporangiate Ferns? In discussing this question I propose to take a general survey of the supposed affinity. In view of the wide differences between the Bryo- phyta and the Pteridophyta, and of the great antiquity of the Ferns, it will not be desirable to compare directly any one living Filicineous type with any one living type of Bryophyte, but rather I would consider the more general question of pro- bability of the Eusporangiate character being primitive and ancestral as compared with the Leptosporangiate. It may be noted, however, that on general comparative grounds the affinity of the Eusporangiate ferns would be to the Liverworts rather than to the Mosses, and the question may therefore resolve itself into this : whether the affinity of the Lepto- sporangiate Ferns to the Mosses, or of the Eusporangiate Ferns to the Liverworts, be the more true and natural one. Looking at the question then in its broader aspect, it will be noted that of the three great phyla of Vascular Crypto- gams, two are exclusively Eusporangiate. There is no evidence, either from present or fossil forms, that the Lycopo- dinae or Equisetineae have had any Leptosporangiate ancestry, and they therefore serve to show that a stock may be Euspor- angiate from the first, and make it also the less probable that the Ferns should have originated otherwise. The absence of any intermediate steps leading to the Leptosporangiate type, except from the Eusporangiate Ferns themselves, adds weight to this argument. In the second place, the more bulky type of sporangium is already foreshadowed by the capsule of the Liverworts ; it would be going too far to say that the capsule of a J linger- mannia or of a Mar chan tia is one Eusporangiate sporangium, for it is probable that in the evolution of the Ferns a sub- could come about, will hardly commend itself to the reason as in any way probable. Moreover, it is not apparent on other grounds that there is any near affinity between the Anthoceroteae, and the Filmy Ferns. See Prantl, Hymenophyllaceae, p. 62. 120 Bower.— Is Eusporangiate or Leptosporangiate division of the archesporium took place, not its mere repetition ; but the resemblance is undeniable : there is thus in the sporo- gonium itself an indication of how the Eusporangiate sporan- gium may have been derived, however vague and uncertain that indication may be thought to be ; whereas there is as yet no rational suggestion as to the mode of origin from the Bryophyta of the sporangium as it is seen in the Lepto- sporangiate Ferns. Passing on to the apical meristems, the characters of these have been used by me as a basis for disposing the Filicineae in series, as above stated. It is to be remembered that such evidence cannot be expected to apply with equal force in all cases, and that it is of greater weight within narrow circles of affinity, than in the comparison of more remotely related organisms. It is, however, worthy of note that while a single initial is present in the young sporogonium of the Moss, in the Liverworts a single initial is not found, though in certain of the Jungermannieae four cells, which hold a central position at the apex of the sporogonium, suggest in some measure that structure which is characteristic of the meristems of the Ma- rattiaceae : it would however be unwise to rest strongly on such a point as this. In comparing the Hymenophyllaceae with the Mosses the mere vegetative characters of the gametophyte have been brought forward as weighty evidence : if we are to depart so far from the methods of classification applied to the higher plants, and consider vegetative characters in plants widely diverse in other respects, as much might I think be said for the similarity between, for instance, the prothallus of the Marattiaceae or Osmundaceae and the sexual plant of the Anthoceroteae : the flattened but massive green thallus, which may in either be branched, is not dissimilar in the two cases. The point of distribution of the sexual organs may appear to be an obstacle, they being on the upper surface in the An- thoceroteae, while in the Marattiaceous prothallus they are commonly on the lower; but Jonkman1 specially states and 1 La generation sexuee des Ma!rattiacees, pp. 13-17. Figs. 53-57. I 2 I the more primitive type in the Ferns f figures the fact that in these plants, both antheridia and archegonia are found on both surfaces, though they are more numerous on the lower. As regards the sexual organs themselves there is a nearer correspondence between the Eusporangiate Ferns and the Liverworts than is to be found between the Leptosporangiate Ferns and the Mosses. I have elsewhere pointed out1 that in the Eusporangiate Ferns the sexual organs are deeply sunk in the tissue of the massive prothallus, a position sufficiently distinct from that of the freely exposed and projecting organs of the Hymenophyllaceae. The same is the case with certain of the Thalloid Liverworts, and especially in the Anthocero- teae. D. Campbell2 has drawn attention to the fact, de- monstrated by Jonkman, that more than a single canal-cell is present in the archegonium of the Marattiaceae, a character in which, according to our present knowledge, they alone among the Vascular Cryptogams compare with the Bryo- phyta : it may also be noted that the embryo of Marattia assumes a vertical position of the axis from the first, accord- ing to Luerssen3; but this is a point to which too much importance should not be attached. Do what we will by drawing comparisons based on such points as these, the difference between any living Fern and any living Bryophyte is an uncommonly wide one, and it is almost useless to at- tempt to place any view of relationship upon a sound basis by comparison of mere details in organisms so widely dif- ferent. There is however a line of evidence which, though in itself not conclusive, will serve to give greater stability to the sug- gestion that the Eusporangiate Ferns are the more primitive type : I mean the evidence from Palaeophytology : in ap- proaching the discussion of such a question as the present, too little attention has been paid to this branch. It is hardly necessary to premise that as negative evidence it is not strong : the fact that certain types of plants have not been 1 Annals of Botany, vol. Ill, p. 370. 2 Botanical Gazette, 1890, p. 4. 3 Handbuch d. Syst. Bot., I. p. 582, and Fig. 154. 122 Bower.— Is Eusporangiate or Leptosporangiate found in the earlier rocks does not necessarily prove their absence at the periods when those rocks were formed, though the fact is worthy of note : for our purpose the prevalence of certain forms over others in the earlier formations will com- mand greater attention, and we may at once proceed to consider how, in this respect, the facts of palaeophytology bear upon the present question. Recent writers have repeatedly remarked the preponder- ance of Ferns of the Eusporangiate type in the primary rocks : though very many Fern-remains are represented only by barren fronds, where the sporangia have been found they are in the overwhelming majority of cases of a character allied to the Marattiaceae : it may further be stated that no drawing from a microscopic section showing internal details of an un- doubted leptosporangiate sporangium from the primary rocks has yet been published 1, and it is from these, rather than from mere surface observations of prints, that the most trustworthy evidence is to be gathered. Perhaps the best authenticated example of a print of a Leptosporangiate Fern from the primary rocks is that of Hymenophyllites delicatulus , described and figured by Zeille2, and referred by him to the Hymeno- phyllaceae : here the details of the impression were so well preserved that Zeiller was able to recognise and draw the oblique annulus, which corresponds very closely with that of a modern Filmy Fern. The original specimens of this fossil were examined by Graf zu Solms-Laubach, and from them he concluded ‘that the fact is correctly stated, and that no other interpretation of the figures is possible V The spor- angia figured and described by Mr. Carruthers as being found in a section of a nodule from the coal must also be con- sidered 4. I have had the opportunity, through the kindness 1 Renault states that he has specimens of sporangia of Gleicheniaceae and of Trichomanes in silicified sections from Grand-Croix, but did not publish them because he did not know to what fronds they belonged : Cours de Bot. foss. III. p. 218. The case of sporangia from a coal nodule figured and described by Mr. Carruthers, Geol. Mag., vol. IX, No. 2, 1872 (Plate II, Fig. 5), will be referred to below. 2 Ann. d. Sci. Nat., 6 Serie Botanique, vol. XVI, 1883. 3 Palaeophytologie, p. 157. 4 Geol. Mag. vol. IX, No. 2, PI, II, Fig. 5.. the more primitive type in the Ferns f 123 of Mr. Carruthers, of seeing the original specimen, and there certainly appears to be an oblique annulus, similar to that of the Hymenophyllaceae : it is however to be noted, as indeed Mr. Carruthers himself remarks, that these sporangia are larger than those of present Filmy Ferns, while the stalk appears to be a relatively short and massive one: these points make the further elucidation of the nature of such sporangia very desirable, while in my opinion they raise a doubt as to the near correspondence of this Carboniferous Fern with our present Hymenophyllaceae. The case of Hy - menophyllites Weissii , Sch., figured by Schimper, from the coal of Saarbriicken is much less satisfactory1, the reference of this to the Hymenophyllaceae depending chiefly upon the character of the sorus as a whole (if indeed that which is so described be really a sorus), while the sporangia themselves have not been distinguished or described in detail. The large and typical Devonian Fern, Palaeopteris hibernica , Schimper, (Archaeopteris hibernica, Forbes) has also been referred to the Hymenophyllaceae2: here again it is the character of the sorus as a whole, not of the sporangium, which has led to the conclusion : the sporangia themselves seem not to have yet been seen, and therefore the reference to the Hymenophylla- ceae cannot be taken as more than a provisional suggestion3. Mr. Kidston, after a careful re-examination of the specimens of this species in the British Museum, and in Dublin, comes to the very divergent conclusion that ‘ the true position of Archaeopteris hibernica is in the Marattiaceae/ I have also examined specimens in the British Museum, and failed to recognise any distinct evidence of the Hymenophyllaceous affinity. Stur in speaking of those Carboniferous Ferns which he refers to the Polypodiaceae, regards their position in that 1 Compare Schimper, Traite d. Paleophytologie, PI. XXVIII. 2 Schimper, Traite, PL XXXVI ; Carruthers, Geol. Mag., IX, 1872, p. 3 and Plate II. 3 See also Kidston, on the fructification and affinities of Archaeopteris hibernica ; Forbes, Ann. and Mag. of Nat. Hist. 1888. 124 Bower.— Is Eusporangiate or Leptosporangiate family as no more than a provisional suggestion : he is careful to state1 that in none of these has the sporangium itself been seen, but at most the indusium of the sorus, or the receptacle without sporangia. Passing on to specimens of the carboniferous period, where the microscopic details can be seen in sections, evidence is found of the structure of the sporangia being more complex than that of the Leptosporangiate Ferns. This is the case in the sporangia figured by Williamson2, for in these, traces of a second series of cells are found within the external layer of the wall, a character which is absent in the mature Leptosporangiate sporangium. Prof. Williamson has, with great liberality, shown me those of his sections of coal nodules which exhibit Fern sporangia, and the comparatively small number of these shows how rarely they are preserved. I was struck in looking over these specimens by their great uniformity of type, and have selected a few for detailed drawing (Figs. 1-4). In examining these it is to be borne in mind that the sections pass in irregular directions through the sporangia, but still the similarity is unmistakeable : in each case the superficial layer of cells has thickened and firm cell- walls, but the individual cells are of very irregular size and shape ; no definite ring-like annulus can be traced. Within the outer layer are to be found in each case more or less distinct traces of internal cells (z, z), which do not constitute a regular and continuous layer, but only a partial internal sheath ; at some points a simple line may be seen (as in Fig. 4. x), without any distinct layer of cells ; this will be referred to subsequently. The number of spores in the single sporangium is relatively large, as may be judged from the sporangium shown in Fig. 4, where more than seventy are seen in the single section, and the total number in the sporangium must have been much larger. None of the sections show clearly the mode of insertion, and the sporangia 1 Stur, Die Carbonflora, 1885, p. 235. 2 Phil. Trans., vol. 167, Part I, on the organization of the Fossil Plants of the Coal Measures, Part VIII, PI. 7, Figs. 25-30. the more primitive type in the Ferns? 125 are commonly found quite isolated. I think it probable that these sporangia are similar to those represented by Mr. Kidston, and described by him as ‘ annulate sporangia 1 ; ’ though possibly not specifically identical with sporangia represented in my figures, and though the internal cells are not represented in Mr. Kidston’s figures, still the corre- spondence of his sporangia to those examined by myself is certainly closer than to sporangia of Leptosporangiate Ferns. In searching among modern Ferns for sporangia structurally similar to these from the coal, I have found in Todea barbara a very remarkable resemblance : the main structural points of the Osmundaceous sporangium are already well known : their large size, and short stalk, the absence of a definite ring- like annulus, and dehiscence by a longitudinal slit. In longitudinal section the structure in Todea barbara is as in Fig. 6 : the most noteworthy characters for our present purpose are the irregularity of the external layer of cells, which is composed of relatively large, thick- walled cells at (a), while elsewhere the cells may be relatively small and thin- walled. Within this, and especially towards the base of the sporangium, will be seen small and compressed cells, limited by oblique walls, which remain till the sporangium is mature, constituting a partial and irregular inner layer (i, Figs. 6-8), while, in sporangia not quite mature, a granular film may be traced lining the cavity in which the spores are produced. The stalk of this large sporangium is relatively thin, and appears in the longitudinal section as composed of about four rows of cells. The whole construction of the sporangium is of a more bulky type than that of the typical Leptosporan- giatae, and I have elsewhere shown that this is its character from the very first stages of its development. In comparing this with the fossil sporangia, it is to be remembered that the 1 Trans. Geol. Soc. of Glasgow, vol. IX, Part I, Figs. 11-13. In connection with Mr. Kidston’s use of the words ‘ annulate ’ and ‘ ex-annulate,’ it should be remarked that these terms are not to be taken as substitutes for ‘ Leptosporangiate ’ and ‘ Eusporangiate.’ The fact that an annulus is absent from the Hydropterideae, though these are typically Leptosporangiate forms, shows that precision is necessary on this point. K 126 Bower . — Is Eusporangiate or Leptosporangiate latter are cut through in most irregular directions, and accordingly the comparison should be with irregular and oblique sections from the modern Fern : two such are repre- sented in Figs. 7 and 8, and the similarity, even in details, between these and the sporangia from the coal is very notable : the comparison should specially be made with Fig. 3, and it will be seen that the position and appearance of the e annulus’ (a), the line of dehiscence (d), and the internal cells (z), as well as the relative size and appearance of the rest of the tissues shown, correspond to an extra- ordinary degree. Perhaps the most striking point is that the granular film (x), already noted in the modern sporangium, may be traced in the sporangium from the coal, for the delicate irregular line (x) in Fig. 4 is believed to represent that similarly marked in Figs. 6-8. It is thus seen that the correspondence between the structure of these sporangia from the coal nodules, and of the modern Todea barbara , is an unusually close one. In interpreting this extraordinary resemblance it is to be remembered that these sporangia from the coal nodules are isolated from the fronds ; there is thus no proof from what type of Fern they were derived, other than that yielded by their form and internal structure : it is not even suggested that they all belong to the same species or genus, and I would be far from urging on the above grounds that Todea barbara itself is a plant of very early date : it seems, however, that their Osmundaceous character is probable, and it is to be noted that the Osmundaceae have hitherto been believed to be of post-carboniferous origin. For the purposes of the present argument, these sporangia have an interest : they are clearly not Leptosporangiate, as the word is ordinarily under- stood, but occupy an intermediate position, connecting these with the Eusporangiatae ; their size, their more complex structure, and the number of spores which they produce, all show this ; and as this, though itself rare, is the pro- minent type of Fern sporangium from the coal nodules, of which the microscopic structure is known, we may see in 127 the more primitive type in the Ferns ? that fact a measure of farther evidence of the prevalence of Ferns with a more bulky sporangium in the earlier rocks over those of the true Leptosporangiate type. From the above data the conclusion may be drawn that though it is not possible absolutely to deny the presence of Leptosporangiate Ferns in the primary rocks, still the evidences of their occurrence are at least exceedingly rare, and the question whether they existed at all in those early times is not even yet placed beyond the possibility of doubt by observation of microscopic sections r. But, as above remarked, it is not the present object to prove their absence, but to fully appreciate their rarity in the primary rocks, as compared with the Eusporangiate forms. On this point Stur2 has put forward figures relating to the Car- boniferous Ferns ; in considering which it is to be remembered that many of the Ferns quoted are classified by their vegetative organs alone, and not by observation of their sporangia : his results may be tabulated as follows : — Present Flora. Carboniferous. Ophioglossaceae j 1 genera | species 3 2 l9 Marattiaceae j 1 genera [species 4 23 15 98 Polypodiaceae (?) | j genera [ species 00 0 0 0 C* 4 or 5 58 In estimating the value of these figures it must be remarked that our knowledge of the present Flora is 1 Schenk, in his Handbuch (vol. IV, p. 37), writes of the Hymenophyllaceae, * one observation due to Zeiller is the only evidence of the existence of this family in the older formations;’ and again, speaking of other Leptosporangiate Ferns, ‘ they seem to be entirely absent from the older formations, and to appear first in the Mesozoic strata.’ 2 Die Carbonflora, Abh. d. k. k. Geol. Reichsanstalt zu Wien, 1885, p. 41 1. K 2 128 Bower.— Is Eusporangiate or Leptosporangiate infinitely more perfect than of the carboniferous plants, and that of the fossil Ferns here entered among the Poly- podiaceae, the details of the sporangia are not known in any one case. Bearing these points in mind, it appears that the Ophioglossaceae stand roughly in the present as in the past, that the Marattiaceae of the coal preponderated greatly over those of the present era, both in genera and species, while the Polypodiaceae, which are the most typical Ferns of the present time, are represented in the coal by relatively few forms which are only doubtfully referred to this family. Stur further states that the Gleicheniaceae, Osmundaceae, and Schizaeaceae were entirely absent from the coal, and suggests for them a post-carboniferous origin ; though I do not consider that, in the absence of all know- ledge of their vegetative organs, the sporangia above described demonstrate beyond doubt the presence of Os- mundaceous Ferns in the coal, I should not be prepared to maintain their absence in view of those facts. Speaking generally, the present Eusporangiate Ferns may be said to be the reduced remnants of a more prevalent race of former times, while the Leptosporangiates were in the main a race of later origin, and are now greatly more prevalent than in earlier periods. In the previous pages I have attempted to show that the comparison of the facts of structure and development of present living forms is not incompatible with the view that the Eusporangiates represent the more primitive type for the Filicineae : the palaeophy- tological evidence is clearly in favour of this, though it is not, and cannot be expected to be, absolutely conclusive. In the memoir already referred to at the opening of this paper 1 I have dwelt at some length upon the adaptive nature of the differences of bulk of the various parts of the sporophyte and gametophyte in the Ferns : having demonstrated that, as regards bulk of the young parts, the Ferns form a series, it was recognised that the more robust Eusporangiate forms are better suited in all their parts to 1 Annals of Botany, vol. Ill, pp. 366-374. the more primitive type in the Ferns ? T29 an exposed habitat, while the more delicate Leptosporangiate Ferns are less fitted to withstand exposure in dry air1. On grounds of comparison, which I now am disposed to think were insufficient, I then concluded that the series from the Hymenophyllaceae to the Marattiaceae represents an ascending series, illustrating the emergence of one phylum of the Vascular Cryptogams from the semi-aquatic to the aerial habit2. But, it may well be asked, have we not in the Leptosporangiate Ferns a peculiarly specialised type? They are found at the present day chiefly, and the Hymeno- phyllaceae, upon which the comparison with the mosses is specially based, almost exclusively, under the shade of larger growths3. Where in the earlier period would such shade be found? If, as I have elsewhere suggested4, the origin and differentiation of the spore-bearing generation may be correlated with the migration from water to the land, it would be contrary to all reason to suppose that the primeval forms were such as we now see specialised to life under dense shade. Moreover, the plants which constituted the chief terrestrial growths of the primary rocks were not distinctively shade-giving plants, such as the more modern Angiosperms, under the shadow of which such plants now grow : there is thus a presumption against specialised, shade-loving forms such as the Hymenophyllaceae being really primitive. I am now disposed, on considering all the evidence, to hold that the Leptosporangiate Ferns are derivative and specialised forms, while the Eusporangiatae represent the more primitive type : that the similarities of the vegetative organs, such as they are, between the Mosses and the Hymenophyllaceae are the result of specialisation along two distinct, but parallel, developmental lines, in accordance with similar external con- 1 On the extreme susceptibility of the Hymenophyllaceae to exposure, and their special adaptation to life in wet, densely shady forests, see Giesenhagen, Flora, 1890, p. 417. 2 1. c., p. 374. 3 Those more exclusively acquainted with the British Flora must bear in mind that Hymenophyllum tunbridgense, and Wilsoni, are exceptional among Filmy Ferns as regards their exposed habit. 4 Annals of Botany, vol. IV, p. 347. 130 Bower . — Is E 11 sporangia te or Leptosporangiate ditions : as the Cactaceae and Euphorbiaceae have inde- pendently adapted themselves to life in regions of prolonged drought, by reduction of leaf-surface, and succulent develop- ment of the axis, so may these two distinct stocks have adjusted their details of construction to a damp and often shaded habitat. The thin texture of the leaf is clearly an adaptive character, since it recurs in three distinct families of Ferns, in species of Selaginella and Lycopodium , and also in a minor degree in certain of the higher plants, in all cases a concomitant of shady and damp habitat. The same is probably the case with the filamentous prothallus ; this seeming especially probable in face of the modifications of which prothalli are susceptible when grown in water : when the gametophyte is thus simplified in structure, the sexual organs must needs project, as they do in the Hymeno- phyllaceae. Thus the characters which are commonly cited as demonstrating an affinity between Mosses and Hymeno- phyllaceae may be recognised rather as being of a more directly adaptive nature, such as might be produced in the vegetative system of distinct groups of plants exposed to similar external conditions. Add to this the absence of any support for the affinity in the characters of the sporophyte, and the fact that the Mosses are entirely unrepresented in the earlier rocks, and do not appear until the Tertiaries, and the improbability of a true affinity between the Mosses and Hy- menophyllaceae becomes in my opinion very strong indeed. If this affinity be once given up, then the search for a point of attachment of the Filicineous series is necessarily trans- ferred to the Liverworts, with the further result that the closest similarity to be traced is then with the Eusporangiate Ferns: in the anatomical characters of the sorus and sporangium a measure of support may be found for the suggested affinity, which, however, I would put forward only with that reservation which is necessary where the facts are but scanty. The sporophyte of the Fern corre- sponds to the sporogonium of the Liverwort, and the isolated archesporial cells of the former to the united archesporium the more primitive type in the Ferns ? 1 3 1 of the latter. It is probable that in the course of evolution of the Filicineae, the originally united archesporium became partitioned by bands of sterile tissue, each portion, thus isolated, developing together with its superficial covering of cells into a sporangium : if this were so, it follows that we may recognise in the synangia or so-called * coalescent sporangia ’ of the Marattiaceae, and also in the ‘ sporangio- phore ’ of Ophioglossum , instances of the incomplete separation of the individual sporangia, though the archespore in each is separate from that of its neighbours1. From a com- parative point of view I am disposed to regard these synangia, which are found in more than one series of the Vascular Cryptogams, as primitive in character, and as indicating not a coalescence of sporangia which were distinct in more ancestral forms, but rather an incomplete separation of sporangia, whose distinct archesporial cells were derived by isolation from some such united ancestral archesporium as is seen in the Bryophyta of the present day. If such Eusporangiate forms with synangial sori were the more primitive, it is not difficult to conceive how in plants growing in moist and shaded positions, where the danger of exposure to drought is minimised, the sporangia might have become not only completely separate, but also reduced in bulk, as we see in the progression through the Os- mu ndaceae to the truly Leptosporangiate Ferns : and parallel with this reduction of the sporangium, as I have shown else- where, would have proceeded the reduction in mass of all the other members of the sporophyte. Again, this view that the Eusporangiate Ferns were the more primitive, and the Leptosporangiate derivative and specialised, may throw light upon what I have hitherto re- garded as a perplexing phenomenon, I mean apospory: it was difficult to understand why this obliteration of a marked phase in the alternation should make its appearance in forms which we were accustomed to accept as primitive, seeing that on other grounds it is regarded as a terato- 1 Compare D. Campbell, 1. c. 132 Bower . — Is Eusporangiate or Leptosporangiate logical phenomenon, and not as a reversion. If, however, the views as to the origin of the antithetic alternation, which I have elsewhere put forward, be accepted, and also that the Eusporangiate Ferns be really primitive, apospory appears in a new light : as at present recorded it is found to occur in Leptosporangiate Ferns and Mosses; in forms which, under the present hypothesis, are specialised in accordance with a moist and often shaded habitat ; in these the circum- stances of life on exposed land surfaces, which in my view conduced in the first instance to the antithetic alternation, are mitigated : living, as at least many of the aposporous plants do, in an almost uniformly moist habitat, it is to be expected, rather than wondered at, that the limits of the alternate generations should be obliterated : that the typically terrestrial sporophyte should, on exposure to surroundings more specially favourable to the growth of the gametophyte, grow out directly into the prothallus : and that the spore- formation, which is the distinctively sub-aerial mode of propagation, should be in abeyance: more especially is this to be anticipated in the Hymenophyllaceae when grown in closed cases ; and what more pronounced example of apospory, of actual obliteration of the limits of the two generations, could be afforded than that of Trichomanes alatum 1 ? The very existence of apospory in Leptosporangiate Ferns seems to me to support the view that they are derivative and specialised forms rather than primitive, and these remarks will apply equally to the Mosses, in which aposporous development is induced only under conditions of specially damp culture. In the above pages it will, I think, have been sufficiently shown that the view of the Eusporangiate Ferns as relatively primitive is capable of defence : a comparison of form and development, the palaeontological evidence, and even the facts of apospory, all fall in with this theory, and give it more or less uniform support ; but it is impossible at present to do more than put it forward as an hypothesis, and the question must still be held to be an open one. If the new view be 1 Annals of Botany, vol. I, p. 278. the more primitive type in the Ferns? 133 finally accepted, much of the theoretical writing at the close of my former paper 1 will need to be read in converse. I would, however, remark that whichever opinion be adopted, the facts of my former paper remain, and the serial arrange- ment of the Ferns there based upon the broad area of facts relating to the meristems stands as surely as before. A somewhat modified opinion may, however, be held as regards the families of Leptosporangiate Ferns, and instead of attempting to arrange them all in a linear sequence, it would probably be more in accordance with their characters, as well as with their position as derivative forms to see in them a number of relatively distinct lines of individual development, which might have radiated, so to speak, from the Eusporan- giate centre. The effect of these opinions upon current views as to the main lines of descent would be as follows : In the first place, the thalloid Liverworts would take a more important place as primitive terrestrial plants, which probably approximate to those forms which gave rise to the Filicineous series : from the latter, as well as from the early Bryophyta, derivative forms sprang, which became specialised to a moist and shaded habitat, as an undergrowth below larger organisms : these parallel lines of development culminated in the Lepto- sporangiate Ferns and the Mosses of the present day, both of which may be regarded as blind branches. From some forms allied to our modem Marattiaceae and Ophioglossaceae, the Cycads probably sprang, and from some forms of Lycopo- dineous affinity, the Coniferae. Obviously, if this were so, the effect of recognising the Eusporangiate Ferns as relatively primitive is to carry down to a lower point in the whole scale of plants the insertion of the Gymnospermic type : this would coincide well with palaeophytological facts, for it appears that the Gymnosperms date back to as early formations as the three phyla of the Vascular Cryptogams themselves. That questionable organism Isoetes would now find a natural, but independent, place between the bases of the Filicineous and 1 Annals of Botany, vol. Ill, p. 372, etc. 134 Bower. — Eusporangiates and Leptosporangiates. Lycopodineous series, for, while not distinctly referable to either of them, it shows affinities to both of them as well as to the Cycads. Thus, whatever other strength the view of the Eusporangiate, as the more primitive type for Ferns, may possess, it appears to me to have the effect of making the phylogeny of vascular plants more intelligible, and of har- monising it better with palaeophytology than the converse opinion, which most botanists have hitherto been accustomed to hold. DESCRIPTION OF FIGURES IN PLATE VII. Illustrating Professor Bower’s paper on Ferns. Figs. 1-5 represent sporangia found in sections of nodules from the coal of Halifax and Oldham; 1-4. are from slides belonging to Prof. Williamson; 5. from a slide belonging to Mr. Carruthers. The cabinet numbers are those of Prof. Williamson’s Catalogue. a — annulus, d — point of dehiscence, i = internal cells, x = granular film . Fig. 1. A young sporangium, showing the internal layer very distinctly, and filled with the remains of immature spores. (Cabinet number, 1875.) Fig. 2. An older sporangium which has probably ruptured at d and lost its spores. (Cabinet number, 1020.) Fig. 3. A mature sporangium showing point of dehiscence ( d ) and internal cells. (Cabinet number, 1292.) Fig. 4. A mature sporangium with spores still contained in it, the granular film (jt) may be traced for a considerable distance lining the wall : the number of spores in the section is over 70. (Cabinet number, 1875.) Fig. 5. Portion of a sporangium from Oldham showing internal cells (f) : ( x i5°0 Fig. 6. Sporangium of Todea barbara in longitudinal section ; (x 150.) Figs. 7, 8. Sections of the same in oblique directions, chosen so as to match Fig. 3 as nearly as possible : the position of the figures on the plate, as well as the lettering, correspond to those of Fig. 3 : (x 150.) jfmmls of Botany Voi.v,pi.m Bower del. University Press, Oxford. BOWER.— ON PHYLOGENY OF FERNS. Observations on Phaeozoosporeae. BY T. JOHNSON, B.Sc., F.L.S. Professor of Botany in the Royal College of Science, Dublin. With Plate VIII. BSERVATIONS tending to lessen that large number V_/ of Phaeozoosporeae of which it can be said that the reproductive organs are unknown or only imperfectly known, must be of use, more especially if such observations help in the formation of a more natural system of classification of this group. In the following pages I propose to give the results of the investigation of several brown sea-weeds which the excellent opportunities for research at Plymouth enabled me to examine in considerable detail. i. Carpomitra Cabrerae Kiitz. This plant, added to the British Flora in 1833 by Miss Ball1, is one of the rarest of British sea-weeds. In the sum- mer of 1889 I was so fortunate as to obtain, by dredging, a scrap of the plant from which it was possible to make out the mode of growth of the thallus. Trichothallic grozvth. The tip of a branch of C. Cabrerae is occupied by a tuft of hairs quite visible to the naked eye (Fig. 1). Janczewski says, ‘ S’il est permis de faire quelque conjecture sur 1’accroissement d’une algue d’apres des echan- tillons d’herbier, nous indiquerons que le Sporochmts pedun - culatus et le Caipomitra Cabrerae nous ont paru vegeter d’une maniere analogue a l’accroissement du Cutleria multi jida V Examination of fresh material shows that Janczewski was, 1 Miss Ball’s specimen, with the rest of her herbarium, is in the Herbarium of the Science and Art Museum, Dublin. 2 Ed. de Janczewski, Mem. Sc. Nat. Cherbourg, xix. p. 109. 1875. [Annals of Botany, Vol. V. No. XVIII. April, 1891.] 136 Johnson. — Observations on Phaeozoosporeae. in the main, right in his conjecture. In C. Cabrerae , the branches of which are sub-cylindrical, the hairs at the growing-point (Fig. 2) radiate outwards and, frequently, branch. A thallus-branch with its apical tuft of hairs is roughly comparable to a paint-brush. The hairs are con- nected through the punctum vegetationis with the cells of the thallus, but not so directly in series as in Cutleria multifida. Each hair exhibits basal growth ; cells are given off, on the distal side to the base of the hair, the terminal cells of which fall off, on the proximal side to the body of the thallus. The hairs are free from one another to the merismatic region, but the cells given off on the proximal side are cemented together, and build up the compact thallus. They undergo intercalary divisions and form the parenchymatous thallus, in the branches of which a midrib is, at a little distance from the apex, well marked. It is of interest to note that the hairs, having chlorophyll in their joint-cells, are capable of con- siderable assimilative activity, as a result of which the meris- matic region, from which new cells are being steadily derived, is well supplied with food h It is not difficult to see how, by a grouping together of simple, uniseriate, uncorticate, tricho- thallic branches, the mode of growth in C. Cabrerae can be derived from the well-known mode in Ectocarpus . Reproductive organs. The sessile terminal mitre-like receptacle (as the fertile tip is called) gives to Carpomitra its name (Fig. 3). The sporangia form, with the paraphyses, a dense covering at the tip of a branch. The paraphyses are simple or, more generally, branched, and, when branched, often dichotomous. The sporangia are sessile or stalked, the stalk being provided by the paraphysis (Fig. 4). The terminal cell of the paraphysis contains chloroplastids, and not, as thought by Harvey 1 2, £ probably the remains of sper- matozoa.’ Each sporangium is unilocular and contains a 1 The assimilative powers of the tufts of hairs in the Australian genera Bellotia and Encyothalia must be very great. In these genera the mode of growth is no doubt the same as in C. Cabrerae. 2 W. H. Harvey, Phyc. Brit. PI. 14. Johnson . — Observations on Phaeozoosporeae . 137 large number of spores each of which has a well-marked orange-red pigment granule. I was not able to see either the dehiscence of the sporangium or any movements of the spores. The only fertile plant I had the opportunity of examining was taken in ten fathoms, in August 1890, in Plymouth Sound. The statement, occasionally to be met with, that the tips of the branches in C. Cabrerae are naked, is due to the examination of the plant in a fertile state. In this state, however, microscopic examination shows that the tufts of hair are present though the hairs are reduced to their bases. Indeed there is every indication that the re- ceptacles are transformed branch-apices. The superficial cells of the thallus, instead of forming a compact limiting layer to the thallus, grow out into paraphyses and sporangia. 2. Sporochntjs pedunculatus A g. S', pedunculatus , though rare, is much commoner than Car - pomitra Cabrerae , and can be dredged in tolerable plenty in Plymouth waters 1. Trichothallic growth. The mode of growth of the thallus is essentially the same as in C. Cabrerae (Figs. 5> 6). The thallus is filiform, pinnately branched, each branch bearing a number of alternating shortly-stalked receptacles. Occasion- ally one finds a plant in which the main stem bears the stalked receptacles directly, without the formation of lateral branches. Both main stem, branches, and receptacles have their tips occupied by a tuft of hairs acting as just described in C. Cabrerae. Fig. 2 applies almost equally well to S. pedunculatus. In a ripe receptacle the hairs are quite short, though still recognisable ; the punctum vegetationis is present, though no longer active ; there is everything in fact to indicate that the receptacle is built up on the same plan as the sterile branch. It is not difficult to see that the stalked receptacle is in reality a modified branch of the thallus, as is, less obviously, the case in C. Cabrerae . 1 T. Johnson, Journal Marine Biol. Assoc., New Series, vol. I, No. 3; Flora of Plymouth Sound, p. 286. 1 38 Johnson . — Observations on Phaeozoosporeae . Reproductive organs. The arrangement of the reproductive organs is almost exactly the same as in C. Cabrerae. The sporangia and paraphyses are densely crowded together, at right angles to the surface of the stalked receptacle. The paraphysis is simple or branched. The sporangia are sessile or more usually inserted on the paraphyses, one paraphysis having several sporangia on it at different levels. The spo- rangia rarely reach to the terminal capitate cell of the para- physis, so that, in nature, the only part of the receptacle visible from the outside is the free ends of the paraphyses. Each sporangium is unilocular, and contains a large number of zoospores which appear quite like one another. I frequently kept a plant (it is only when it is quite young that it is not fertile) for 12-24 hours in a darkened bottle through which a steady stream of fresh sea-water was running. On examin- ing the plant under the microscope the zoospores were to be seen escaping in large numbers. They have the usual phaeo- phycean characters, are motionless at their escape, and collect in groups on the surface of the receptacle. In a few seconds the zoospores of a group separate and move off suddenly in all directions. I kept the zoospores under observation for many hours at a time, at nearly all hours of the day and night, and under various conditions, but saw no indication in them of any tendency to fuse with one another. Apparently each one is capable of independent germination. It should not be for- gotten that the conditions under which zoospores of deep-sea plants are examined in a laboratory are very different from those under which they live in nature, 30-40 feet below the surface of the water. A method of observation in which the natural conditions of light, pressure, temperature are carried out, as far as possible, is necessary before negative evidence can be fully relied on. The zoospores are very sensitive to light and quickly arrange themselves in a row, away from the light if at all bright h I was interested to find more than one plant in which the 1 This is a further illustration of the observations of Strasburger and others on the movements of zoospores of Algae. Johnson . — Observations on Phaeozoosporeae. 139 receptacles were themselves branched (Fig. 5). This branch- ing was more frequently seen in plants in which the main stem was unbranched, and bore the stalked receptacles directly. This lends support to the view that the receptacles are modi- fied branches, and shows that the paraphyses themselves are apparently capable of trichothallic growth— one of many in- stances of a want of fixity of function in the various parts of a brown sea-weed. 3. ASPEROCOCCUS Lamour. I have recently shown 1 that in the genus Punctaria Grev. plantlets arise on the old thallus by trichothallic gemmation , from the hairs with basal growth, to be found scattered, in tufts, over the surface of the thallus. I find a very similar gemmation in Asperococcus Lamour. Here and there, on the surface of Asperococcus , solitary hairs with basal growth may be seen2. In an old plant a hair may be seen developing into an Asperococcus plantlet. Quite recently Buff ham has discovered projecting plurilocular sporangia 3 in Asperococcus . There is much evidence that Asperococcus and Punctaria are, through A. compressus , much more closely related to one another than is at present admitted, Asperococcus being placed in the somewhat distant family Sporochnaceae 4. 4. Arthrocladia VILLOSA (Huds.) Duby. A. villosa can be dredged in abundance in Plymouth waters. The mode of growth of the thallus has been described and figured by Falkenberg5. The thallus is filiform, pinnately branched. The joints of the branches are beset with closely crowded whorls of pinnately branched septate filaments. It is on these filaments, towards their base, that the sporangia are formed. Each sporangium is described as stalked, chain- 1 T. Johnson, Linnean Soc., Nov. 1890. 2 J. Reinke, Atlas d. Meeresalgen, Taf. 4. 3 Buffham’s discovery has not yet been announced in print, 4 F. Hauck, Meeresalgen, xi. 5 Falkenberg, Schenk’s Handb. ii. p. 221. 140 Johnson— Observations on Phaeozoosporeae. like, plurilocular. Each compartment of the chain is described and figured as containing only one large zoospore 1. I have examined a very large number of plants of A. villosa and have never found the state of matters as just described to hold good. I have always found each compartment of the chain, on its stalk of 1-3 cells, to contain 10-20 zoospores which even before their escape are to be seen in very active motion. It was possible to see all stages in the mode of escape of the zoospores. The compartments open independently of one another, not necessarily simultaneously or successively, and the zoospores almost immediately after their escape swim off. The zoospores are all alike and, though more pear-shaped, are very similar to those of Sporochnus pednnculatus . They show the same sensitiveness to light. Beyond one or two doubtful cases which could be explained in other ways I saw no signs of any tendency on the part of the zoospores to fuse with one another, though zoospores from different plants were placed together. Each zoospore appears to be capable of independent germination. Not unfrequently the greater part of the whole branchlet falls off, leaving only the base on which the fertile filaments are inserted. Occasionally the sporangia are intercalary, i.e. in addition to the sterile stalk- cells there are several vegetative cells at the apex of the fertile filament (Fig. 10). It seems to me that if these observations are trustworthy, the description of the reproduc- tive organs in A. villosa should be altered. We should no longer speak of the sporangiferous filament as a stalked plurilocular sporangium with one zoospore in each com- partment, but as a stalked chain-like sorus of unilocular, plurisporous sporangia. Falkenberg2 contends, in opposition to Thuret, that the sporangia are plurilocular, basing his opinion on (1) the independent opening of the several com- partments of the chain, (2) the origin of the fertile cells from one mother-cell. On the other hand, it should be noted 1 MM. Crouan figure the compartments plurisporous (Florule du Finistere, 1867, c. 30, 190), without discussing the question of the nature of the sporangia. 2 Falkenberg, op. cit. p. 226. Johnson .- — Observations on Phaeozoosporeae. 141 (1) that if the individual compartments in the chain are unilocular sporangia, each one will naturally have its own opening ; (2) that the form of the sporangiferous filament is such that it must have an unicellular origin ; (3) that in the formation of a plurilocular sporangium the division of the nucleus of the mother-cell takes place repeatedly, forming the rudiments of the zoospores, and that it is only after this that the cell-walls forming the compartments of the plurilocular sporangia are laid down. In A. villosa the mother-cell of the fertile filament divides, successively not simultaneously, into a number of cells, each of which becomes at once, in the chain, an independent cell with its own cell-wall ; each fertile cell then behaves like an unilocular sporangium, the nucleus divides repeatedly, and forms the rudiments of many zoospores in each chamber. Occasionally the apical cells of the filament are vegetative, making the fertile cells inter- calary. This is not merely a question of nomenclature, for the correct interpretation is of no small taxonomic import- ance. Broadly speaking, a plant with unilocular sporangia is of lower position, so far as reproduction is concerned, than one with plurilocular sporangia. Since the zoospores to which they give rise usually germinate independently, the unilocular sporangia may be regarded as asexual organs. Plurilocular sporangia, on the contrary, are known in several cases 1 to be gametangia , the contents showing a most in- teresting gradation in the differentiation of the sexual cells, tending towards the well-known mode of fertilisation in the Fucaceae. I do not overlook the possibility that the pluri- locular sporangia which have hitherto been described in A. villosa may occur, that I may not have had any plants bearing them, and that if I had I may have overlooked them. When my plants were examined as soon as possible after being dredged, they appeared to have monosporous com- partments : but on being kept in a darkened bottle for some hours, the multisporous condition revealed itself. 1 Ectocarpus siliculosus , E. pusillus, Giraudia sphacelarioides. In Dictyosiphon hippuroides the unilocular zoosporangia are gametangia. L 142 Johnson— Observations on Phaeozoosporeae . 5. Desmarestia Lamour. Trichothallic growth . In this abundant and widely-distri- buted genus the mode of growth of the thallus is readily observable (Fig. 12). It has been described in detail by Janczewski1, and later by Falkenberg2. The thallus is pinnately branched, the main stem and all its branches end, when in the growing condition, in an uniseriate septate hair possessed of basal growth. This primary filamentous axis persists as such, and is recognisable in the thickest part (J inch or more) of the thallus. The axial hair is itself abundantly branched in a pinnate manner in its uncortexed part. It is from the basal cells of its pinnules, on the thallus side of its merismatic region, that the whole of the extensive cortex is primarily derived. It will be seen how this mode of growth in Desmarestia , like that in the Tilopterideae, is but a complication of that in Ectocarpus Lyngb. Reproductive organs. Though the genus Desmarestia is so widely distributed and of great systematic importance, the only description of the sporangia is the very brief one by Thuret and Bornet3: ‘ Je rappellerai que dans le Desmarestia , ou du moins dans le D. viridis , car dans le D. Dudresnayi Lamx. 4, MM. Crouan (Florule du Finistere, Tab. 30) figurent une forme de fructification tres difierente, les sporanges se forment egalement dans les cellules corticales. Mais les cellules fructiferes ne presentent aucune modification de forme et de dimension et ne se distinguent des cellules corticales ordinaires que par la nature de leur contenu/ I was successful in finding D. ligulata in a fertile state. The sporangia are, as in D. viridis , unilocular, and, as in it, are only to be distinguished from ordinary cells by the nature of their contents (Figs. 12, 13). In D. ligulata , however, the sporangia are not confined 1 Janczewski, op. cit. p. 106. 2 Falkenberg, op. cit. p. 221, Fig. v. 3 Thuret et Bornet, Et. Phyc. p. 16. 4 The figure referred to in MM. Crouan’s Florule (Tab. 30. 1 91 , Fig. 3) is ‘ ramule de Desm. viridis avec un sporange disseminant ses sporidies.’ It is an incomplete figure representing apparently the escape of numerous spores from a unilocular sporangium. J oknson— Observations on Phaeozoosporeae . 143 to the superficial cortical cells, but are formed also from any joint-cell of the primary cellular axis (Fig. 12), and from any joint-cell of the hair-pinnules (Fig. 14). Hence, morphologically, any cell of the thallus is capable of becoming a sporangium. Each sporangium contains one spore only, occasionally two to four. Each spore is of large size, much larger than the ordinary phaeophycean zoospore, and more like the spore of Pylaiella fulvescens , or of P. litoralis , or of the Tilopterideae. Whether the spore is ciliated, like the ovum of Cutleria , or non-ciliated, like that of Tilopteris , whether it is an ovum, or comparable to the tetrasporangium-like body in Tilopteris , I cannot say. It will be seen that, though my observations on the sporangia have, unfortunately, not gone far, they yet throw some light on the relationship of Desmarestia to the Tilopterideae. Careful microscopic examination of Desma- restia, at all seasons of the year, would yield results of great interest. Summary. 1. In Carpomitra Cabrerae Kiitz., and Sporochnus peduncu - latns A g., the mode of growth of thallus is trichothallic, the apices of the branches being occupied by tufts of innumerable radiating hairs with basal growth. The mode of growth is readily derivable from that in Ectocarpus . The sporangia are unilocular, multisporous. The terminal cell of each paraphysis is assimilative, not reproductive. The receptacle is the modi- fied apex of a thailus-branch, and is, in S. pedunculatus , some- times branched. The zoospores of 5. peduncidatus are sensitive to light, and apparently capable of independent germination. 2. In Asperococcus Lamour, plantlets arise on the thallus by trichothallic germination, from hairs with basal growth, much as in Punctaria Grev., to which Asperococcus is much more closely related than is at present admitted. 3. In Arthrocladia villosa , (Huds.) Duby, the sporangia are unilocular, multisporous, and form stalked chain-like sori. The zoospores after their escape behave like those of 6'. pedunculatus . 144 Johnson— Observations on Phaeozoosporeae. 4. In Desmarestia ligulata , unilocular sporangia, containing one to four spores, and morphologically equivalent to any cell of the thallus, occur. In mode of growth of thallus, and in contents of sporangia, Desmarestia shows a close relationship to the Tilopterideae. EXPLANATION OF FIGURES IN PLATE VIII. Illustrating Mr. T. Johnson’s paper on Phaeozoosporeae. Carpomitra Cabrerae Kiitz. Fig. 1. A small portion of thallus showing tufted apices of branches, slightly magnified. Fig. 2. Longitudinal section of apex of branch showing nature of trichothallic growth. 3 m, Merismatic region of tuft, x 80. Fig. 3. Fertile tip of thallus, slightly magnified, r, Receptacle ; t, remains of apical tuft of hairs. Fig. 4. Surface of receptacle, x 400. p , A branching paraphysis ; s, s', s", stages in the sporangia ; a, cells of surface proper of receptacle. Sporochmts pedunculatus Ag. Fig. 5. Thallus showing stalked receptacles, r\ apical tufts of hairs, t; r, a branching receptacle, slightly magnified. Fig. 6. A maturing receptacle more highly magnified. Fig. 7. Surface of receptacle. Letters as before, x 400. Fig. 8. Zoospore, x 900. Arthrocladia villosa, (Huds.) Duby. Fig. 9. Fertile filament, sc, Sterile cells, x 900. Fig. 10. Intercalary sporangia, x 320. Fig. 11. A zoospore, x 900. Desmarestia ligulata, (Lightf.) Lamour. Fig. 12. Apex of a cortexed branch, pa, Primary septate axis; is, intercalary sporangia ; h, branching hairs, only a few represented ; m, merismatic region. X 120. Fig. 13. Cortical sporangia cs; is, intercalary sporangia on hair-pinnule,, X 240. Fig. 14. Intercalary sporangia is, on branchlet of primary axis, several spores in each, x 240. jlmials of Botany VoLV,mM. Johnson del. University Press, Oxford. The Structure of Pachytheca. II. BY C. A. BARBER, B.A., Scholar of Christ's College , Cambridge, and University Demonstrator of Botany. With Plate IX. IN a former number of this Journal1 I made a study of the structure of Pachytheca as exhibited by two sections belonging to Sir Joseph Hooker. As these were the only survivors of the comparatively large number of slides which had from time to time appeared, it was thought advisable, without delay, to describe such ana- tomical details as could be observed under the microscope. It was pointed out, however, in the course of the paper, that certain difficulties could only be cleared away upon obtaining fresh slides through different parts of the organism, or in a different state of preservation. For this reason it was decided to restrict the description to matters of fact, and to avoid, as far as possible, theoretical considerations concerning the systematic relations of the plant 2. In the paper already referred to it was shown that the plant consisted of the following parts: — (i) a medullary portion of filaments passing in all directions, (2) a cortical portion in which the cell-rows were disposed radially, and 1 Annals of Botany, III. 141. 2 See Hooker, On Pachytheca, Annals of Bot. III. 135, for a summary of the views of different authors. [Annals of Botany, Vol. V. No. XVIII. April, 189s ] 146 Barber . — The Structure of P achy theca. II. (3) a zone of dubious nature, uniting the two, called the zone of oval bodies. The relation between the cortical and medullary tubes could not be determined, and the zone of oval bodies was unexplained. It is hoped that in the present paper both of these difficulties will be removed. Comparatively recently, I have had the good fortune, by the kindness of Mr. John Storrie, Curator of the Cardiff Museum, to come across a valuable series of Pachytheca slides ; and it is with these that I propose to deal in the present paper. The specimens, from which the slides were prepared, occur in a small, isolated portion of Silurian rocks in the neighbour- hood of Cardiff. These have been determined by Professor Sollas to comprise layers between the Old Red Sandstone and rocks of Lower Wenlock age ; and it is in the lower part of the series that Pachytheca is found. The Wenlock beds are well exposed in the Tymawr quarry, a conspicuous object on the right of the road leading to Newport. There are several beds in which Pachytheca occurs. In the uppermost one, which I have carefully examined, there are a great number of pieces of Nematophycus , and a fair sprinkling of Pachytheca : all seeming to be more or less rolled or waterworn. The specimens of Pachytheca are usually perfectly spherical, and sometimes very hard. They seem to consist of an exceed- ingly fine argillaceous matrix in which many of the structural details have been preserved. Mr. Storrie has collected the specimens of Pachytheca and N ematophycus^ for a number of years past, and has himself prepared an exceedingly interesting series of sections. These he has exhibited at various local scientific gatherings, and has now placed them at my disposal for description. 1 The specimens of Nematophycus are, if anything, better preserved than those of Pachytheca ; and I hope, at some time, to publish a paper on the former, since the plant found at Cardiff appears, in certain particulars, to differ from the Canadian specimens kindly sent me by Sir William Dawson. Barber.— The Structure of P achy thee a. II. 147 One of the most remarkable circumstances connected with these slides is the varying manner in which the structure is preserved. It is not easy, by the examination of any one slide, to make much progress ; but, by the careful comparison of a selected series of specimens, certain of the difficulties, which have hitherto clustered around the study of this plant, may be removed. For the sake of clearness I shall refer to the slides selected for description under the numbers 1-13. The figures con- tained in my former paper 1 I shall refer to as B 1-14, and those in Sir Joseph Hooker’s paper2 as H 1-12. DESCRIPTION OF SECTIONS. It is a fortunate matter that Mr. Storrie has succeeded in cutting no less than four sections in different planes through a single specimen of Pachytheca. As these slides may throw light upon the question of the oval bodies , I shall deal with them first. Slide 1 (Figs. 1 and 1 a) contains a radial section through one half of the spherical body of the plant. The medullary portion is, to a great extent, absent, being represented by a few small fragments close to the zone of oval bodies. The cortex is well shown, and consists of a series of radiating tubes, sometimes branching, of clear light yellow substance, bordered by well-defined thick walls. These tubes are separated from one another by elongated spaces, usually rather wider than the tubes, terminating towards the medulla in slightly broader rounded ends. The spaces are bridged across by crystals of the light yellow substance, but are not filled by it : the remainder of the spaces being unoccupied, or more or less filled with a darker, brown, granular mass. It will thus be seen that it is perfectly easy to distinguish the clear radiating tubes from the broken spaces between them ; and it is equally easy, by comparison with the figures 1 Annals of Botany, III. 141. 2 Ibid. III. 135. 148 Barber — The Structure of P achy theca. II. B 1 ,2, and 6 to determine the correspondence of the rounded inner ends of the spaces with the oval bodies of these figures. Internally to the zone of oval bodies a clear, yellowish or brownish layer, of some thickness, lines the whole inner sur- face of the specimen. It will be seen from the figures that the cortical tubes are immediately continuous with this layer, and arise directly from it as so many radiating processes. The inner margin of this medullary 'portion frequently presents circular or cylindrical forms, such as would be obtained by transverse or longitudinal optical sections of tubular cells; but all, or nearly all, traces of vegetable structure have dis- appeared, and these portions, and all other parts of the prepara- tion, appear at present in the form of a mineral concretion around a framework of cells whose outlines have disappeared. Slide 2 (Figs. 2, 2 a) bears a tangential section through the other half of the same specimen, in a plane at right angles to that of section 1. The centre of the preparation is composed of the transverse sections of well-marked circular tubes, with thick walls and broken contents, separated from one another by a clear yellow matrix ; in fact, it presents exactly the opposite appearance to what would have been expected from an ex- amination of Slide 1. As seen in the figure (2), however, as the centre of the preparation is left, and the tubes are cut more and more obliquely, anastomosis of these takes place ; while the outer part of the section shows a state of things the reverse of that at the centre, namely, the presence of a series of more or less obliquely cut clear yellow tubes separated by a broken, dark- coloured matrix. An examination with the high power reveals the following facts (Fig. 2 a). Each of the central tubes has a beauti- fully defined wall of uniform and considerable thickness ; and this wall is marked by perfectly regular parallel striae at right angles to its surface. The contents are more or less broken up, either showing holes, or being filled up by clear yellow crystals or a dark-brown granular mass. Barber . — The Structure of P achy theca. II. 149 Surrounding each tube, and fitting into the interstices be- tween the neighbouring ones, is a set of indistinct sections of much smaller tubes, placed with such regularity that, at the centre of the preparation, each large tube is surrounded by a group of exactly six smaller ones. The smaller tubes have all the appearance of vegetable cells cut transversely, and in size they approach more nearly to the cell-filaments described in the medulla and cortex, and as possibly passing between the oval bodies, in Figs. B ], 2, 5, 6, &c. The appearance of smaller tubes in the clear matrix, al- though frequently very indistinct, is characteristic of all parts of the preparation ; in fact, wherever the yellow matrix is well seen, the sections of the smaller tubes may be sought. This clear yellow matrix thus presents the appearance of a mineral concretion, which has collected around, and follows in all its branchings, a framework of algal filaments ; and it is only in certain parts of the preparation that the form and size of the original cell-rows can be followed. Slide 3 (Fig. 3) contains the remaining two sections cut from the same specimen. These appear to be cut obliquely, that is, halfway between radially and tangentially, and parallel to the section on Slide 1. I shall refer to one of these sections only. A glance at the figures will substantiate the conclusions already arrived at as to the identity of the browner spaces with the oval bodies and their outward prolongations. Indeed, the general resemblance between parts of this section and Figs. B 7 and H 2 is easily recognisable. Further, between the sections of the obliquely cut larger tubes may occasionally be detected the sections of smaller cell-filaments (Fig. 3). From the study of these three slides, it appears probable that the cellular structure, apparent under a low power, is to be considered as a mineral framework, between the parts of which the original plant cells are to be sought. The beauty and regularity of the striated walls of the larger tubes lead one to suggest that they are made up of numerous parallel crystals such as are frequently to be found at the boundaries of crystalline concretions ; and such an assumption is con- 150 Barber . — The Structure of P achy theca. II. firmed by the study of certain other parts of the section, and, more emphatically, by other sections still to be described. Finally, although these tubes are exceedingly regular and quite distinct at the centre of the section, they anastomose in all directions at a short distance from it — a fact irreconcilable with the view that theirs is a typical cell structure. Section 4 is a tangential one, and presents a number of yellow tubes cut across transversely at the centre of the preparation, more or less obliquely peripherally. The yellow tubes are separated by open spaces, or, more usually, by an opaque, dark brown matrix. While these tubes are circular at the centre of the section, a considerable amount of anastomosis occurs at a short dis- tance from it — an arrangement discountenancing the idea that they are the sections of cells. Each tube has a well- marked darker thick concretionary wall similar to those already described for Fig. 2 a. The interior of each tube has a bright yellow matrix with few granules ; and frequently the centre of the tube is occupied by a smaller one, or a sharply defined double circle, exactly resembling the surface view of a bordered pit of Pinus. A fusion of the smaller tubes is never seen, but, where anastomosis of the larger tubes occurs, the smaller ones are found in different parts of the yellow matrix at about their normal distance apart. In this case the smaller tubes are the remains of the cells of the plant, the yellow matrix of the larger tubes being the mineral collected around and infiltrating these. Where the larger tubes are in contact, a fusion of the mineral has taken place, and the result is an apparent anastomosis. A close comparison between specimens 2 and 4 suggests that the great difference in appearance is due to the relative quantity in the two cases of the yellow matrix in which the smaller tubes are always imbedded. While in section 2 there is a preponderance of this substance in the section, in section 4 there is a preponderance of the dark brown mass. In both cases these two constituents of the section are separated from one another by the well-marked limiting layer. Barber . — The Structure of P achy theca. II. 151 Returning now to the smaller tubes in section 4, it is notice- able that some are much more distinct than others. There are all transitions between distinct double circles and an in- definite brownish core. This I regard as suggesting that the clear double circles are not merely transverse sections of the cell-tubes, but that they are the transverse walls of the cell- rows. It is frequently found that, where the central portion of a larger tube is indistinct, a double circle is brought into view by focussing deep into the thickness of the section. In the outer obliquely cut part of the preparation there are more of these double circles present, and they frequently present the flattened or oval shape which would be expected in transverse walls of tubular cells viewed obliquely. Slides 5 and 6 are similar to one another as regards pre- servation. The sections are rather obliquely cut, but they nevertheless include a considerable portion of the medulla. In No. 5 (Fig. 4) the medulla consists of portions of tubes cut in all directions — transversely, obliquely, longitudinally. Towards the zone of oval bodies these fragments are fused together to form a more or less coherent light yellow mass, which will presently receive a closer attention. From this mass the radiating tubes arise. The latter, however, owing to the slight obliqueness of the section, form a clear anasto- mosis between numerous oval bodies, instead of being straight radiating tubes (as in Fig. 1). The tubes, in all parts of the section, have a clear, yellow centre, and a darker, brown 4 wall 5 similar to that in section 4. The spaces between the tubes are unoccupied by any mineral, excepting the occasional presence of the dark brown substance hitherto met with (Fig. a a). Upon carefully examining the outer, fused portion of the medulla, two evidences of structure may be detected. There are, in the first place, numerous ‘ double circles ’ similar to those of section 4. There are also short black lines of surprising sharpness, equal in length to the greater diameter of the double circles ; and, with care, all stages of transition may be 152 Barber. — The Structure of P achy thee a. II. observed from the two circles, through a pair of ellipses, to the black line. It is assumed that the black lines represent the double circles in optical section, and therefore that they are the transverse walls of the cell-filaments (see Fig. 5). For the observation of these particulars section 6 is better than section 5. I have drawn a small portion of the clear border of the medulla, just inside the zone of oval bodies, and obviously formed by the fusion of the tubes in that region. And I have taken advantage of the use of the micrometer screw to focus all parts of the thickness of the section, so as to include as many of the transverse walls as possible. In the medulla of section 5 (see Fig. 4), and, better still, in the corresponding part of section 6, the central part is filled up by a number of sections and pieces of tubes ; and, if we examine these tubes carefully, we shall find the transverse walls in various positions and at various distances. The course of the cell-rows may be readily traced by following the black lines and the general direction of the outer tubes. It is seen in longitudinal sections of the larger tubes that the short black lines occur at regular intervals, and that they only stretch a short distance across the diameter of the tubes. Oc- casionally there are more than one set of dark lines in one and the same tube; and this probably represents the con- dition described as anastomosis of tubes in the transverse sections (Fig. 2). From the occasional regular distance of the black lines, from one another, cells of the filaments may be regarded as from ten to twenty times as long as broad. The double circles are only found in transversely cut tubes, of which they occupy the centres. There are traces, here and there, on each side of a trans- verse wall, of the adjacent longitudinal walls ; but these would probably not be detected had we not a previous suspicion of their existence. We are therefore entirely dependent, for our knowledge of the exact distribution of the algal filaments, upon their transverse walls, which are, indeed, the only parts preserved. This is peculiarly interesting because of the attention Barber . — The Structure of P achy theca. II. 153 drawn, in my former paper, to the thickness of the stopper- like transverse walls (see Figs. B 3 and 4). Although in those sections we had to do with well-preserved longitudinal walls, yet, in cases of difficulty, it is easier to follow the regularly- placed short black lines than the tubes themselves. Thus, upon a careful examination of section 1, with the high power (Fig. 1 a), there may be seen such a transverse wall in the branched radiating tube just beneath the point of bifurcation. And the presence of this small black line is sufficient to determine the question so often asked with regard to Sir Joseph Hooker’s slides, ‘ Do the medullary filaments pass between or into the oval bodies?’ Slide 7 is selected from an interesting batch which Mr. Storrie has prepared since my examination of the specimens so far described. It contains an accurately radial section, and the cells of the cortex are in a similar state of preserva- tion to that of Slides 5 and 6. In the present case, however, the cortex is unique, in that everywhere along the radiating tubes, the short black lines are marvellously distinct (Fig. 6). On the other hand, I cannot detect one double circle. It is worth while, in passing, to note the curious fact that, here, as in the former cases, the black lines do not stretch right across the tubes. This may indicate that only a median part of the transverse wall is preserved. However this may be, the absence of similar longitudinal walls shows that, in the living plant, the characters of transverse and longitudinal walls differed. Slide 8 (Fig. 7). This section differs very greatly in ap- pearance from those on the slides so far dealt with. It corresponds in direction with those on Slides 2 and 4, being a tangential section through the cortex. Under a low power the section appears to consist of numerous tubes with dark brown, granular contents, and very thick clear white walls, — in fact, the resemblance to a transverse section through the stalk of a living seaweed with mucilaginous walls, such as Polyides or parts of Laminaria , is very striking. 154 Barber . — The Structure of P achy theca. II. The tubes at the centre are not, however, always united into a tissue, but frequently leave intercellular spaces be- tween them ; and these latter are filled up by crystals of the same white substance as that of which the mass of the section is composed. The walls are usually composed of two layers, similar to the ‘ shells ’ of thickened cell-walls ; and the outer layer is of the same thickness as the striated walls of Slide 2, without, however, their brown-yellow colour, or well- marked striae. The tubes near the periphery are obliquely cut, and present much the same characters as the central ones. In this part of the section, however, the outer shell, bordering upon the intercellular spaces, is occasionally of a darker colour, and presents numerous parallel striae ; it is, in these parts, identical, in appearance and position, with the thick striated walls already referred to. The brown, granular contents of the tubes in this prepara- tion are evidently, from their disposition and size, the cell- filaments of the plant ; and the white substance forming the tubes is the mineral concretion around them. There is no appearance of structure, whether of transverse or longitudinal walls, in the cells. Slide 9 bears a section cut through the centre of the organism, which presents much the same state of preservation as section 8 just described. The cell-filaments are represented by granules without any transverse or longitudinal walls. In the medulla there are occasionally well-defined, thick, white tubes around these granular cores ; but in the greater part of the section, in- cluding the cortex, the region of oval bodies and most of the medulla, the white mineral has fused to form a translucent basis in which the course of the cell-filaments may be de- termined fairly accurately. It follows, from what has been said concerning the nature of the oval bodies, that they are not present in the best preserved portions of this section. They have hitherto formed interspaces between the cell-containing tubes, and here there Barber . — The Structure of P achy theca. II. 155 are no such interspaces, owing to the greater mass of mineral deposited. In some parts of the section the structure is more broken up, and there the region of oval bodies is fairly definitely indicated. The outer part of the medulla, as would be anticipated from Fig. 5, is characterised by an interweaving of the granular threads ; and the region of the cortex is determined by the regularity of the spaced radiating tubes. Further, it is easy, in certain parts of the section, to trace the radiating filaments directly into the network of threads forming the outer part of the medulla (Fig. 8). In the figure I have drawn such a junction, — leaving out all the cracks and granules of the matrix. I have also used to the full the micrometer screw, in order to trace all con- nections of the filaments. At the same time this connection has not been exaggerated, for a general view of the prepara- tion gives a better impression of intimate union than the drawing of a few isolated filaments 1. This is, I believe, the first specimen, if not the only one, in which cortical and medullary filaments have been seen to join one another. With regard to the branching of the filaments in P achy theca , a careful search in Sir Joseph Hookers specimens produced one or two cases in the outer portion of the cortex (Fig. B 4). The absence of well-defined cells in the present specimens has thus far prevented the detection of any cases of branching. In Fig. 8 there is a possible branching of the filaments, but such a case has not been certainly determined. Slide 10. Here, however, branching is by no means un- common. The slide contains a radial section, more or less resembling specimens 8 and 9 in the manner of preservation. The only traces of the cell-filaments consist in the granular threads already alluded to. While, however, the greater part of the pith and cortex is very poorly preserved, the section has all the appearance of containing the true periphery of the plant in a good state of preservation. 1 In this specimen, as in slides 4 and 10, the nature of the section prevents photographic treatment. 156 Barber,— The Structure of P achy theca, //. In the best parts (Fig. 9), the cells end at a short distance from the periphery, and are bounded externally by a clear yellow layer comparable, in appearance, with the mucilaginous layer bounding many existing Algae. The branching occurs near the extremity of the filaments, and is common — as many as ten distinct branchings appearing in one-fifth of the circumference. There appears to be a frequent tendency towards anastomosis of the ends of the filaments, but this appearance is probably due to the con- ditions of fossilisation. The ends of the filaments are fre- quently dilated (Fig. 9), although this may be due to in- cipient branching. It seems to me possible that this swelling or branching has some connection with the reproduction of the plant. Slide 11 (Fig. 10) contains a beautifully cut section in the same condition as 1, 2, and 3. There is, however, no zone of oval bodies : that is to say, the spaces separating the radiating filaments do not swell at their medullary ends. This is a matter . of importance, as explaining the absence of oval bodies from a number of specimens where we might expect to find them. Thus in all the specimens from the Transition Beds (Figs. B 9—1 1), it was noted that the inner ends of the radiating black lines were not swollen. This difference from Sir Joseph Hooker’s specimens was of so marked a nature, that I hazarded the suggestion that the organisms were possibly belonging to different species. But the present specimen, by the absence of a distinct zone of oval bodies, renders the subdivision of the genus Pachytheca at present superfluous. There are certain other slides of Pachytheca which do not admit of such a ready explanation ; although the present conclusions, founded upon the examination of something like forty slides and specimens, are in no way affected by these unexplained cases. One of these specimens, on Slide 12, has a curious star-like body in its centre much resembling a youthful Rivularia, This may have arisen in the following way. A disturbance in the regularity of the radiating processes Barber . — The Struclrue of P achy thee a. IL 157 may have caused a funnel-shaped divergence of the filaments from one point of the cortex outwards. I have noted several such disturbances and corresponding divergences in radial sections ; and it is perfectly reasonable to suppose that a tangential view of such an arrangement might give the star- like appearance described. On the other hand, the idea which most prominently asserts itself is that we have to do with a mode of reproduction by the endogenous formation of new individuals. Another peculiarity of the same specimen is worthy of note. The part usually occupied by the medulla consists, in this section, of a number of polygonal areas of great regularity. As far as can be judged, this peculiar formation is brought about by the regular arrangement of the filaments in meshes. The Rivularia-like body occupies the centre of the organism, and the peripheral portion, as usual, consists of radiating filaments. Another specimen, on Slide 13, shows, on one side, a large number of more or less parallel, short filament-segments, which pass without interruption far into the medulla. At other parts of the section, the zone of oval bodies, entirely absent at this point of invasion, is found separating medulla and cortex as usual. PRINCIPAL LOCALITIES OF THE FOSSIL. Various places are mentioned in Murchison’s Siluria 1 where Pachytheca is to be found. Among these, it is found in the Bone-bed at Ludlow and Hagley Park near Hereford, and in the Old Red Sandstone of Clun Forest. Specimens from the latter locality are figured under the name of Bufonites (see Plate XXXV, Fig. 30). Almost every place that I have visited, where the transi- tion beds between the Old Red Sandstone and the Silurian crop out, has furnished me with traces of the fossil. I may specially mention the Downton Sandstone near Onibury, Norton and Forge Bridge in South Shropshire, and the Perton 1 1. c. pp. 135, 138, 140, &c. M 158 Barber .— The Structure of P achy theca. II. quarry near Stoke Edith in Herefordshire 1. A small speci- men was turned up by my friend Mr. T. Groom at Ledbury. I am indebted to Mr. Jas. Reid of Blairgowrie, who has forwarded to me specimens of Pachytheca from the Old Red Sandstone of Perthshire2. The specimens are rare and poorly preserved. Of Canadian specimens I have had no means of judging excepting from the figures of Sir W. Dawson 3. I am in- clined to regard the fossils in both countries as identical. Figures of Pachytheca , exhibiting microscopic structure, appear in Rev. J. D. La Touche’s descriptions of Shropshire fossils 4. These figures, I believe, were contributed by Sir J. D. Hooker. Dr. Grindrod found his specimens in the .West Malvern Wenlock Limestone5. I have not myself succeeded in ob- taining any specimens there. With the permission of Pro- fessor A. H. Green, I have examined carefully Dr. Grindrod’s collection, now in the possession of Oxford University, but I found no trace of Pachytheca from this locality. Dr. Hicks has noted Pachytheca in the Denbighshire Grits of the Pen-y-glog slate quarry near Corwen 6. One specimen there is, in the Jermyn Street Museum, which exhibits structure. This specimen has been figured by Messrs. Etheridge and Newton in their appendix to Dr. Hicks’ paper. The specimens which I succeeded in knocking out at this quarry were small and devoid of structure. My best thanks are due to Dr. Hicks for his care in directing me in the somewhat difficult search for these fossils. The specimens found by Mr. Storrie at Cardiff, in the Wenlock rocks of Tymawr quarry, form the subject of the present paper. 1 Annals of Botany, vol. Ill, p. 145. 2 Dawson, Devonian Plants from Scotland, Nature, 10 April, 1890. 3 Dawson, Quart. Journ. Geol. Soc. 1881, XXXVII. 299. 4 La Touche, Handbook of the Geology of Shropshire, Adnitt, Shrewsbury. 5 Hooker, l.c., p. 135. 6 Hicks, Remains of Plants, &c., Quart. Journ. Geol. Soc. 1881, XXXVII. 482. Barber . — • The Structure of P achy theca, II. 159 SUMMARY OF RESULTS. 1. General Structure. P achy theca is a spherical alga con- sisting of a mass of cellular filaments. The cells of these filaments appear to resemble, in general shape, those of a living Cladophora. The body of the plant is divisible into a medullary portion, in which the cell-rows pass in every direction ; and a cortical portion, where the cell-rows are accurately radial, and at equal distances from one another. The cells of these two regions are continuous with one another ; and the point of junction, formerly known as the zone of oval bodies , is charac- terised by a change in the mode of petrifaction — probably partly dependent upon the alteration in the arrangement of the tubes at this point. The cortex may be divided into three zones : — an inner zone, in which the cell-rows are usually separated widely by lacunae in the infiltrating mineral ; a middle zone, consisting of radi- ating, for the most part unbranched filaments ; and an outer zone, near or at the periphery, where branching is frequent. 2. The zone of oval bodies (B 1, 2, &c.), the ■ cellular’ structure seen in Figs. 2 and 3, as well as the radiating dark- coloured tubes of Fig. 1, are spaces between the concretions collected around and incrusting the cell-filaments. 3. The ‘ cellular ’ structure of sections 4 and 8, the network of tubes in the medulla and cortex of sections 5 and 6, and the system of white crystalline tubes seen in specimens viewed under low power by reflected light, are concretionary deposits around the original living cellular framework. 4. This cellular framework of the plant has, with few ex- ceptions, entirely disappeared ; and the tubes left behind are usually four or five times larger than the original cells. In a few cases the longitudinal walls may be traced (see Figs. B 3 and 5, and perhaps specimen 7). More frequently the transverse walls alone are preserved. 5. The transverse walls appear in surface view as a pair of sharply defined concentric circles, remarkably like the M2 160 Barber . — The Structure of P achy theca. II. bordered pits of Pinus (Fig. 5). In profile they appear as short black lines (Figs. 5 and 6). In the best specimens (Fig. 6) these appear to consist of two parts — a black line, and a distinct lens-shaped swelling at its centre : the lens- shaped mass probably appearing as the inner circle in surface view. The transverse walls do not completely bridge the spaces between the longitudinal walls in Fig. 6 — suggesting that only part of the transverse wall is preserved, or that the longitudinal wall itself has disappeared. 6. The lacunae in the inner cortex, known as oval bodies , need not be present (specimens 9 and 1 1). This may explain the constant absence of such bodies in all the specimens examined from the transition beds between Silurian and Old Red Sandstone (Figs. B 8-14). In these specimens the dark lines are evidently comparable with the spaces between the radiating tubes of specimen 11. This similarity does away, at present, with the necessity for subdividing the genus Pachytheca. 7. The specimen figured in Sir Joseph Hooker’s paper (Annals of Bot , III, PI. VIII, Figs. 3-7) I regard as indicating a condition of petrifaction not unmet with in the Cardiff specimens. In fact, certain parts of section 7 remind me strongly of it. The tubes, in these parts, are made up of elongated concretionary masses, separated by spaces of broken material (see Fig. 6) ; and the increase in number of these spaces gives the section the appearance of being composed of elongated parenchymatous cells. 8. The branching in the cell-rows of the medulla is quite possible, although it is difficult to demonstrate (Fig. 8). The branching outside the region of oval bodies seems probable, seeing that the cell-rows are much nearer together in the middle zone than in the inner zone of the cortex. Undoubted branching has only been detected in the outer zone of the cortex, where it is characteristically present (Figs. 9 and B 4). Barber. — The Structure of P achy theca. II. 161 9. As regards the reproduction of Pachytheca nothing is known. Two suggestions have occurred: — (a) Possibly the branchings and swellings at the ends of the cortical filaments may have something to do with spore- formation (Fig. 9). (b) It is suggested by specimen 1 % that a new formation of a daughter sphere may take place within the body of the parent. 10. The principal localities of the fossil are collected at the end of the paper. Pachytheca is found as low in the Silurian as the Denbighshire Grits, and its range extends upwards into the Old Red Sandstone. 1 62 Barber. — The Structure of P achy theca. II. EXPLANATION OF FIGURES IN PLATE IX. Illustrating Mr. C. A. Barber’s paper on Pachytheca. Fig. i. Radial section of one half of Pachytheca , from a photograph, x 32. Fig. 1 a. A small portion of the same section, from a photograph, x 160. Fig. 2. Tangential section through the other half of the same specimen, from a photograph. x 32. Fig. 2 a. A few cells of the same section (drawn), x 270. Fig. 3. A small portion of an oblique section through the same half as in Fig. 2 (drawn). x 320. Fig. 4. A slightly oblique section of Pachytheca on Slide 5, from a photograph, x 32. Fig. 5. A small portion of section 6 (drawn). This corresponds in position with the clear fused zone bordering the medulla externally in Fig. 5. x 320. Fig. 6. A portion of the, cortex of specimen 7 (drawn), x 320. Fig. 7. Tangential section through specimen 8, from a photograph, x 37. Fig. 8. A few granular cell-filaments from Slide 9 at the junction of cortex and medulla, showing the continuity of the cortical and medullary filaments, x 320. Fig. 9. A small portion of the periphery of specimen 10, showing what ap- pears to be the external boundary of the plant. The branching and swelling is pronounced (drawn), x 270. Fig. 10, Section of specimen 11 showing the absence of any zone of oval bodies. (From a. photograph.) x 32. t/Innals of Bo f any From PBoto. &. Draw. Fy CA.BarFer. - . BARBER ON PACHYTHECA. Voi, r;.r/.ji: University Press, Oxford. I29> 386, 4163 926, 9593 960, 1124, 1125, 1126, 1127, 1128, 1344, 1345, 1363,1899. A. radicans, Schk. Avery fine series of forms and varieties of this large bipinnate species, which is spread throughout tropical America. It is very difficult to form an idea of the specific limits of these huge tropical types from herbarium specimens, and perhaps more than one species is covered by the set of numbers. 1019. Asplenium (Anisogonium) God?nani, n. sp. (see Plate XI). 1 67 of the Island of St. Vincent. Rootstock not seen. Whole plant 4 ft. high. Frond oblong- lanceolate, membranous, glabrous except on the main ribs, green on both surfaces, 2-3 ft. long, pinnatifid at the apex, simply pinnate at the base. Pinnae sessile, oblong-lanceolate, entire, the largest 8-9 in. long, 2J.-2J- in. broad, rounded at the base, narrowed gradually to the tip. Veins in pinnate groups, a few in each group anastomosing towards the margin of the pinnae. Sori slender, long ; indusium very narrow, glabrous. Damp forest at the extreme top of the Morne a Garou moun- tain, on the ground, alt. 3100 feet. A very distinct novelty, allied to A. heterophlebium and decussatum. 326. A. marginatum , L. 791, 944, 956. Aspidium semicor datum, Sw. 1 7 1. A. planiagineum, Griseb. 140, 865, 867. A. trifoliatum , Sw. 829. A. trifoliatum , var. A. Plumieri , Presl. 964, 1130, 1360. Nephrodium conterminum , Desv. 15 1. N. Sprengelii , Hook. 789. N. patens , Desv. 705. N. trichophorum , Baker. 855- N. Jenmani, Baker; only about the head- waters of a few mountain streams on the leeward side of the island, alt. 1500-2000 ft. Known before only in Jamaica. 963. A single frond, not identified, possibly a new species, near N. Jenmani and tomentosum. 221, 451, 946. N. brachyodon , Hook. 862. N. ejfusum , Baker. 292, 1021. N. villosum , Presl. 138, 861. N. amplum , Baker. 860. N. furcatum , Hook. 891. N. molle , Desv. 238. Nephrolepis exaltata, Schott. 417. Oleandra nodosa , Presl. 659. Polypodium flavo-punctatum , Kaulf. 43. P. decussatum , L. 317, 697, 754. P. crenatum , Sw. 89? 45 1 ? 785> 946, i347> i348- P- tetragonum , Sw. 858, 1716. P. tetragonum , Sw., var. P. megalodus 3 Schk. 170. P. marginellum , Sw. 1 68 Baker . — On the Vascular Cryptogamia 840. P. serrulatum , Mett. 29. P. trifurcatum , L. Rare, on high mountains, 2500-3500 feet. 2 69, 933. P. trichomanoides , Sw. 142, 932. P . jubaeforme, Kaulf. 5I4, 937. P. suspension, L. 943. P. cultratum, Willd. 919. P. taxifolium , L. 249. P. pectinatum, L. 406. P. sororium, H. B. K. The type and a monster with deeply pinnatifid pinnae after the fashion of P. cambricum, L. 255, 658. P. piloselloides, L. 144, 291, 293, 837, 945. P. loriceum, L. 775. P. incanum , Sw. 688, 798, 1718, 1901. P. aureum, L. Type and varieties. 85, 745, 1364. P. lycopodioides , L. 968. P. repens , L. 173, 479. P. Phyllitidis, L. 1022. P. crassifolium , L, 143. Monogramme seminuda, Baker. 83, 1 1 14, 1 1 15, 1 1 17, 1720. Gymnogramme calomelanos, Kaulf. A series of forms. 1 1 16. 6r. calomelanos , Kaulf., var. G. chrysophylla , Kaulf. 325. (A calomelanos , Kaulf. A handsome decompound finely cut variety, almost denuded of white powder, allied to G. decom- posita , Baker, of which the native country is unknown ; well known in cultivation. 413. G. elongata , Hook. 1 9 1, 315. Meniscium reticulatum, Sw. 1 6 1. Vittaria lineata , Sw. 109. V. remota, Fde. 389. Antrophyum lanceolatum , Kaulf. 1017. A. sub sessile, Kaulf. 1028. Taenitis lanceolata , R. Br. 973. Hemionitis palmata, L. 438. H. cilrifolia , Hook. 967. Acrostichum conforme , Sw., var. A. alalum, Fee. 379, 1138. A. latifolium, Sw. 1139. A. Herminieri, Bory. 380, 1137. A. apodum, Kaulf. of the Island of St. Vincent . 169 1135. Acrostichum (Elaphoglossum) Smithii, n. sp. Densely tufted. Basal paleae dense, subulate, ferruginous. Stipe of barren frond very slender, pale straw-coloured, naked above the base, 3-4 in. long. Barren frond lanceolate, membranous, 8-9 in. long, an inch broad at the middle, narrowed gradually to both ends, furnished with a few small lanceolate brown scales on both surfaces, not ciliated on the edges. Veins fine, distant, distinct, erecto-patent. Fertile fronds much smaller, lanceolate, with a stipe 5-6 in. long. Rare on trees in the mountain forests, alt. 2500-3000 feet. Allied to A. linear e and Aubertii. 376. A. viscosum , Sw. 1134. A. villosum , Sw. 1136. A. undulaium , Willd. Very fine specimens. Rather common locally on trees in the mountain forests, alt. 1500- 2500 feet. 608. A. sorbifolium , L. 281. A. cervinum , Sw. The type and pectinate-pinnatifid form mentioned in Synopsis Filicum. 593. A. aureum , L. 1039. A. praestantissum^ Bory. The taenitoid form. 1133. A. crinitum , L. MARATTIACEAE. 279. Danaea alata, Smith. Exactly matching the plant gathered by Guilding, which is a little different from our other specimens. 307, 692, 1024, 1027, 1029. D. nodosa , Sm. I cannot distinguish D. elliptic a , Sm. LYCOPODIACEAE. 630. Psilotum triquetrum , Sw. 1333. Lycopodium rejlexum , Lam. 1339. Z. dichotomum, Jacq. 301, 735, 1337- A. taxifolium , L. 1335. Z. linifolium , L. 1334. L.f uniforme, Cham. 52, 1332. Z. cernuum , L. 1338. Z. aqualupianum , Spring. 170 Baker —Oil the Vascular Cryptogamia SELAGINELLACEAE. 1 377. Selaginella portoricensis , A. Br. 1 3 75. S..rotundifolia , Spring. 1376. A. apus, Spring. 54, 1 1 9, 235, 1 010. S. flabellata, Spring. The whole collection consists of 145 species or well-marked varieties, represented by 271 numbers. The following species, not collected by the Messrs. Smith, are reported from the island in Grisebach’s Flora of the British West Indies, principally on the authority of the Rev. Lansdowne Guilding. Cyathea Serra} Willd. C. tenera , Griseb. An endemic species, gathered by Caley, represented in the Kew herbarium by a single pinna, labelled in the handwriting of John Smith. Hemitelia grandifolia , Spring. Hymenophyllum hirtellum , Sw. Trichomanes rep tans, Sw. T. br achy pus, Kunze. Adiantum macrophyllum , Sw. A. Kaulfussii , Kunze. A. intermedium , Sw. A. obtusum , Desv. A. trapeziforme , L , var. cultratunu A. tenerum , Sw. Pteris podophylla , Sw. Ceratopteris thalictroides , Brong. Blechnum longifolium , H. B. K. Asplenium alatnm , H. B. K. A. marinum , L. A . lunulatum , Sw. A. furcatum, Thunb. Nephrodium limbatum , Desv. Polypodium flabelliforme, Lam. P. gramineum , Sw. of the Island of St. Vincent . 1 7 1 Monogramme gr amine a, Schk. Taenitis angustifolia , R. Br. Marattia alata , Sm. Equisetum palustre^ L. Out of this list of 26 species I have no hesitation in striking out three as mistakes, the Equisetum , the Monogramme , and Asplenium marinum. There remain the endemic Cyathia tenera and 22 species all likely to occur in any West Indian Island. This leaves, as our census for St. Vincent, 168 species, which is a large number for an island only 140 square miles in area. Most of the species are widely spread through Tropical America, and it will be noticed that only four of them are endemic. 172 Baker . — On the Vascular Cryptogamia , etc. EXPLANATION OF FIGURES IN PLATES X AND XI. Illustrating Mr. Baker’s paper on the Vascular Cryptogamia of the Island of St. Vincent. PLATE X. Hymenophyllum vincentinum , Baker. Fig. 1. A pinna. Fig. 2. A sorus exposed by removal of the valve of the indusium. (Both figures enlarged.) I PLATE XI. Asplenium Godmani, Baker. Fig. 1. Portion of fertile frond (enlarged). Fig. 2. Pinna from lower part of frond. Fig. 3. Apical portion of frond. atnrurls of. Botany VoL. V,Pb.X. M. Smith del. BAKER University Press, Oxford. FERNS OF ST VINCENT. HYMENOPHYLLUM YIWCENTINUM, Balser. Vol. V,FLXT. Annals of Be tony Universitj Press, Oxford. BAKER.— FERNS OF ST VINCENT. ASPLENIUM GOD MAN I , Baker. M. Smith del. On some points in the Anatomy of Ipomoea versicolor, Meissn. BY D. H. SCOTT, M.A., Ph.D., F.L.S. Assistant Professor in Biology (. Botany ), Royal College of Science, London. With Plates XII and XIII. IPOMOEA versicolor , Meissn., a native of Mexico, is fre- quently grown in greenhouses under its older name of Mina lobata , Cerv., and has also been described as Qua - moclit Mina , George Don. Like so many of its genus and order it is a twining plant, and, though an annual, attains a considerable height during its single season of growth. In one of the specimens examined, which was grown in a cool greenhouse, the length of the main stem exceeded 17 ft. (above 5 m.), but no doubt larger dimensions are often reached. For about the first three internodes above the cotyledons the stem is straight. Twining begins in full vigour in or about the fourth internode. (See Fig. 1.) The younger part of the stem is cylindrical and contains a normal ring of bicollateral leaf-trace bundles, the xylem- groups of which soon become united by the cambium to form a continuous zone of wood. The bicollateral structure, which is nearly constant throughout the order, is very characteristic [Annals of Botany, Vol. V. No. XVIII. April, 1891.] N 174 Scott, — On some points in the Anatomy of here1. Each group of internal phloem belongs definitely to one of the leaf-trace bundles, and accompanies the latter on its exit into the leaf. Before considering the modifications of structure which subsequently arise in certain parts of the stem we will trace the relation between the bundle-systems of stem and root, for this plant illustrates with diagrammatic clearness the changes through which bicollateral bundles pass in the tran- sitional region. The two2 obcordate cotyledons each contain four vascular bundles in the petiole, all of which, like those of the leaves generally, are bicollateral. The two median bundles are of large size, and lie close together. The two small lateral bundles are widely separated from them. On entering the axis the bundles of each median pair at once turn their protoxylem-groups towards each other, and pass down through the long hypocotyl to the root. The lateral bundles of the cotyledons on entering the hypocotyl approach each other so as to form two other pairs, at right angles to the former, each lateral pair being thus made up of one bundle from each cotyledon. These bundles also turn their protoxylem-groups towards each other and can only be distinguished from the median pairs by their position. The median pairs are further from the centre, the major axis of the elliptical pith passing through them, while the minor axis coincides with the position of the lateral pairs. The opposite median pairs are separated by about 14, the lateral pairs by about 9 pith cells. Lower down the pith of the hypocotyl becomes circular, and here all the four pairs of bundles are in all respects similar. The diagrammatic section (Fig. 2) is taken at a point where the pith is still somewhat elliptical, C-C being the median plane of the cotyledons. The bundles of the plumular leaves fuse with the lateral 1 Cf. Solereder, Ueber den systematischen Werth der Holzstructur bei den Dicotyledonen, 1885. 2 Occasionally three cotyledons are developed, but I did not investigate these exceptional seedlings. Ipomoea versicolor , Meissn. 175 cotyledonary bundles as soon as the latter enter the stem, so that the hypocotyl is traversed by the cotyledonary traces only. Each pair of bundles in the hypocotyl has a common strand of internal phloem lying just within the two converging pro- toxylem-groups. As we trace the bundles down towards the root we find that in each pair the protoxylem-groups slowly approach each other, and as this goes on the internal phloem- strand passes out between them. Three stages of their course are shown in Figs. 3, 4, and 5, taken respectively at the levels a , b , and c shown in the sketch of the seedling (Fig. 1). As the root is approached the two xylem-groups of each pair meet and fuse, turning their protoxylem outwards. At this point the internal phloem is seen forming two strands, one on each side of the xylem plate (Fig. 4. ph2). Fower down still the internal phloem passes completely to the outside of the xylem (Fig. 5) and ultimately joins the external phloem. The later stages of the transition are passed through within a very short space, as is shown by the relative positions of the sections as marked in Fig. 1. The main root is tetrarch, and its four xylem plates, corresponding to the four pairs of cotyledonary traces, eventually meet in the centre, the pith dying out. It will be seen that the course of the bundles agrees with the well-known type of Phaseolus. Its regu- larity is very favourable to tracing the passage of the internal phloem. The transitional region between stem and root shows remark- able peculiarities when secondary growth begins, and these are now to be described. The upper and younger part of the stem is cylindrical and typical in structure, as already stated. The lower part of the stem, however, has a flattened form ; its greater diameter may be as much as double the lesser, the latter being equal to the diameter of the cylindrical portion. The region show- ing this flattened form may be many feet in length in well- grown specimens, but the peculiarity is most marked in the neighbourhood of the cotyledons. The flattened appearance N 2 1 7 6 Scott. — -On some points in the Anatomy of is due to the presence of two great masses of secondary tissue, chiefly xylem, which have been added one on each side of the stem. The original ring of xylem can be traced all round ; at the flat sides it has received little or no increment, while on the prominent faces the additional masses of wood and bast have been superposed upon it. The xylem of these masses is characterized by the presence of many enormous pitted vessels, attaining -25 mm. in diameter, while those of the ordinary ring scarcely measure -05 mm. The phloem is decidedly more developed on the prominent faces than elsewhere, but the difference is not so marked as in the xylem. The flattened region extends to the hypocotyl, in which the median line of the prominences is at right angles to the plane of the cotyledons. Towards the root, however, the thickening becomes more uniformly distributed until the transverse section is once more circular (Fig. 2). In the upper part of the flattened region there is nothing anomalous except the unequal distribution of the secondary tissues, which also occurs in some other Convolvulaceae. A little thin-walled parenchyma is present in the secondary xylem. In the lower internodes, however, the structure is much less regular and in the hypocotyl is extremely anomalous (cf. Fig. 2). The secondary masses of wood are broken up in all directions by bands and patches of thin-walled parenchyma containing isolated strands of phloem, in which the sieve- tubes and companion-cells are of normal structure, and per- fectly similar to those of the external and medullary phloem. The diagrammatic section in Fig. 2 is taken from the lower part of the hypocotyl where the secondary thickening is nearly uniform all round. The parenchyma of the wood, whether forming rays or isolated groups, is everywhere tra- versed by strands of phloem. In these transitional regions a large proportion of the whole phloem is interxylary. The investigation of developmental stages leaves no doubt that these masses of parenchyma, together with the phloem 177 Ipomoect versicolor , Meissn . which they enclose, are produced centrifugally on the inner side of the normal cambium (see Fig. 6). The same cambium subsequently adds lignified tissue outside them, and they thus become enclosed in the wood (cf. Figs. 6 and 7). The phloem-groups themselves may either be formed directly from the cambium or by the subsequent division of the parenchy- matous cells. Both processes occur side by side, as is also the case in Asclepias and Thladiantha , to be described elsewhere. The parenchymatous islands with their strands of phloem extend up into the first internodes above the cotyledons and gradually disappear. They seem never to end blindly in the wood, but ultimately to abut on the cambium. Above the cotyledons they can only communicate with the medullary phloem at the nodes. The main root in its lower portion is normal. Here, as in the stem, the interxylary phloem ends in contact with the cambium. Ipomoea versicolor then presents the curious case of a plant in which the greater part of both stem and root is normal, while the region for some distance on both sides of the transition possesses a complicated system of interxylary phloem. The anomalous transitional region, with its abundant conducting tissue, serves no doubt as a temporary store-house of food-material, reserved perhaps in part for the period of flowering. A word must be said on the relation of the medullary phloem to the phloem-systems of the mature root. As already ex- plained, the former is continuous, at the lower end of the hypocotyl, with the normal external phloem. Then secondary growth begins ; at the points where the medullary phloem passes out the cambium necessarily cuts through it. Its con- tinuity, however, is not altogether interrupted, for opposite each bundle-pair, through which the out-going phloem passes, the cambium forms a parenchymatous xylem-ray containing, as already stated, strands of interxylary phloem (see Fig. 5 ; the diagram, Fig. 2, is taken above the exit of the medullary 178 Scott. — On some points in the Anatomy of phloem). With these strands the medullary phloem remains in permanent continuity. Thus the interxylary phloem of the transitional region is in communication both with the medullary and the external phloem-systems of stem and root. A further complication of structure appears in the older hypocotyl, for an internal cambium arises by the divisions of the outer cells of the pith, starting from the internal phloem- groups, and sometimes extending nearly round the whole circumference. It produces some additional medullary phloem internally, and also gives rise occasionally to a few lignified elements on the side towards the wood. The chief points then to be noted are the following : — 1. The internal phloem extends downwards into the hy- pocotyl and passes out between the converging protoxylem groups of each cotyledonary pair of bundles, thus joining the external phloem of the root. 2. The hypocotyl and the adjacent parts of stem and root have a complex secondary wood containing numerous strands of interxylary phloem, imbedded in parenchyma. These c phloem-islands ’ are produced centrifugally by the cambium. As regards the course of the internal phloem in the transi- tion from stem to root, Ipomoea versicolor may be taken as typical of plants with bicollateral bundles generally. A full discussion of this subject, with references to the literature, will be found in a forthcoming paper by Mr. Brebner and myself. I am not aware that the existence of phloem-islands in the wood has previously been observed in any Convolvulaceae. The very remarkable anomalies described by Schmitz1 and Dutailly2 in the roots of certain perennial members of the 1 tiber die Anat. Structur der perennirenden Convolvulaceen-Wurzeln, Bot. Zeitung, 1875, p. 677. His results are summarized by de Bary, Comp. Anat., Eng. ed. p. 606. Tschirch, Angewandte Pflanzenanatomie, 1889, figures a trans- verse section of the root of Ipomoea Purga. 2 Sur quelques phenomenes . . . dans le tige et la racine des D icotyledones, Paris, 1879. Ipomoea versicolor , Meissn. 179 order are of quite a different kind, depending on the appear- ance of new cambial regions in the secondary parenchyma of xylem and phloem. Both the preparations and drawings for this investigation have been made by Mrs. D. H. Scott. The plants were raised from seed under glass. i8o Scott .« — Ipomoea versicolor , Meissn . EXPLANATION OF THE FIGURES IN PLATES XII and XIII. Illustrating Dr. D. H. Scott’s paper on Ipomoea versicolor , Meissn. The following lettering is used throughout the microscopical figures : — c1 = normal cambium. pie- — normal external phloem. //z2 = medullary phloem. phz = interxylary phloem. px = proto xylem. xi = primary xylem. x2= secondary xylem. P — pith* £ = endodermis. Fig. i. Seedling, showing the whole plant, with the cotyledons and the first few leaves. G-G level of the ground. The upper internodes are already twining round a support. b, and c, positions at which the sections shown in Figs. 3, 4, and 5 were taken. Two-thirds of natural size. Fig. 2. Semi-diagrammatic transverse section of the hypocotyl. C-C median plane of the cotyledons. red— primary xylem of the cotyledonary traces. yellow — secondary xylem. blue = phloem, medullary, interxylary, and external. brown = periderm. The parenchyma is left white. Fig. 3. Part of a transverse section taken at a (Fig. 1). A pair of cotyledonary bundles is shown, with converging protoxylem, and a common group of medullary phloem just within them. Fig. 4. Corresponding section much lower down, at b (Fig. 1). The xylem- groups are now united with outwardly-directed protoxylem. The medullary phloem is passing to the exterior, forming two strands, one on either side of the xylem-plate. The whole has been enclosed by secondary wood. Fig- 5- Corresponding section somewhat lower, at c (Fig. 1). The medullary phloem now lies to the outside of the xylem-plate. Observe that the cambium is here beginning to form a medullary ray. Fig. 6. From a much older hypocotyl, showing a parenchymatous ‘island’ with interxylary phloem, in course of development. The cambium is beginning to form new wood and thus complete the formation of the island. Fig. 7. From the same hypocotyl as Fig. 6, showing a similar island completely imbedded in the wood, and containing much interxylary phloem. The arrow cx points towards the cambium. Figs. 3-7 are X330 diam. ijfmuxZs of Bo6ajiy Vol, V, FI. HI. University Press, Oxford.. tjfnnaZs of Botajzy VoL, V, PL. XII. R. Scott del. University Press, Oxford. 'ipx/ f 7 Jt c! Y \ T A ""■-JLS \ / \ N) — ( j — " FFm y^T \ [■f; ' c SCOTT. ON ANATOMY OF IPOMAEA. rfnuals of Botany Vol.V/Pl.ML R. Scott del. University Press, Oxford. SCOTT. — ON ANATOMY OF 1POMAEA. A Summary of the new Ferns which have been discovered or described since 1874. BY J. G. BAKER, F.R.S. Keeper of the Herbarium 3 Royal Gardens , Kew. With Plate XIV, HE second edition of Hooker and Baker’s Synopsis -A- Filicum (now out of print) brings the enumeration of genera and species up to the year 1874. Since that date a large number of novelties have been discovered and described and so much fresh light has been thrown by morphological investigation on the taxonomic relations of the different groups of plants included under FlLICES that it is time for a new handbook. As there is not any chance of this being produced at present, I propose in this paper to attempt a general sum- mary of what has been added to our knowledge in respect to species during the last sixteen years. I do not intend to describe again the plants that have been described already ; but merely to indicate their position in the sequence followed in the Synopsis , in the same way as in the supplement published in the second edition. Most of the larger collections that have been received at Kew have been already published in Britten’s Journal of Botany and in the Transactions and Journal of the Linnean Society, but a considerable number of new species which have been received from time to time are still unnoticed. Of many of the plants which have been described by other authors we possess authentic specimens. Some of these I can only place as synonyms, and others, measured by the standard of [Annals of Botany. Vol, V. No. XVIII. April, 1891. ] 1 82 Baker.— A Summary of the new Ferns specific difference adopted in Synopsis Filicum , as forms or varieties. Of the distinctness of published novelties of which I have not been able to see specimens, it is almost impossible to judge, but I have indicated the position they would occupy in the Synopsis as well as I could from the published descrip- tions. In a few cases fresh material that has been received shows that species that are passed over in the book for want of knowledge ought to be maintained, or that species kept up as distinct in the book ought to be combined. Besides innumerable papers in journals, in the proceedings and transactions of societies and in local floras that include ferns (which I need not attempt to enumerate, as they will appear in the citations), the two principal books that concern our subject that have appeared since 1874 are Beddome’s most useful Handbook of the Ferns of British India, published at Calcutta in 1881, and Father Sodiro-s e Recensio Cryptogama- rum Vascularium Provinciae Qtiitensis ’ published at Quito in 1883. The sixteenth century of Hooker’s leones is devoted entirely to Ferns. The principal collections which contain new species have been made in Madagascar by Pool, Miss Gilpin, Kitching, Baron, Humblot, Hildebrandt and Last ; in China by Henry, Faber, Ford, Hancock, Maries and Delavay ; in Perak by Scortechini ; in Tonquin by Balansa ; in the Malay archipelago by Beccari, Burbidge and Dr. Hose (Bishop of Singapore and Sarawak) ; in New Guinea by Beccari and Sir William Macgregor ; in New Caledonia by Vieillard and Balansa ; in Polynesia by Moseley (Challenger expedition), Horne, Sir J. B. Thurston and the Rev. R. B. Comins ; in the Western United States by various collectors ; in Mexico by Pringle, Parry and Palmer; in Costa Rica by Harrison and Cooper; in the West Indies byjenman, Hart, Nock, Sherring and Fendler ; on the Roraima expedition by im Thurn ; in New Granada by Kalbreyer ; in Ecuador by Father Sodiro ; and in Brazil by Glaziou. In this enumeration the species are numbered as in the Synopsis Filicum. Novelties are indicated by an asterisk attached to the numbers of the species to which they are most nearly allied. discovered or described since 1874. 183 GLEXGHENXACEAE. Genus 2. Gleichenia Sm. 3. G. eircinata, Sw. I cannot separate specifically G. patens, Colenso in Trans. New Zeal. Instit. 1888, 212. 4. G. rupestris, R. Br., must evidently be placed as a mere variety of G. eircinata . 8. G. littoralis, Colenso, in Trans. N. Zeal. Inst. 1883, 334, I cannot separate from G. flabellata. 12*. Mertensia littoralis, Philippi, Descr. Nuev. Plant. 1873, 104. Chili. Not seen. 15. G. subandina, Sodiro, Recens. 5, and G. hypoleuca, Sodiro, Recens. 8, Andes of Ecuador, I should place as varieties of G. revoluta. 17. G. seminuda, Moore, Ind. Fil. 383, Columbia, G. blepharilepis, Sodiro, Recens. 6, and G. leueocarpa, Sodiro, Recens. 8, Andes of Ecuador, I should place as varieties of G. pubescens. 17*. G. intermedia, Baker, in Journ. Bot. 1887, 24. Costa Rica, Cooper. Intermediate between pubescens and dichotoma . There are two varieties, -flexuosa and dissiti/olia. 19. G. Brackenridgei, Fourn. in Ann. Sc. Nat. ser. 5, XVIII, 269, New Caledonia and Fiji, and G. oeeanica, Kuhn, Hook, and Baker, Syn. Fil. edit. 2, 449, should probably be classed as varieties of G. flagellar is. 23. G. linearis, Clarke, in Trans. Linn. Soc. ser. 2, I 428, ( Poly - podium lineare , Burm.), is a synonym of G. dichotoma , Hook. CYATHEACEAE. Genus 4. Cyathea Sm. Bommer proposes to divide Cyathea into three genera, viz. 1, Cyathea , indusium of one single indehiscent piece; 2, Eatoniopteris , indusium of one piece, membranous, breaking up into fragments ; 3, Fourniera , indusium formed of a number of narrow hyaline im- bricated scales. For my own part, I feel more inclined to unite Hemitelia to Cyathea than to divide Cyathea as it now stands. NEW WORLD SPECIES. 3*. C. Nockii, Jenm., in Journ. Bot. 1879, 257. Jamaica, Nock. Indusium of C. arborea , but frond bipinnate. 184 Baker —A Summary of the new Ferns 3*. Cyathea Boni, Christ, in Journ. de Bot. 1890, p. 410. French Tonquin, Bon. Near C. Hookeri , of Ceylon. 4*. C. jamaicensis, Jenm., in Journ. Bot. 1882, 323. = C. arborea var. concinna . Baker, in Journ. Bot. 1881, 52. Jamaica. 4*. C. monstrabilis, Jenm., in Journ. Bot. 1881, 273. Jamaica. Probably an abnormal form. 4*. C. conquisita, Jenm., in Journ. Bot. 1882, 324. Jamaica, Wilson , 134. 4*. C. pendula, Jenm., in Journ. Bot. 1882, 324. Jamaica, Wilson , 16. This and the last are known only from specimens sent long ago by Wilson to John Smith, whose fern-herbarium is now at the British Museum. 4*. C. erassipes, Sodiro, Recens. 10. Andes of Ecuador. Maybe a variety of C. insignis , Eaton. 10*. C. ocanensis, Baker, n. sp. Trunk 8-15 feet long. Frond ample, bipinnatifid, subrigid, glabrous. Pinnae oblong-lanceolate, 1-1^- ft. long. Pinnules lanceolate caudate, 2J-3 in. long, -J-f in. broad, cut down by a broad wing into oblong tertiary segments in. broad. Veins 10-12-jugate, indistinct, forked. Sori crowded, costular; indusium very fragile. New Granada; province of Ocana, Kalbreyer\ 608. 10*. C. corallifera, Sodiro, Recens. n. Andes of Ecuador, Sodiro. 10*. C. fnlva, Sodiro, Recens. n. Andes of Ecuador, Sodiro. 10*. C. aspidioides, Sodiro, Recens. 14. Andes of Ecuador, Sodiro. This and the last two are closely allied to C. divergens, Griseb. = C. petiolulata , Karst. 11*. C. dissolnta, Baker; Jenman, in Journ. Bot. 1881, 52. Jamaica, Jenman. Between C. gracilis and Schanschin. 14*. C. puberula, Sodiro, Recens. 16. Andes of Ecuador, Sodiro. Not seen. ‘ Near C. straminea , Karst/ 20*. C. Copelandii, Kuhn & Luerss. in Abhandl. Nat. Bremen, VII, 278. Island of Trinidad, South Atlantic, Copeland. I cannot from the dried pinnae distinguish this clearly from the widely-spread continental C. Schanschin , Mart. 20*. C. ruiziana, Klotzsch, in Linnaea, XX, 439. Fronds ample, bipinnatifid, glabrous, moderately firm ; main rachis densely furfuraceous and muricated. Pinnae oblong-lanceolate, 1^ ft. long, 8 in. broad ; rachis densely furfuraceous with many ovate-lanceolate glossy black paleae with a pale edge. Pin- discovered or described since 1874. 185 nules lanceolate, 4 in. long, J- in. broad, with many ovate and ovate-lanceolate paleae on the ribs beneath : tertiary segments oblong. Veins 8-10-jugate, deeply forked. Indusium very fragile, Peru, Pavon. Described from a type specimen lent by Mr. H. C. Levinge, in 1885. 12. C. mexieana, Schlecht. So far as I can judge from sterile fronds, the plants which have been widely spread in gardens under the names of Alsophila Malzinei and A. Vangeerlii, are forms of this species. OLD WORLD SPECIES. In no group of Ferns have the additions made since 1874 been more numerous than in the Cyatheas and Alsophilas of the Old World. 26*. C. Thoms oni, Baker, in Journ. Bot. 1881, 180. Plateau north of Lake Nyassa, Joseph Thomson. Very near C. Dregei of the Cape. 29*. C. mossambicensis, Baker, n. sp. Frond ample, bipinnate, moderately firm, green and glabrous on both surfaces ; rachis pale brown, naked, unarmed. Pinnae lanceolate, a foot or more long, 2 in. broad; pinnules linear-oblong, obtuse, distinct, crenate, J in. broad. Central veins of the pinnules twice forked. Sori placed nearer the midrib than the margin. In- dusium a firm persistent cup with a truncate mouth. Namuli Makua country, Last, collected in 1887. Near C. cameroon- iana , Hook. 33*. C. Lastii, Baker, in Journ. Bot. 1891, 13. North-West Mada- gascar, Last. 33*. C. regularis, Baker, in Journ. Linn. Soc. XXV, 349. Mada- gascar, Baron. 33*. C. discolor, Baker, in Journ. Linn. Soc. XV, 412. Madagascar, Pool. 33*. C. serratifolia, Baker, in Journ. Bot. 1884, 139. North-West Madagascar, Humblot , 278. Very distinct; cutting of Alsophila Taenitis. 33*. C. polyphlebia, Baker, in Journ. Linn. Soc. XX, 303. Mada- gascar, Baron. 33*. C. segregata, Baker, in Journ. Linn. Soc. XX, 303. Mada- gascar, Baron. 1 86 Baker. — A Summary of the nezu Ferns 33*. Cyathea rigidula, Baker, in Journ. Linn. Soc. XXII, 534. Madagascar, Baron . 34*. C. ligulata, Baker, in Journ. Bot. 1884, 140. North-West Madagascar, Humblot , 299. 33*. C. hirsuta, Baker, in Journ. Bot. 1884, 140. North-West Madagascar, Humblot , 262. 33*. C. Hnmblotii, Baker, in Journ. Bot. 1884, 140. North-West Madagascar, Humblot , 264. 33*. C. Hiidebrandtii, Kuhn, in Ind. Sem. Hort. Berol. 1875, 20. Johanna Island, Hildebrandt , 1747. 34*. C. leptoehlamys, Baker, in Journ. Linn. Soc. XXII, 535. Madagascar, Baron. 34*. C. quadrata, Baker, in Journ. Linn. Soc. XV, 41 1. Mada- gascar, Pool. 34*. C. appendiculata, Baker, in Journ. Linn. Soc. XV, 411. Madagascar, Meller. 36*. C. sumatrana, Baker, in Journ. Bot. 1880, 209. Sumatra, Bee carl , 438. 38*. C. suluensis, Baker, in Journ. Bot. 1879, 65. Sulu archi- pelago, Burbidge. 39. C. sarawakensis, Hook. The Bishop of Singapore and Sarawak has sent a series of specimens demonstrating that C. lobbiana , Hook, and Alsophila alter nans > Hook, are forms of this species. 40. C. assimilis, Hook. C. beccariana , Cesati, in Becc. Fil. Born. 3, belongs here. 41*. C. philippinensis, Baker; Alsophila philippinensis , Hort. Veitch. Trunk short, slender ; paleae large, linear, pale brown. Frond bipinnate, oblong-rhomboid, 3 ft. long, 1 ft. broad, narrowed from the middle to the base; rachises of frond and pinnae densely paleaceous. Pinnae lanceolate, central largest, 6-7 in. long, ij in. broad; pinnules ligulate, crowded, sessile, \ in. broad, entire or crenate, with forked veins and a single row of sori between the midrib and edge ; indusium moderately firm, but breaking up into pieces. Philippines, introduced into cultivation by Messrs. Veitch. Described from a plant that pro- duced fruit at Kew in Feb. 1878. 44*. C. schisoehlamys, Baker, in Journ. Bot. 1880, 209. Sumatra, Becc art , 439. discovered or described since 1874. 187 47*. C. brevipinna, Baker, in Benth. FI. Austral. VII, 709. Lord Howe’s Island. 47. C. medullaris, Sw. I cannot separate C. polyneuron, Colenso, in Trans. New Zeal. Instit. 1878, 429. 48*. C. Macgregori, F. M. & Baker, in Journ. Bot. 1890, 104. Highlands of New Guinea, Sir W. Macgregor. 49. C. dealbata, Sw. I cannot separate C. tricolor, Colenso, in Trans. New Zeal. Instit. XV, 304. 50*. C. Muelleri, Baker, in Journ. Bot. 1890, 104. Highlands of New Guinea, Sir W. Macgregor. 52*. C. Moseleyi, Baker, in Journ. Linn. Soc. XV, 104. Admiralty Isles, Moseley (Challenger expedition). 52*. C. fusea, Baker, in Malesia, III, 31. Fly river, New Guinea, D' Albertis. 52. C. Whitmeei, Baker, in Journ. Bot. 1876, 343. Samoa, Whitmee. 53. C. Moorei, Baker, = C. Macarthurii , F. M., Benth. FI. Austral. VIII, 708 ; the latter being the earliest specific name. 53*. C. scabra, Baker, in Journ. Bot. 1876, 343. Samoa, Whitmee. 54*. C. Thurstoni, Baker, in Journ. Bot. 1884, 182. Fiji, Sir J. Thurston. 54*. C. samoensis, Baker, in Journ. Bot. 1876, 9. Samoa, Whitmee. 55*. C. funebris, Hort. Linden; Foumiera funebris , Fourn. in Linden, 111. Hort. XXIII, 99. New Caledonia; not seen. Genus 5. Hemitelia, R. Br . NEW WORLD SPECIES. 11*. H. Hartii Baker, in Journ. Bot. 1886, 243. Chiriqui, Hart. 15*. H. cystolepis, Baker; Cyathea cystolepis , Sodiro, Recens. 8. Andes of Ecuador. Indusium present, but very small. 15*. H. firma, Baker, in Journ. Bot. 1877, 161. Andes of Ecuador, Sodiro. 15*. H. erenata, Sodiro, Recens. 18. Andes of Ecuador, Sodiro. 15*. H. Joadii, Baker, n. sp. Frond ample, bipinnatifid, moderately firm, green and glabrous on both surfaces, with a few small white membranous paleae on the midribs of the pinnules beneath ; rachis unarmed, glabrous. Pinnae oblong-lanceolate, 1 88 Baker.— A Summary of the new Ferns i-ii ft, long, 5-6 in. broad; pinnules lanceolate, sessile, f-f- in. broad, cut down to a broad wing into oblong, distinctly- toothed tertiary segments ^ in. broad. Veins simple, distinct, 6-7-jugate. Sori marginal ; indusium firm, J-cupshaped. Santa Marta, Joad, (1863). 15*. Hemitelia Traillii, Baker, n. sp. Fronds ample, bipinnatifid, moderately firm, green and glabrous on both surfaces, slightly scaly on the ribs beneath ; rachis unarmed, furnished with a few large lanceolate brown scales. Pinnae oblong-lanceolate, 2 ft. long, 8-9 in. broad ; pinnules lanceolate petioled, above an inch broad, cut down to a narrow wing into oblong-lanceolate inciso-crenate tertiary segments J in. broad. Veins forked, 8-9- jugate. Sori medial, placed at the fork of the veins ; indusium minute. Amazon valley, North Brazil, collected by Professor Traill of Aberdeen in 1874. 15*. H. Sherringii, Jenm., in Journ. Bot. 1886, 266. Rose-hill, Jamaica, Sherring ; only one plant seen. 15*. H. parvula, Baker. First published as Alsophila parvula, Jenm., in Journ. Bot. 1879, 258; afterwards as Hemitelia microsepala , Jenm., in Journ. Bot. 1886, 2 66. Jamaica. OLD WORLD SPECIES. 16*. H. brunoniana, Clarke, in Trans. Linn. Soc. ser 2, Bot. I, 430 , — Amphicosmia brunoniana , Beddome. India orientalis. Included under Alsophila contaminans , in Syn. Fil. p. 41. 16*. H. decipiens, J. Scott, East Himalayas = Cyathea decipiens , Clarke & Baker, in Journ. Linn. Soc. XXIV, 409, and the South Indian H. Beddomei, Clarke, in Trans. Linn. Soc. n. ser. I, 429, is very nearly allied to it. Both of them only differ from Cyathea spinulosa in the indusium. 1 8. H. Smithii, Hook. I cannot separate H. stellulata, Colenso, in Trans. New Zeal. Instit. 1885, 222. 19*. H. glandulosa, Kuhn, in Hildeb. PI. Madag. Exsic. No. 4176. Frond ample, bipinnate, moderately firm, green and glabrous on both surfaces ; rachis unarmed, naked beneath. Pinnae oblong-lanceolate, 1J-2 ft. long, 8-10 in. broad; pinnules sessile, lanceolate, f-J- in. broad, cut down to the rachis into distinct linear-oblong crenulate tertiary segments in. broad. discovered or described since 1874. 189 Veins 10- 12 -jugate, forked. Sori subcostular ; indusium minute. Central Madagascar, Hildebrandt. Very near H. Mel- leri, Baker. 19*. H. GodefFroyi, Luerss., in Mus. Godef. II, 4. Queensland, Mrs . Dietrich. Not seen. See Benth. FI. Austral. VII, 709. Genus 6. Alsophila, R.Bv. NEW WORLD SPECIES. 11*. A. Sodiroi, Baker; A. alata , Sodiro, Recens. 19, non Fournier. Andes of Ecuador, Sodiro. Near A. leucolepis and paleolata. 12*. A sessilifolia, Jenm. in Journ. Bot. 1882, 325. Jamaica, Wilson (Herb. J. Smith only). 12. A. aspera, R. Br. I cannot clearly separate the Trinidad A. echinata, Moore, Ind. Fil. 49 = A. Eatoni, Jenm., in Journ. Bot. 1887, 98 (Fendler, 32). 12*. A. podophylla, Baker, in Journ. Bot. 1881, 202. New Granada, Kalbreyer ; habit and texture of Cyathea divergens. 16*. A. maerosora, Baker, in Trans. Linn. Soc. ser. 2, Bot. II, 288. Roraima, im Thurn. 16*. A. trichophlebia, Baker, n. sp. Frond ample, deltoid, tri- pinnatifid, moderately firm, green on both surfaces, glabrous above, furnished beneath with copious ovate bullate scales on the midrib of the pinnules, and all the veins beneath ciliated with large hairs ; rachises of pinnae pilose on both sides, especially above. Pinnae oblong-lanceolate, the largest 9-10 in. long, 2 J-3 in. broad. Pinnules sessile, lanceolate, 4-5 lines broad, cut half-way down to the midrib into oblong tertiary segments yV in. broad. Veins simple, 2-3-jugate. Sori medial. Paraguay, Balansa , 306 (Herb. De Candolle). Allied to A. atrovirens and jloribmida. 20*. A. pallescens, Sodiro, Recens. 20. Andes of Ecuador, Sodiro. Allied to A . paleolata , Mart. 37*. A. latevagans, Baker, in Journ. Bot. 1881, 203. New Granada, province of Antioquia, Kalbreyer , 1327. Very distinct and curious. 37*. A. hispida, Baker, in Journ. Bot. 1881, 202. Newr Granada, province of Antioquia, Kalbreyer , i56r. O 190 Baker . — A Summary of the new Ferns OLD WORLD SPECIES. 38*. Alsophila alata, Fourn., in Ann. Sc. Nat. s£r. 5, XVIII, 349. New Caledonia, Balansa , 1589. Not seen. 40*. A. dissitifolia, Baker, in Journ. Bot. 1886, 182. Fiji, Sir J. B. Thurston. 41. A. 1ST ovae-Caledoniae, Mett. Fournier, in Ann. Sc. Nat. ser. 5, XVIII, 349, refers this to Fournier a, but neither Mr. Wright nor I can find any trace of an indusium. Four- niera lepidotrieha, Fournier, loc. cit. New Caledonia, Balansa, 1592, not seen, is said to be extremely near to F. Novae-Caledoniae. 43*. A. woolsiana, F. Mull. Fragm. VIII, 179. Queensland. Near A. Leichardtiana. 47*. A. Hornei, Baker, in Journ. Bot. 1879, 293. Fiji, Horne. 47*. A. polyphlebia, Baker, in Journ. Linn. Soc. XV, 104. Arru Islands, Moseley (Challenger expedition). 48*. A. denticulata, Baker, in Journ. Bot. 1885, 102. Formosa, Hancock, 55. 56*. A. dubia, Beddome, in Journ. Bot. 1881, 1 t. 279 A. Perak and Borneo. Very near A. podophylla, Hook. 58*. A. rheosora, Baker, in Journ. Bot. 1890, 292. Tonquin, Balansa , 1803, 1861. 58*. A. formosana, Baker, n. sp. Frond ample, tripinnatifid, moderately firm, glabrous, green on both surfaces, rachis of pinnae naked, castaneous. Pinnae oblong-lanceolate, i-i-| ft. long, 5-6 in. broad. Pinnules sessile, lanceolate, nearly an inch broad, cut down to a broad wing into oblong lobes J- in. broad. Veins 6-8-jugate. Sori medial. Formosa, Hancock , 113. Near A. glabra, Hook. 58. A. glabra, Hook. I cannot separate A. vexans, Cesati, Fil. Recens. Born. 4. 59*. A. albo-setacea, Beddome, Handb. 16. Nicobar Isles, Kurz. 59*. A. Kingii, Clarke ; Beddome, Handb. 473. Perak. A. Bakeri, Zeiller, in Bull. Bot. Soc. France, XXXII, 71, is probably the same species. 59*. A. modesta, Baker, in Journ. Bot. 1880, 210. Sumatra, Bec- cari, 434. discovered or described since 1874. 19 1 59*. A. sikkimensis, Clarke & Baker, in Journ. Linn. Soc. XXIV. 409. Sikkim, Clarke. Probably a variety of A. ornata , with which links connecting it have just been found by Mr. Gam- mie, jun. 59*. A. obscura, Scortech. ; Beddome, in Journ. Bot. 1887, 321, tab. 278, fig. 2. Perak, Sc or tec him. Near A. comosa, Hook. 59*. A. triehodesma, Scortech. ; Beddome, in Journ. Bot. 1887, 321. Perak, Scortechini. 59*. A. Burbidgei, Baker, in Journ. Bot. 1879, 38. Borneo, Bar - hidge. 64*. A. castanea, Baker, in Journ. Bot. 1891, 3. North-west Mada- gascar, Last. 64*. A. simulans, Baker, in Journ. Bot. 1891, 3. North-west Mada- gascar, Last. 64*. A. vestita, Baker, in Journ. Linn. Soc. XV. 412. Madagascar, Pool. 64*. A. bullata, Baker, in Journ. Linn. Soc. XV, 412. Madagascar, Pool. 64. A. Baroni, Baker, in Journ. Linn. Soc. XXI, 455. Madagascar, Baron. In the second edition of the ‘ Synopsis Filicum,’ in 1874, about 200 tree-ferns are described as distinct species. Since that date upwards of eighty new ones have been found. Genus 8. Matonia R.Br. M. sarmentosa, Baker, in Journ. Linn. Soc. XXIV, 256 (see Plate XIV). Rachis slender, terete, with long internodes. Segments 3- 4 from each internode, linear, rigid, glabrous, simple or forked, 4- 5 in. long, i in. broad. Veins indistinct, simple, or forked. Indusium globose, rigid, superior, attached by a short central stipe, splitting by circumscissile dehiscence, so as to leave a patelliform persistent base. Sporangia 8-10 in a cluster, with a short stipe and incomplete vertical ring. Niah, Sarawak, Borneo, collected by Mr. Charles Hose in 1887, sent to Kew by the Bishop of Singapore and Sarawak. This is the most interesting novelty that has been found during the period which this paper covers. It has entirely the indusium and sporangia of the old well-known Matonia pecti- riata , on which this genus was established by Robert Brown, O 2, 192 Baker . — A Summary of the new Ferns but the habit of the plant is entirely different. Matonia ought clearly to form a tribe by itself, not to be united with the Cyatheaceae. HYMEN OPHYLLACEAE. Genus 16. Hymenophyllum Smith . 3*. H. Armstrongii, Kirk ; Baker, in Hook. Ic., tab. 161^ — H. me - lanocheilos , Colenso, in Trans. New Zeal. Instit. XVII, 255, is the same as Trichomanes Armstrongii , Baker, Syn. Fil. edit. 2, 465- 5*. H. Balfourii, Baker, n. sp. Rhizome filiform, wide-creeping. Stipe filiform, very short. Frond deltoid, glabrous, -J-J in. long, cut down to a narrow wing into 3-6 erecto-patent lobes, the upper simple, the lower forked. Sorus one to a frond, immersed in the end of a lobe ; indusium with a cuneate tube and orbi- cular lips. Bourbon, Balfour. Near the American H. ab- rupium, Hook. 8*. H. vincentinum, Baker, Ann. Bot. V, p. 164, Plate X. St. Vincent, H. H and G. W. Smith, communicated by F. Ducane Godman, F.R.S. 8*. H. terminale, Philippi, in Linnaea, XXXIII, 306. Chili. Near H. rarum . 10*. H. paniculiflorum, Presl ; V.D. B. Hymen. Jav. tab. 39. Japan. Appears to be a distinct species, intermediate between gracile and polyanthos. 14*. H. Thuidium, Harringt., in Journ. Linn. Soc. XVI, 23. Panay, Philippines, Steere. 15*. H. ooides, F. M. & Baker, in Journ. Bot. 1890, 103. High- lands of New Guinea, Sir W. Macgregor. 16*. H. dejectum, Baker, in Trans. Linn. Soc. N. S. Bot. II, 289. Summit of Mount Roraima, im Thurn. 18. H. polyanthos, Sw. I cannot separate H. lophocarpum, Colenso, in Trans. New Zeal. Instit. 1884, 233. 18*. H. villosum, Colenso; Kirk, in Trans. New Zeal. Instit. X, 393. Midway between polyanthos and demissum , more deltoid in outline than the former, with narrower segments and smaller sori. New Zealand. 18*. H. trichomanoides, Bailey, in Queensl. Flora, Suppl. 3, p. 90, discovered or described since 1874. 193 Summit of Bellenden Ker range. Not seen. Said to be like H. polyanthos in habit, with fruit between the types of Hymeno - phyllum and Trichomanes. 21*. H. austral©, Willd., Sp. Plant. V. 527 (1810), is an older name for this species than H. javanicum , Spreng. 21*. H. montanum, Kirk, in Trans. New Zeal. Instit. X, 394, tab. 21, fig. B. Lake Wakatipu, New Zealand. Like dwarf australe, with very jagged indusia. 21*. H. samoense, Baker, in Journ. Bot. 1876, 10. Samoa, Whitmee. 21*. H. streptophyllum, Fourn., in Ann. Sc. Nat. s6v. 5, XVIII, 2 66. New Caledonia, Balansa> 2708. Not seen. 22. H. demissum, Sw. I cannot separate H. megalocarpum, Colenso, in Trans. New Zeal. Instit. XV, 308. 22*. H. Baldwinii, Eaton; Baker, in Hook. Ic. tab. 1611. Sand- wich Islands, Miss E. S. Boyd. 27*. H. ereeto-alatum, Colenso, in Trans. New Zeal. Instit. 1878, 431. New Zealand. Not seen. Said to come in between dilatatum and pulcherrimum . 31*. H. pedicularifolium, Cesati, Fil. Polyn. Becc. 6. Rhizome filiform, wide-creeping. Frond oblong-rhomboid, nearly sessile, glabrous on the upper surface, densely ferrugineo-pilose be- neath, an inch long, cut down to a broadly-winged rachis into 5-6 pairs of pinnae, the upper simple, linear, the lower 2-3- lobed. Sori one each from the upper side of the upper pinnae near the base ; indusium oblong ; valves as long as the tube. Mountains of New Guinea, Beccari. 32*. H. Levingei, Clarke, in Trans. Linn. Soc. Bot. ser. 2, I, 439, tab. 49, fig. 3. Sikkim, alt. 7000 ft., Levinge. Very distinct. 32*. H. Boutoni, Baker, FI. Maurit. 462. Mauritius, Bouton. 34*. H. Poolii, Baker, in Hook. Ic. tab. 1619. Central Madagascar, Pool. 34*. H. Balansae, and humboldtianum, Fourn., in Ann. Sc. Nat. s6r. 5, XVIII, 265. New Caledonia, Balansa. Not seen. To be compared with H. ciliatum , Sw. 34*. H. paehydermicum, Cesati, Fil. Becc. Born. 8. Borneo, Beccari. Near ciliatum. 38*. H. rufescens, Kirk, in Trans. New Zeal. Instit. 1878, 457, tab. 19, fig. A. New Zealand, Field , Kirk. I am not sure that this is specifically distinct from H. sublilissimum , Kunze. 194 Baker . — A Summary of the new Ferns 46. Hymenophyllum sericeum, Sw. I cannot separ H. refron- descens, Sodiro, Recens. 2. 52*. H. tunbridgense, Sm. I cannot clearly separate H. pusillum, revolution, or pygmaeum, Colenso, New Zealand Ferns described in the Transactions of the New Zealand Institute for 1879-1880. 52*. H. brachyglossum, Cesati, Fil. Becc. Born. 7. Borneo, Beccari . Habit of a slender form of H. tunbridgense , but with round sori placed at the end of the segments. 52*. H. Henry i, Baker, in Journ. Bot. 1889, 176. West China; province of Hupeh, Dr. Henry , 5457. 52*. H. subflabellatum, Cesati, Fil. Becc. Born. 8. Sarawak, Borneo, Beccari. Fronds J in. long, broad ovate, almost flabellately bisect, the primary segments pinnatifid, with sori terminal or lateral on the lobes of the upper segments. 56*. H. oxyodon, Baker, in Journ. Bot. 1890, 262. Tonquin, Balansa , 1905. 63*. H. polyodon, Baker, in Journ. Linn. Soc. XX, 104. Admiralty Isles, Moseley (Challenger expedition). 67*. H. Houstonii, Jenm., in Journ. Bot. 1886, 42. Jamaica, Herb. Sloane. 67*. H. fraternum, Harringt., in Journ. Linn. Soc. XVI, 26. Panay, Philippines, Steere. 68*. H. Reinwardtii, Blume, V. D. B., Hymen. Jav. tab. 42. Appears to be a distinct species, near H. bivalve , Sw. Mount Sin- galan, Sumatra, Beccari. Genus 17. Trichomanes Linn . 7*. T. Hildebrandtii, Kuhn, in Reise Deck. Bot. 70. Johanna Island, Hildebrandt , 1856. 10*. T. Motleyi, V. D. B. I cannot separate T. beecarianum, Cesati, Fil. Becc. Born. 8, tab. 1, fig. 2, nor T. cognatum, Cesati, Fil. Becc. Polyn. 6. 10*. T. cultratum, Baker, in Journ. Bot. 1879, 293. Fiji, Horne. 10*. T. Wallii, Thwaites. Rhizome filiform, wide-creeping. Frond ovate or orbicular, ciliated, entire, J- in. long. Veins distinct, simple ; spurious venules o. Sorus solitary at the end of the distinct midrib. Indusium funnel-shaped, immersed, with a discovered or described since 1874. 195 broad entire collar-like border. Southern forests of Ceylon, Wall. 15*. T. Sayeri, F. M. & Baker. Rhizome wide-creeping. Stipe very short. Frond orbicular, or obovate-cuneate, in. long, deeply emarginate, with rounded apical lobes. Midrib distinct from base to apex; veins flabellate. Indusium solitary, terminal, stipitate; lips orbicular. Trinity Bay, Queensland, Sayer. 12*. T. labiatum, Jenm., in Gard. Chron. N. S. XXIV. 7. British Guiana, Jenman. 14*. T. setiferum, Jenm., in Journ. Bot. 1881, 52. Mountains of Jamaica, near Cinchona plantation, Nock. 20. T. mnscoid.es, Sw. I cannot separate T. yandimense, Bailey, Queensland Flora, 686. 20*. T. pinnatinervium, Jenm., in Gard. Chron. 1886, II, 787. British Guiana, Jenman. 23*. T. trinerve, Baker, FI. Maurit. 463. Mauritius, Lady Barkly. 27*. T. dichotomum, Philippi, in Bot. Zeit. 1856, 650. Chili, Philippi. 41*. T. ignobile, Cesati, Fil. Becc. Born. 9. Sarawak, Borneo, Beccari. Midway between hicorne and intramarginale. 44*. T. apicale, Fourn., in Ann. Sc. Nat. s6r. 5, XVIII, 257. New Caledonia, Vieillard. Not seen. 44*. T. spinnlosnm, Philippi, in Linnaea, XXX, 208. Chili, Philippi. 48*. T. Filieula, Bory. I cannot, from the description, separate T. johnstoniense, Bailey, Synops. Queensl. Plants, Suppl. 63- 49. T. pyxidifernm, L. I cannot separate T. barnardianum, Bailey, Synops. Queensl. Plants, Suppl. 3, 89, with figure. 49*. T. jungermannioides, Fourn. in Ann. Sc. Nat. s6r. 5, XVIII, 258. New Caledonia, Balansa , 1632. Not seen. 52*. T. Macgillivrayi, Baker, n. sp. Rhizome filiform, wide- creeping. Stipe slender, filiform, under an inch long. Frond oblong-lanceolate, bipinnatifid, glabrous, 1J-2 in. long; rachis winged down to the base ; pinnae crowded, oblong-lanceolate, sharply serrated ; secondary segments small, oblong. Sori one to a pinna, placed near the base on the upper side ; indu- sium with a campanulate tube, and sub-orbicular entire lips. Fiji, Macgillivray. Near the Bornean T. dcnliculaium , Baker. 1 96 Baker . — A Summary of the new Ferns 53*. Trichomanes veil o sum, R. Br. I cannot separate T. venus- tulum, Colenso, in Trans. New Zeal. Instit. XII, 366. 54. T. crispum, L. I can only separate as a variety T. digitatum, Sodiro, Recens. 4, non Swartz. It differs from the type by having the •indusium protruded entirely from the lamina. 61*. T. Hosei, Baker, in Journ. Linn. Soc. XXII. 223, tab. 12. Sarawak, Borneo, Bishop Hose. 61*. T. Beekeri, Krause; Philippi, in Linnaea, XXXIII. 305. Chili. Habit of Hymenophyllum dichotomum. 63*. T. Luersseni, F. M. ; Luerss., in Bot. Centralblatt, 1882, 440. Mountains of Aneiteum, G. Braithwaite. 70. T. rigidum, Sw. Surg. Halcro Johnston sends specimens con- necting with this species T. Hartii , Baker, in Gard. Chron. 1882, II. 680, collected at Sierra Leone by the late Dr. W. Hart. 71. T. apiifolium, Presl. Hymenophyllum? puellum, Cesati, Fil. Polyn. Becc. 6, collected by Beccari on the mountains of New Guinea, is probably a form of this species. POLYPODIACEAE. I should like to separate Hymenophyllaceae from Polypodiaceae as a distinct sub-order, and divide the latter into four tribes as follows : viz. (1) Indusium none (e. g. Acrosiichum, Polypodiuni) ; (2) Indusium formed only from the altered margin of the frond (e. g. Adiantum , Pteris) ; (3) Indusium formed in part from the altered margin of the frond, with an inner valve in addition (e. g. Dicksonia, Lmdsaya) ; and (4) Indusium truly dorsal (e. g. Aspidium, Asplenium). Genus 11. Woodsia R.Br. 4. W. lanosa, Hook., must be omitted. It is identical with Gymno- gramme Andersoni , Beddome, Fil. Brit. Ind. tab. 100. 6. W. insularis, Hance, must also be omitted. It is made up of a mixture of W. ilvensis and manchuriensis , as is shown by the type specimens, now at the British Museum. 6*. W. Haneockii, Baker, n. sp. Stipes densely tufted, 1-1 J in. long ; paleae ovate or lanceolate, pale brown. Frond lanceolate, bipinnatifid, 2-3 in. long, \ in. broad ; rachis slender, strami- neous, naked ; pinnae deltoid, J in. long, cuneate at the base, toothed on the outer edge ; lower lobes cuneate. Veins few, discovered or described since T874. 197 distinct. Sori 2 to the lower pinnae ; indusium small, with a fimbriate edge. Siao-wu-tai, Pekin, Hancock (Herb. Hance). Habit of dwarf forms of polystichoides ; sori of glabella ; stipe and rachis stramineous, not castaneous. 1 2. W. obtusa, Torrey. I cannot separate as a species W. Plum- merae, Lemmon, in Coulter, Bot. Gazette, VII. 6, from Southern Arizona. 12*. W. pusilla, Fourn., in Bull. Soc. Bot. France, 1880, 329. Mexico, Schaffner . Not seen. Genus 13. DlCKSONlA V Her it. 7*. D. fibrosa, Colenso. I cannot separate specifically D. sparman- niana, Colenso, in Trans. New Zeal. Instit. 1879, 363, nor D. microcarpa, Colenso, in Trans. New Zeal. Instit. 1888, 214. The Chatham Island Dicksonia is said to be intermediate between the Australian aniardica and New Zealand fibrosa . 7*. D. Lathamii, Moore, in Gard. Chron. 1885, vol. II, 584. A plant raised by Mr. W. G. Latham, in the Birmingham Botanic Garden. Intermediate between arborescens and antarclica. 10. D. squarrosa, Sw. I cannot separate specifically D. gracilis, Colenso, in Trans. New Zeal. Instit. 1882, 306. 11*. D. Baudouini, Fourn., in Ann. Sc. Nat. s6r. 5, t. 18, p. 347. New Caledonia, Baudouin. Allied to D. berteroana and De- plane hei. Not seen. 18*. D. ampla, Baker, in Journ. Linn. Soc. XXII. 223. Sarawak, Borneo, Bishop Hose. • 18*. D. Pearcei, Baker, n. sp. Rootstock not seen. Stipe long, naked, castaneous. Frond oblong-deltoid, tripinnate, a foot long, moderately firm, glabrous above, hairy on the ribs beneath ; lower pinnae the largest, subdeltoid ; pinnules sessile, lanceo- late, cut down to the rachis into oblong obtuse entire tertiary segments, in. broad. Veins of tertiary segments few, distinct; lower veinlets forked. Sori not more than one to each tertiary segment; indusium campanulate, coriaceous, with a truncate mouth. Eastern Andes of Ecuador, alt. 8000-9000 feet, Pearce , 251. Very distinct. 18*. D. pubescens, Baker, in Journ. Bot. 1881, 203. New Granada, province of Antioquia, alt. 6500 feet, Kalbreyer, 198 Baker . — A Summary of the new Ferns 18*. Dieksonia Sprucei, Baker, in Journ. Bot. 1877, 162. Andes of Ecuador, Spruce . 18*. D. vagans, Baker, in Journ. Bot. 1877, 162. Andes of Quito, Sodiro ; Andes of Peru, Barclay, 19*. D. incurvata, Baker, in Journ. Bot. 1879, 294. Fiji Islands, Horne , 971. 20*. D. antillensis, Jenman, in Journ. Bot. 1886, 267. Mountains of Jamaica, Morris , S her ring. Allied to the divided forms of D. cicutaria. 20*. D. glabrata, Cesati, Fil. Polyn. Becc. 6. Rootstock wide- creeping. Stipe 3-4 ft. long, stout, glossy, castaneous, naked, muricated. Fronds oblong-deltoid, 3-4 ft. long, glabrous, de- compound ; many lower pinnae lanceolate-deltoid, a foot long ; pinnules lanceolate-acuminate, tertiary segments free, lanceo- late-deltoid, produced on the upper side, obtusely toothed. Veinlets distant, erecto-patent. Indusium cup-shaped. New Guinea, Beccari. 21*. D. lambertiana, Remy, in C. Gay, FI. Chil. VI. 523. Root- stock not seen. Stipe long, stout, naked, stramineous. Frond lanceolate-deltoid, decompound, 1J-2 ft. long, glabrous on both surfaces ; rachis stramineous, without any hairs or scales ; pinnae crowded, lanceolate, lowest the largest, a foot long ; pinnules deltoid, cuneate-truncate on the lower side at the base, produced on the upper side ; tertiary segments lanceolate, deeply pinnatifid, in the largest pinnules in. long. Sori small, only one to each lobe ; indusium 2-lobed ; valves broader than long. Andes of Chili, Bonpland, Philippi , Ball. Most resembles D. davallioides in the cutting of the final divisions. 23*. D. gomphophylla, Baker, in Journ. Linn. Soc. XXII, 223. Borneo, mountains of Sarawak, alt. 2000 feet, Bishop Hose . 24. D. davallioides, var. Youngii, Moore. Rootstock epigaeous, stipes contiguous, an inch thick at the base. Australia. Has been cultivated at Kew for many years. 27. D. Elwesii, Baker. Better specimens, received from Mr. H. C. Levinge in 1885, show that this is not more than a marked variety of D. appendiculata , Wall. 29*. D. rhombifolia, Baker, in Journ. Bot. 1890, 105. New Guinea, near the summit of the Owen Stanley range, Sir W. Macgregor . discovered or described since 1874. 199 Genus 14. Deparia Hook . et Grev. 1 . D. prolifera, Hook. A plant lent to us by Sir F. Mueller, from Illawarra, New South Wales, will probably prove to be specifically distinct from the Hawaian type. It has narrow segments, and smaller less exserted sori. I believe that only a single specimen has been seen. 3. D. Godefroyi, Luerss., in Fil. Graef. 222, T. 19 (under Denn - staedtid). Fiji Isles, Graeffe , 54. Habit and cutting of Nephro- dium cicutarium ; veins forming copious areolae with branched free included veinlets. Genus 14*. Lecanopteris Blume . I now think this will have to stand as a distinct genus in the neighbourhood of Dicksonia , from which it differs by having the in- dusium formed from a single valve, and curious tuberous rootstock, with species as follows, viz. : — 1. L. carnosa, Blume, Fil. Jav. tab. 94 A. Perak and Philippine and Malay Isles. 2. L. pumila, Blume, Fil. Jav. tab. 94 B. Malay Isles. 3. L. Macleayii, Baker, n. sp. Rootstock not seen. Stipe short, naked. Frond lanceolate, glabrous, moderately firm, above a foot long, 4-5 in. broad, cut down to a narrowly-winged rachis with many linear obtuse crenate pinnae, in. broad. Sori distant, many to a pinnae ; indusium very small, orbicular, convex. Java, Macleay. 4. L. Curtisii, Baker, in Hook. leones, tab. 1607. Sumatra, Curtis . 5. Ii. deparioides, Baker, in Journ. Bot. 1881, 366. Davallia depa- rioides , Cesati, Fil. Becc. Born. 13, tab. 4, fig. 8. Rootstock tuberous, as in the other species, produced into short phyllo- podes articulated at the top. Stipe naked, substramineous, 6-8 in. long. Frond lanceolate, membranous, glabrous, simply pinnate, 1 \-2 ft. long, 3-4 in. broad ; rachis winged only at the top ; pinnae sessile, linear, obtuse, J in. broad, narrowed towards the base ; barren entire ; fertile crenate, with a sorus at the tip of each lobe. Venation of Phymatodes. Indusium as in the other species, consisting of a cup, formed from the edge of the frond, holding a small globose sorus. Borneo, Sarawak, Beccari . 200 Baker . — A Summary of the new Ferns Genus 18. Davallia Smith. Subgenus Humata. 4*. D. pinnatifida, Baker, in Journ. Bot. 1886, 257. Sarawak and Borneo, Bishop Hose. Intermediate between pectinata and pedata. 6. D. pedata, Smith. Further material appears to indicate that 7 D. alpina, Blume, 9 D. vestita, Blume, and 10D. Oumingii, Hook. (D. lepida , Presl) are not more than varieties of pedata. 9*. D. Tyermanni, Baker, in Hook. Ic. tab. 1620. Locality not West tropical Africa, as was supposed when the plant was first described by Moore from garden specimens, but Central China, where it has been collected by Maries , Everard, and Hancock. Subgenus Leucostegia. 13*. D. oligophlebia, Baker, in Journ. Bot. 1888, 323. Sarawak, Borneo, Bishop Hose. 16*. D. Kingii, Baker, in Hook. Ic. tab. 1622. Mountains of Java, H. O. Forhes, 657, 16*. D. nephrodioides, Baker, in Journ. Bot. 1 886, 257. Sarawak, Borneo, Bishop Hose. 17. D. Clarkei, Baker, in Hook. Ic. tab. 1625. I cannot separate specifically the Yunnan D, Delavayi, Beddome MSS. ; Clarke and Baker, in Journ. Linn. Soc. XXIV, 410. 17*. D. Hosei, Baker, in Journ. Bot. 1888, 323. Sarawak, Borneo, Bishop Hose. 22*. D. bipinnata, F. M., in Benth., FI. Austral. VII. 717 —Leptolepia hipinnata , Kuhn, Choetop. 28. Queensland, Walter Hilt and regathered lately at a height of 5000 feet by Sayer and Davidson. 22*. D. aspidioides, Baker; Leptolepia aspidioides , Mett. ; Kuhn, Choetop. 28, tab. 2, figs. 1-3. New Caledonia, Vieillard, 1612. 22*. D. Andersonii, Baker; Leptolepia Andersonii, Mett.; Kuhn, Choetop. 28, tab. 2, figs. 12-14. Honolulu, Anderson. 23*. D. athyriifolia, Baker, n. sp. Rootstock not seen ; stipe 2 ft. long, with a few lanceolate membranous dull brown paleae at the base. Frond oblong-deltoid, decompound, glabrous, 1 |-2 201 discovered or described since 18740 ft. long; lower pinnae oblong-lanceolate, 6-8 in. long; pinnules oblong-lanceolate, cut down to the rachis into oblong obtuse deeply pinnatifid tertiary segments, with oblong lobes. Veins of ultimate segments simple or forked. Sori generally solitary at the base of each final lobe ; indusium minute, membranous. Yunnan, Delavay . Near D. nodosa , Hook. 23*. D. Macgillivrayi, Baker; Leucostegia Macgillivrayi , Fourn., in Ann. Sc. Nat. §6r. 5, XVIII, 344. New Caledonia, Mac- gillivray. Not seen. 23*. D. maxima, Baker; Leucostegia maxima , Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 344. New Caledonia, Balansa, 1593. Not seen. 24*. D. cicutarioides, Baker, in Journ. Bot. 1890, 106. Mount Musgrave, New Guinea, Sir W. Macgregor. Subgenus Odontoloma. 28*. D. Hornei, Baker, FI. Maurit. 470. Seychelles, Horne. Subgenus Eudavallia. 34*. D. plumosa. Baker, in Journ. Bot. 1876, 10. Samoa, Whitmee. 36*. D. Graeffei, Luers. Fil. Graef. 211, tab. 18. Samoa, Powell , 168, Graeffe , 227. 37*. D. stenoloba, Baker, in Becc. Malesia, III. 35. Amboy na, Beccari. 39*. D. arctotheca, Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 339. New Caledonia, Balansa , 852. Not seen. 40. D. pallida, Mett. ; Baker, in Hook. Ic. tab. 1624. I cannot separate specifically D. beceariana, Cesati, Becc. Fil. Born. 14, tab. 3, fig. 6. 45*. D. Tasmani, Cheeseman; Field, Ferns New Zeal. 75, tab. 24, fig. 5. Kermadec Isles, Cheeseman. Near pyxidata and cana- riensis. One of the very few endemic plants of this small group of islands. 47*. D. Mariesii, Moore herb. Rootstock stout, wide-creeping ; paleae brownish, lanceolate from a dilated base. Stipe naked, shorter than the frond. Fronds deltoid, decompound, ever- green, moderately firm, glabrous, 4-6 in. long and broad; pinnae cut away on the lower side at the base ; lower much the largest, deltoid, produced on the lower side; pinnules 202 Baker.— A Summary of the new Ferns deltoid, cut away on the lower side at the base; final seg- ments short, linear, i -nerved. Sori distinctly intramarginal ; indusium small, campanulate. Mountains of Japan, Maries , in Hort. Veitch, 1878. To be compared with the varieties of bullata. 49*. Davallia Veitehii, Baker, in Journ. Bot. 1879, 39- Kina-balu, Borneo, alt. 6000-7000 ft. Burbidge. Subgenus Mierolepia. 50*. D. phanerophlebia, Baker, in Journ. Bot. 1890, 292. Ton- quin, Balansa , 118. 51*. D. Sloanei, Jenm., in Journ. Bot. 1886, 37. Jamaica, Herb . Sloane. Cutting of Dicksonia adiantoides, fructification of Davallia. 52. D. pinnata, Cav. I cannot separate specifically D. longipin- nula and D. intramarginalis, Cesati, Fil. Bee. New Guin. 7, gathered by Beccari on the mountains of New Guinea. 53*. D. triangularis, Baker, n. sp. Rootstock not seen. Stipe slender, fragile, naked, 6-8 in. long, brown towards the base, stra- mineous upwards. Frond deltoid, tripinnate, membranous, gla- brous, 4-5 in. long and broad ; lowest pinnae much the largest, oblong-deltoid; pinnules cut away on the lower side at the base ; final segments oblong, bi. broad. Veins pinnate in the final segments ; veinlets erecto-patent. Indusium cam- panulate, moderately firm, persistent. Yunnan, Delavay. Near D. Wil/ordii, Baker, which has now been found in Korea and Northern China. 54. D. hirsuta, Sw., has been found by Maries in Kiu Kiang and by Hancock at Chefoo and Ningpo. 57*. D. madagascariensis, Baker = Mierolepia Madagascar iensis , Moore, Ind. Fil. 318 — Davallia calobodon , Mett. = Dicksonia hypolepidoides , Baker, in Journ. Linn. Soc. XVI, 197. Has been gathered in Madagascar recently by Miss Helen Gilpin and Mr. J. T. Last. As regards fructification it stands on the boundary line between Dicksonia and Davallia. In cutting it closely resembles the common Indian D. rhomboidea , Wall. 58*. D. Kurzii, Clarke, in Trans. Linn. Soc. Bot. ser. 2, I, 446. Pegu, Kurz, 3236. Near D. platyphylla, Don. 62*. D, moluccana, Blume. I place as a variety, marked by its stout discovered or described since 1874. 203 muricated stipe, D. asperrima, Cesati, in Becc. Prosp. 6, gathered by Beccari in Amboina. 63*. D. philippinensis, Harringt., in Journ, Linn. Soc. XVI, 27. Mount Mahahuy, Philippines, Steere. Subgenus Stenoloma. 70*. D. odontolabia, Baker, in Journ. Bot. 1884, 140. North-east Madagascar, Humblot , 430. Near D. goudoiiana, Kunze. 71*. D. decomposita, Baker, in Journ. Bot. 1884, 141. North-east Madagascar, Humblot , 259. 71*. D. flabellifolia, Baker, in Journ. Linn. Soc. XV, 414. Central Madagascar, Pool, Genus 19. Cystopteris Bernh. 1. C. fragilis, Bernh. I can only separate as geographical varieties C. Novae Zealandiae, Armstrong, in Trans. New Zeal. Instit. 1880, 360, and the Australian Woodsia laetevirens, Prentice. 1*. C. japonica, Luers., in Engl. Jahrb. 1883, 363. Kiu-siu Archi- pelago, Tachiro . Not seen. 4*. C. moupinensis, Franch., PI. David. 149. Moupine, Tibet, David. Not seen. Perhaps identical with a plant collected twice by Mr. H. E. James , in his recent journey between Mukden and Kirin, which comes near the very rare European C. sudetica , A. Br. & Milde. Genus 20. Lindsaya Dry and. Subgenus Eulindsaya. 1. L. linearis, Sw. I can only separate as a slight variety L. trilobata, Colenso, in Trans. New Zeal. Instit. 1883, 345. 1*. L. incisa, Prentice, in Journ. Bot. 1873, 295. Queensland, Prentice , Bailey. 1*. L. dimorp ha, Bailey, Queensland Ferns, 19. L. heterophylla, Prentice, in Journ. Bot. 1873, 295, non Dryand. Queensland, Prentice , Bailey. This and the last are very near to L. linearis. 4*. Ii. plicata, Baker, in Journ. Linn. Soc. XXV, 350. North- east Madagascar, Baron , 5887, Last. 204 Baker . — A Summary of the new Ferns 5. Lindsaya ooncinna, J. Sm. Not distinct specifically from L. cultrata , Sw. 5*. L. jamesonioides, Baker, in Journ. Bot. 1879, 39; Hook. Ic. tab. 1626. Kina-balu, Borneo, Burbidge. 7*. L. oxyphylla, Baker, in Journ. Bot. 1891, 3. North-east Madagascar, Last. 7*. L. erispa, Baker, in Journ. Bot. 1879, 39 ; Hook. Ic. tab. 1627. Borneo, Burbidge. 13*. L. leptophylla, Baker, in Journ. Bot. 1884, 141 ; Hook. Ic. tab. 1628. North-east Madagascar, Humblot , 495. 16*. L. madagascariensis, Baker, in Journ. Linn. Soc. XVI, 198 ; Hook. Ic. tab. 1629. Madagascar. This runs down into a curious odontolomoid form, which bears the same relation to the type that Davallia schizophylla (Synopsis, edit. 2, p. 468) bears to LLndsaya tenera. 16*. L. gomphophylla, Baker, n. sp. Rootstock not seen. Stipe produced, naked, castaneous. Frond deltoid, rigid, glabrous, J-ft. long, simply pinnate in the upper, bipinnate in the lower half; lower pinnae much the largest. Final seg- ments orbicular-cuneate, J-in. broad, deeply crenate round the outer edge, cuneate in the lower half. Veins simple, flabellate. Sori interrupted. Indusium narrow, rigid, persistent. Borneo, Sir Hugh Low. Allied to the New Caledonian L. nervosa, Mett. 17*. L. prolongata, Fourn., in Ann. Sc. Nat. sdr. 5, XVIII, 334. New Caledonia, Balansa, 1602. Not seen. 24*. L. tricrenata, Baker, in Journ. Bot. 1890, 106. Mount Mus- grave, New Guinea, Sir W. Macgregor. Subgenus Isoloma. 28*. Ii. indurata, Baker, in Journ. Bot. 1888, 324. Sarawak, Borneo, Bishop Hose. 31*. L. flavicans, Mett. ; Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 334. New Caledonia. Not seen. 31*. Xj. exilis, Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 335. New Caledonia, Vieillard, Balansa. Not seen. 31*. Xj. eampylophylla, Fourn., in Ann. Sc. Nat. s£r. 5, XVIII, 335. New Caledonia, Balansa, 854. Not seen. 31*. Xj. Balansae, Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 335. New Caledonia, Balansa, 1652. Not seen. discovered or described since 1874. 205 31*. I*, mediocris, Fourn., in Ann. Sc. Nat. sdr. 5, XVIII, 336. New Caledonia, Balansa. Not seen. 32*. L. viridis, Colenso, Fil. Nov. New Zeal. 14. New Zealand. Allied to L. microphylla , Sw., from which it differs by much closer regularly cuneate final segments, and sub-davallioid sori. Subgenus Synaphlebium. 37. L. lobata, Poir. I cannot separate specifically L. ambigens, Cesati, Fil. Becc. Polyn. Subgenus Diellia. The late Dr. Hillebrand, in his recently-published Flora of the Hawaian Islands, has fully re-described the species and varieties of this curious subgenus, which is peculiar to the Sandwich Islands. To the species in our Synopsis Filicum he adds the following, viz : — Ii. centifolia, Hillebr. p. 621. L. laciniata, Hillebr. p. 621, with 2 varietes. L. Alexandri, Hillebr. p. 622, with 3 varieties. L. Knudsenii, Hillebr. p. 623, with a variety. Genus 21. Adiantum Linn. Kuhn, in Jahrb. Berlin. Bot. Gart. vol. I. p. 337, has published a valuable monograph of this genus. He characterises briefly 113 species, many of which are dealt with as varieties in the Synopsis Filicum. He proposes two subgenera, viz.— (1) Euadiantum , spo- rangia confined to the veins ; and (2) Adiantellum, sporangia occupying the intervening parenchyma as well as the veins. 1. A reniforme, L. Besides the type, which inhabits Madeira and the Canaries, and var. asarifolium , Willd., which inhabits Mauritius and Bourbon, a third subspecies, crenatum. Baker, has lately been found by Mr. J. T. Last in the North-East of Madagascar. It differs from the others by its more distant sori and crenate edge of the frond. 3*. A. Balfourii, Baker, in Hook. Ic. tab. 1630. Socotra, Balfour. Differs from all the forms of lunulatum by its equilateral shortly-petiolate pinnae. 3*. A. Balansae, Baker, in Journ. Bot. 1890, 262. Tonquin, Balansa} 134. Near the African A. Metlenii, Kuhn. P 20 6 Baker,— A Summary of the nezv Ferns 3*. Adi ant um Peareei, Philippi, in Linnaea, XXXIII, 304. Andes of Chili, Pearce. Near A. pumilum, Sw. Not seen. 3*. A. Gravesii, Hance, in Journ. Bot. 1875, 197 = A. Mariesii, Baker, in Gard. Chron., N. S. XIV, 494. Central China, Lamont , Maries . Simply pinnate frond like dwarf lunulatum ; segments like those of monochlamys. 3*. A. ruizianum, Klotzsch. ; Hook. Sp. Fil. II, 10. Stipe naked, castaneous, 6-9 in. long. Frond lanceolate, simply pinnate, 6-8 in. long, 2-2 1 in. broad, firm, glabrous. Pinnae 1-1J in. broad ; end one deltoid ; side ones suborbicular, broader than long ; lower margin straight ; all the rest crenate ; petiole of lower pinnae J-i in. long. Sori orbicular, placed all round the pinnae except the base. Peru, Pavon. Near A. grossum, Mett., but pinnae smaller, with longer stalks, and sori and indusia orbicular. Described from a type specimen kindly lent by Mr. H. C. Levinge. 5*. A. amelianum, Glaziou; Baker, in Journ. Bot. 1882, 309. South Brazil, Glaziou , 12,280. Doubtfully distinct from A. rhizophytum , Schrad. 7*. A. Kaulfussii, Willd. and 8, A. obliquum, Willd. are best considered as two varieties of A . platyphyllum , Sw. 12*. A. Glaziovii, Baker, in Journ. Bot. 1882, 309. South Brazil, Glaziou , 13,345. Intermediate between intermedium and obtusum . 13*. A. Steerei, Harringt., in Journ. Linn. Soc. XVI, 34. Pona Cocha, Andes of Peru, Sleere. 15. A. diapbanum, Blume. A. heteromorphum, Colenso ; Field, Ferns New Zeal. 80, is a variety, and I cannot separate specifically A. polymorphum and A. tuberosum, Colenso, in Trans. New Zeal. Instit. 1888, 215-217. 15*. A. monosorum, Baker, in Hook. Ic. tab. 1633. Solomon Isles, Herb. Macleay. 16*. A. Hosei, Baker, in Journ. Bot. 1888, 324. Borneo; pendu- lous on limestone cliffs, Sarawak, Bishop Hose. Near affine. 16. A. affine, Willd., var. intermedium, Benth., FI. Austral. VII, 725, Queensland and N. S. Wales, differs from the New Zealand type by its transversely oblong sori ; var. chathamicum , Field, Ferns New Zeal. 81, Chatham Island, is less compound than discovered or described since 1874. 207 the type with longer final segments. See also var. hetero - phyllum , Colenso, in Trans. New Zeal. Instit. 1888, p. 218. 16*. A. Hornei, Baker, in Journ. Bot. 1879, 294. Fiji, Horne , 560. Near affine. 22*. A. dioganum, Glaziou ; Baker, in Journ. Bot. 1882, 310. South Brazil, Glaziou. Between cristatum and villosum. 27*. A. Novae-Caledoniae, Keyserl. Monogr. Adiant. 4. New Caledonia. Introduced into cultivation in 1883, by Messrs. W. and J. Birkenhead. Near A.fulvum. 31*. A. pilosum, Baker, n. sp. Stipe 2 ft. long, black, glossy, and naked below the top. Frond deltoid, bipinnate, a foot long and broad; rachises densely pilose. Segments crowded, rhomboid, entire on the lower and inner, toothed on the upper and outer edges, the central an inch long, \ in. broad. Sori round, one placed at the tip of each lobe on the upper margin of the segments. Indusia round, persistent, f in. diam. New Granada, Kalbreyer, 95 6. Near A. tetraphyllum , Willd. 41. A. Capillus-veneris, L. A. Fergusoni, Moore, in Gard. Chron. 1884, II, 360; and A. Mairisii, Moore, in Gard. Chron. 1885, II, 294 (A. Roperi , Hort.), are forms of garden origin, probably derived from this species. 41*. A. Levingei, Baker, n. sp. Stipe slender, castaneous, \ ft. long. Frond deltoid, 2-3-pinnate, glabrous, 8-12 in. long; lower pinnae much the largest. Final segments : terminal cuneate, in. broad, deeply 2-3-lobed on the upper margin, with a sorus at the base of a sinus in the centre of each lobe ; lateral segments subrhomboid, distinctly petioled. Indusium firm, glabrous, orbicular-reniform, in. diam. Sikkim, Chingtang, alt. 3000 ft., Levinge. Cutting of Capillus-veneris ; sori and indusium of venustum. 41*. A. Sehaffneri, Fourn., in Bull. Soc. Bot. France, 1880, 328. Mexico, Schaffner. Not seen. 42*. A. hians, Moore, in Gard. Chron. 1887, I, 41. Stipe elongate, slender, castaneous. Frond membranous, deltoid, tripinnate, glabrous, a foot long. End segments cuneate ; lateral rhom- boid, in. broad, deeply lobed on the outer edge. Sori only 1-2 to a segment. Sinus deep. Indusium large, reni- form. New Caledonia and Fiji, Herbert. 42*. A. Williamsii, Moore, in Gard. Chron. 1878, II, 44, fig. 4. P 2, 2o8 Baker . — A Summary of the new Ferns Habit slightly sarmentose. Rachises brown-black, quite glabrous. Frond deltoid, tripinnate, 1J-2 ft. long, tinged with sulphur when young. Pinnae deltoid, the lowest the longest. Rachis flexuose upwards. Final segments J-J in. broad, all distinctly stalked, the end one cuneate, the lower side ones rounded or nearly truncate at the base. Sori 3-5 to a segment, roundish or broader than deep. Andes of Peru, alt. 12,000 ft. Near aethiopicum . 42*. Adiantmn neo-guineense, Moore, in Gard. Chron. 1887, 1, 12. Stipe naked, castaneous, 6-8 in. long. Frond deltoid, tripinnate, glabrous, above a foot long and broad. Rachises very slender, glabrous, nearly black. End segments cuneate ; lateral tra- pezoid, \ in. long, cuneate. Sori orbicular, 3-4 to a segment, placed in deep sinuses. New Guinea, Goldie . Recedes from aethiopicum in the direction of tenerum . 43. A. excisum, Kunze. A. Pacotti, Hort. and A. Weigandii, Moore, in Gard. Chron. 1883, II, 748, are forms of garden origin, probably derived from this species. 45*. A. Wagneri, Mett. (A. decorum , Moore). A. elegans, Moore, in Gard. Chron. 1886, I, 200; A. cyclosorum, Moore, in Gard. Chron. 1887, I, 547; and A. Oweni, Moore, in Gard. Chron. 1887, IIO> are forms of garden origin nearly allied to this species. 46. A. tenerum, Sw. A. Lathomi, Gheisbreghtii, Scutum, Far- leyense, Victoriae, Bausei, rhodophyllum, and Princeps, of gardens, are probably all of them derived from this species. 46*. A. Collisii, Moore, in Gard. Chron. 1886, I, 681. A form of garden origin which appears to be intermediate between tenerum and cuneatum. 47. A. cuneatum, L. & F. A. festum, fragrantissimum, Wal- toni, Dadsii, aemulum, gracillimum, and mundulum, of Moore, appear to be varieties of this species. 47*. A. bellum, Moore, in Gard. Chron. 1879, I, 172, Fig. 24. Bermuda, Lefroy , Moseley. Intermediate between cuneatum and aethiopicum. 47*. A. Paradiseae, Baker, in Gard. Chron. 1889, II, 558. Bedford, Cape Colony, Miss Paradise. 48*. A. Cooperi, Baker, in Journ. Bot. 1887, 25. Costa Rica, Cooper . Near glaucophyllumy Hook. discovered or described since 1874. 209 50*. A. Wattii. Baker, in Journ. Linn. Soc. XVIII, 381, tab. 14 a, Figs. 1-2. Chumba, Watt. 50*. A. Davidi, Franchet, PI. David. II, 150. Moupine, Tibet, Pere David. 51*. A. Faberi, Baker, in Journ. Bot. 1888, 225. Mt. Omei, West China, alt. 3000 ft., Faber , 1033. 51*. A. Senae, Baker, in Journ. Bot. 1885, 217. South Brazil, Glaziou , 15,723. Intermediate between tremulum and the small forms of cuneahim. 51*. A. Boborowskii, Maxim. Mel. Biol. XI, 867. West China ; Kansu, Przewalski. Allied to monochlamys and Gravesii. 56*. A. Oatesii, Baker, in Oates, Matebeleland, App. with Figure. Matebeleland, Oates. Very near pedatum. 57. A. hispidulum, Sw. A. Birkenheadii , Moore, in Gard. Chron. 1886, I, 648. appears to be a variety of this species. 58*. A. rigidum, Fourn., in Ann. Sc. Nat. s^r. 5, XVIII, 329. New Caledonia, Balansa, 50, 2689. Not seen. 58*. A. stenochlamys, Baker, n. sp. Stipe long, naked, wiry, nearly black. Frond pedate, tripinnate, deltoid, firm, glabrous, 6-9 in. long and broad. Final segments : terminal cuneate, J-f in. broad, shallowly lobed, and crenate round the upper half; lateral subrhomboid, shortly petioled, little longer than broad, with the inner edge indexed so that it is imbricated over the rachis ; upper and outer edge shallowly lobed and crenate. Sori 6-8 to a fully-developed segment, ^ in. long. Indusium firm, narrow. British North Borneo ; Kudat, Dr. Fraser . Pulo Gaya, Sir H. Low. Genus 23. Lonchitis Linn. 1*. L. Polypus, Baker, in Journ. Linn. Soc. XV, 414. Madagascar, Pool, Hildebrandt. Genus 24. Hypolepis Bernh , 13*. H. meifolia, Baker ; Cheilanthes meifolia , Eaton, in Proc. Amer, Acad. XVII, 185. Mexico, Parry $ Palmer. Closely allied to H. calif ornica. 2io Baker . — A Summary of the new Ferns Genus 25. Cheilanthes Sw. Subgenus Adiantopsis. 1*. C. Fordii, Baker, in Journ. Bot. 1879, 304. Canton, Ford. 6*. C. Duthiei, Baker, n. sp. Stipes densely tufted, castaneous, glabrous, i-ij in. long, with a few paleae towards the base. Frond oblong-deltoid, membranous, glabrous, 2 in. long, green on both surfaces. Pinnae oblong-deltoid, sessile : lowest the largest, produced on the lower side. Pinnules oblong, J— j. in, broad. Sori placed all round the edge of the pinnules, usually orbicular, rarely confluent. Indusium grey, glabrous, orbicular-reniform, persistent. British Garwhal, Duthie, 5144. Cutting of C. subvillosa , but indusium of this subgenus. 11. C. Schimperi, Kunze. Has been gathered in the Usugura Mountains by the late Bishop Hannington and in the Shird Highlands by Mr. J. T. Last. Known before only in Abyssinia. 12*. C. Reesii, Jenm., in Journ. Bot. 1886, 267. Jamaica, Rev. J. L. Rees. Cutting of C. microphylla ; sori and indusium of this subgenus. 13*. C. madagascariensis, Baker, in Journ. Linn. Soc. XVI, 198. Madagascar, Miss Helen Gilpin. Subgenus Eucheilanthes. 15*. C. depauperata, Baker, n. sp. Stipes densely tufted, wiry, castaneous, naked, 3-4 in. long. Frond lanceolate, bipinnate, rigid, 4-6 in. long, in. broad, green and glabrous on the upper surface; rachis castaneous, scabrous, viscose. Pinnae numerous, small, deltoid, with many linear lobes with strongly recurved edges. Sori hidden by the recurved margin. Cape Colony ; Central Karroo region, Sir H. Barkly, Bolus . 16*. C. moncloviensis, Baker, n. sp. Stipes naked, tufted, cas- taneous, 3-4 in. long. Frond deltoid, tripinnate, glabrous, 2-3 in. long, moderately firm, green and naked on both sides. Lower pinnae the largest, deltoid ; rachises castaneous, furnished with many ovate or lanceolate pale membranous paleae. Final segments obovate-cuneate, xV“tV in- broad. Indusium broad, rigid, glabrous. North Mexico; Coahuila 21 I discovered or described since 1874. and Nuevo Leon, 1880, Palmer , 1378. Near C. fragrans, Sw. 17. C. arabica, Decaisne. Somali-land, Hildebrandt , 1489. 18*. C. Cooperae, Eaton, Ferns North Amer. 7, tab. 2, fig. 1. Cali- fornia and North Mexico. 18*. C. Streetiae, Baker; Notochlaena Streetiae , Baker, in Journ. Linn. Soc. XVI, 204. Madagascar, Mrs. Street. Habit and texture of the small forms of Hypolepis bergiana . 1 9*. C. heterotrieha, Anders., in Eugen. Reise, 40. Charles Island, Galapagos group. Near C. Macleami, Hook. Not seen. 22*. C. Delavayi, Baker, n. sp. Stipes tufted, hairy, castaneous, 5-6 in. long. Frond deltoid or oblong-deltoid, tripinnatifid, \ ft. long, 2-3 in. broad, moderately firm, green on both sur- faces, finely pubescent. Lower pinnae the largest, deltoid, petioled. Pinnules deltoid, |-f in. broad, cut down nearly to the rachis into contiguous oblong lobes. Indusium continuous, rigid, drab-brown, crenate. Yunnan, Delavay. 23*. C. trichophylla, Baker, n. sp. Stipes tufted, pubescent, brown, 4-5 in. long. Frond oblong-lanceolate, tripinnate, moderately firm, densely pilose, a foot long, 3-4 in. broad ; main rachis flexuose. Pinnae deltoid or oblong-deltoid, the longest 2 in. long, mostly patent or even rather deflexed; final segments linear-oblong, J-J- in. long. Indusium broad, pale, persistent. Yunnan, Delavay. 24*. C. Pringlei, Davenport, in Bull. Torrey Club, 1883, 61, tab. 34. Mountains of South-East Arizona, Pringle. 24*. C. longipila, Baker, n. sp. Stipes tufted, wiry, brown, 1-4 in. long, densely clothed with long soft white hairs, as are the rachis and lamina. Fronds oblong-lanceolate, tripinnate, 3-4 in. long. Pinnae lanceolate-deltoid, rather ascending, more produced on the lower side. Ultimate segments oblong, crenate-pinnatifid, subbullate, under \ line broad. Sori round, very minute, finally confluent. Central Mexico, 6000-8000 ft., Parry Sf Palmer , 989. Near C. viscosa, Kaulf., but hairs longer, not glandular, and fronds oblong-lanceolate, not deltoid. 26*. C. Cielandi, F. M. & Tate, in Trans. Roy. Soc. South Austral. 1887. South Australia: west of Spencer gulf. Habit of Pellaea pilosa and Bojeri. Not seen. 212 Baker . — A Summary of the new Ferns 27*. Cheilanthes Thwaitesii, Mett. An earlier name is C. laxa , Moore, Ind. Fil. 245. 28*. C. patula, Baker, in Journ. Bot. 1888, 225. Western China, Dr. A. Henry , 3998. Near C. subvillosa , Hook. 28*. C. Krameri, Franch. et Savat., Enum. Jap. Ill, 619. Japan. Near C. subillosa. Not seen. 29*. C. albomarginata, Clarke, in Trans. Linn. Soc. Bot. ser. 2, I, 456, tab. 52. Eastern Himalayas. Cutting of C.farinosa, but denuded, with white-edged paleae. Beddome now places C. Dalhousiae , Hook, as a variety of farinosa . 34. C. tenuifolia, Sw. It seems impossible to draw any definite line of demarcation between tenuifolia and Sieberi. I cannot separate specifically C. Kirkii, Armst., in Trans. New Zeal. Instit. 1880, 36, non Hook.; C. javensis, Moore, Ind. Fil. 244 ; Pteris alpina, Field, Ferns New Zeal. 97, tab. 98, fig. 3 ; nor C. exilis, Moore & Houlston. 34*. C. viseida, Davenport, in Bull. Torrey Club, VI, 192. Sierra Nevada, California. Subgenus Physapteris. 35*. C. flexuosissima, Baker, n. sp. Stipes densely tufted, cas- taneous, naked, \ ft. long. Frond deltoid, decompound, 3-4 in. long, fragile, membranous, glandulose-puberulent on both surfaces. Segments round or obovate, bullate, J line broad, flabellately toothed in the upper half. Sori placed all round the segments except the base. Indusium continuous, scariose. South Brazil, Glaziou , 7482. 36*. C. recurvata, Baker, in Journ. Bot. 1878, 299. Paraguay, Balansa , 35 . Near C. regnelliana , Mett. 37*. C. Bolusii, Baker, in Hook. Ic. tab. 1636. Cape Colony : South Western province, Bolus , 2801. Near C. induta , but 4- pinnatifid, with a black rachis and stipe and small round bullate segments. 38*. C. Parishii, Davenport, in Bull. Torrey Club, VIII (1881), 61, tab. 8. California, W. P. Parish . 43*. C. albida, Baker, n. sp. Stipes tufted, wiry, slender, slightly scaly, 2-5 in. long. Frond oblong-lanceolate or oblong-deltoid, tripinnate, 2-3 in. long, densely white-hairy on both surfaces, with densely imbricated bright brown paleae on the midribs of 213 discovered or described since 1874. the pinnae and pinnules beneath. Pinnae lanceolate-deltoid, the central |-f in. long; tertiary segments small, round, bullate. Central Mexico, Parry § P 'aimer , 999. 43*. C. Clevelandii, Eaton, Ferns North Amer. 89, tab. 12, fig. 2. California. 43*. C. cinnamomea, Eaton, in Proc. Amer. Acad. XVII, 186. Myriopteris rufa , Fde. Mexico, Schaffner , 91. 47*. C. intermedia, Baker; Myriopteris intermedia , Fourn., in Bull. Soc. Bot. France, 1880, 328. Mexico, Schaffner. 48*. C. peruviana, Baker; Plecosorus peruvianas, Fee, Gen. Fil. 195. Stipes brown, tufted, nearly naked, 6-8 in. long. Frond oblong-lanceolate, bipinnate, a foot long, subrigid, green and glabrous on the upper surface, densely paleaceous beneath. Pinnae many, lanceolate, 1J-2 in. long, cut down to the midrib into oblong crenate pinnules with much indexed edges. Sori filling up nearly the whole under surface of pinnules. Peru, Pavon. Very distinct. 53. C. farinosa, Kaulf. For an account of the Indian forms see Mr. H. F. Blanford’s paper on the Silver Ferns of Simla, read before the Simla Natural History Society, June 25, 1886. I cannot separate specifically C. anceps and C. grisea, there described, nor from the descriptions, the Mexican Aleuritopteris Sehaff- neri, Fourn. in Bull. Soc. Bot. France, 1888, 328; nor the Japanese C. Brandtii, Franch. et Savat. Enum. Jap. II, 620. 53*. C. Palmeri, Eaton, in Proc. Amer. Acad. XXII, 464. Jalisco, Mexico, Palmer , 223. Genus 30. Pellaea Link. 12*. P. eambodiensis, Baker, n. sp. Stipes densely tufted, slender, castaneous, naked. Frond glabrous, chartaceous, lanceolate- deltoid, 2-3 in. long, an inch broad, bipinnatifid or bipinnate. Pinnae 5-6-jugate below the pinnatifid apex, the lowest the longest, produced on the lower side, subdeltoid, broadly obtusely lobed. Veins free, branched. Indusium pale, gla- brous. Cambodia, Godefroy-Lebeuf, 860. Habit of P.nitidular much less compound. 13*. P. Biedelii, Baker, n. sp. Habit of P. burkeana. Frond rigid, bipinnate. Segments linear, with enrolled margins. Central Brazil, Riedel. 214 Baker— A Summary of the new Ferns 15. Pellaea ternifolia, Fde. West Indies, St. Domingo, Baron Eggers . I cannot separate specifically Cheilanthes weddel- liana, Moore, Ind. Fil. 257. 16*. P. Pringlei, Davenport, in Herb. Pringle Jalisco, 2591. Frond simply pinnate ; lower pinnae petioled, hastate. North Mexico. 17*. P. laneifolia, Baker, n. sp. Stipes densely tufted, castaneous, 2-3 in. long, with a few minute linear paleae near the base. Frond lanceolate, bipinnate, membranous, glabrous, 4-5 in. long, narrowed from the middle both ways. Rachis naked, castaneous. Central pinnae the largest, sessile, lanceolate, cut down nearly or quite to the rachis into 2-3-jugate, adnate, ovate-deltoid patent lobes, i-ij lin. broad; lower pinnae distant, dwarfed. Indusium very broad, green, glabrous. Namaqualand, Sir H. Barkly. Differs from profusa by its naked rachis and very broad indusium. 22*. P. Kitchingii, Baker, in Journ. Bot. 1880, 327 ; Hook. Ic. tab. 1639. Central Madagascar, Kitching. 24*. P. fumariaefolia, Philippi. Stipes tufted, slender, naked, 3-4 in. long, green above the castaneous base. Frond oblong, decompound, thick, green, glabrous, 2-3 in. long ; sterile more compound than the fertile. Lower pinnae the largest, petioled, deltoid. Final segments short, linear, 1 -nerved. Fertile frond less compound ; final segments linear-oblong, in. long. Sori filling the whole under surface of the segments. Indusium broad, continuous, rigid, glabrous. Araucania, Philippi. Habit of Cryptogramme crispa. 28*. P. namaquensis, Baker, n. sp. Stipes densely tufted, cas- taneous, 2-3 in. long, clothed with distinct spreading linear paleae. Frond deltoid, tripinnatifid, bright green, glabrous, 2-3 in. long; rachis castaneous, with a few minute paleae. Lowest pinnae much the largest, deltoid, stalked, J in. broad, its pinnules cut down nearly to the rachis into a few oblong lobes. Indusium narrow, green, membranous, glabrous. Namaqualand, Sir H. Barkly. Between involuta and conso- brina. 35*. P. integricuspis, Fourn., in Ann. Sc. Nat. ser. 5, XVIII, 324. New Caledonia, Balansa , 824. Not seen. To be compared with P.falcata. discovered or described since 1874. 215 38*. P. tripinnata, Baker, ill Journ. Linn. Soc. XXV, 350. Mada- gascar, Baron, 5674. 40*. P. crispatula, Baker, n. sp. Stipes very slender, densely tufted, castaneous, fragile, naked, 1-2 in. long. Basal paleae lanceolate, bright brown, minute. Fronds simple, lanceolate, glabrous, 2-2J in. long, J in. broad, narrowed gradually to the point, generally cordate at the base, with small rounded contiguous lobes. Veins very distinct, forming 2-3 rows of areolae between the midrib and edge, without any included veinlets. Sori placed all round the margin of the frond, at first globose, finally confluent. Indusium very narrow, obscure. South Brazil, Glaziou , 14,405. Habit of Pteris sagittifolia . Sori and indusium very different. Genus 31. Pteris Linn . Subgenus Eupteris. 1*. P. phanerophlebia, Baker, in Journ. Bot. 1881, 367 ; Hook. Ic. tab. 1610. Madagascar, Curtis, Baron , Humblot , Last. Habit of P. sagittifolia , Raddi, but veins free. 1*. P. quinquelobata, Baker; Pellaea quinquelobata, Fee; Prantl, in Engler’s Jahrb. 1882, 422. South Brazil, Glaziou, 7011. Habit of less divided forms of P. palmata. Frond thick, deltoid, 3-5-lobed. 1*. P. platysora, Baker, in Journ. Bot. 1880, 21 1. Sumatra, Beccari. 3*. P. vitiensis, Baker, in Journ. Bot. 1879, 295. Fiji, Horne , 718. 4. P. cretiea, L. P. Mayi, Hort. is a crested variegated form. I cannot separate specifically the New Zealand P. lomarioides, Colenso, in Trans. New Zeal. Instil. 1880, 380; Field, Ferns New Zeal. 91, tab. 25, Fig. 4. P. treacheriana, Baker, in Journ. Bot. 1879, T. 5, is identical with P. melanocaulon, Fde. 5. P. pellucida, Presl. P. commutata, Kuhn, in Reise Decken Bot. 20, is apparently a variety of pellucida, with veins casually anastomosing. 5*. P. papuana, Cesati, Fil. Bee. Polyn. 3, 7. Rhizome repent, as thick as a man’s thumb, tomentose, with minute brown subu- late paleae. Stipe a foot long, naked, dark purplish brown. 2i6 Baker . — ^ Summary of the new Ferns Fronds oblong-lanceolate, simply pinnate, glossy, glabrous, coriaceous, 2-3 ft. long. Pinnae linear, 6-7 in. long, £ in. broad, very acuminate, obscurely serrulate at the tip, the upper single, the lower 3-4-jugate. Veins subpatent, very fine, and close. Mountains of New Guinea, Beccari. P. pellu- cida, Cesati, loc. cit., is a more luxuriant form of the same species. 6*. Pteris sumatrana, Baker, in Journ. Bot. 1881, 367. Sumatra, Curtis. Near P. hooker iana and serrulata. 7. P. dactylina, Hook., has been found recently in Szechwan by Faber , and Yunnan by Delavay. 9. P. serrulata, L. fil. Has been found lately in Alabama and Guadeloupe. Can it be a mere variety of cretica ? 10. P. ensiformis, Burm. P. Vietoriae, Hort. Bull., is a beautiful variety of this species, with fronds variegated with white. 10*. P. Balansae, Fourn., in Ann. Sc. Nat. sdr. 5, XVIII, 320. New Caledonia, Balansa} 797. Not seen. 10*. P. polymorpha, Fourn., in Ann. Sc. Nat. sdr. 5, XVIII, 320. New Caledonia, Balansa, 831, 2 686. Not seen. 12*. P. inaequalis, Baker, in Journ. Bot. 1875, 199. China and Japan. Between P. semipinnata and longipinnula. 13*. P. appendiculata, Baker, in Journ. Bot. 1881, 3 66. Mada- gascar, Curtis. Like P. triplicata in texture and general habit, 14*. P. remotifolia, Baker, in Journ, Linn. Soc. XVI, 199. Mada- gascar, Miss Helen Gilpin. 16*. P. dissitifolia, Baker, in Journ. Bot. 1890, 262. Tonquin, Balansa , 1970. Near inaequalis and semipinnata. 16*. P. formosana, Baker, in Journ. Bot. 1885, 103. Formosa, Hancock , 83. Near semipinnata . 22. P. quadriaurita, Retz. P. subindivisa, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 467, tab. 56, fig. 1, Himalayas, and P. reducta, Baker, in Journ. Bot. 1880, 21 1, Sumatra, are pro- bably forms of quadriaurita with a simply pinnatifid frond. Clarke and Beddome agree in separating as a species P. grevilleana, Wall. See Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 466. 22*. P. furcans, Baker, in Journ. Bot. 18 88, 324. Borneo, Bishop Hose. discovered or described since 1874. 217 22*. P. concinna, Baker, in Malesia, III, 37. Mountains of New Guinea, Beccari. Near P. Grijfiihii , Hook. 22*. P. Walkeri, Baker, in Journ. Bot. 1888, 324. Borneo, Walker. Sent by Bishop Hose , 224, from Banggi Island, also off the coast of Borneo. 29. P. heterophylla, L. P. internata, Moore, is probably a garden variety of this species. 29*. P. maerodon, Baker, in Journ. Linn. Soc. XV, 414. Central Madagascar, Pool. 34. P. tremula, R. Br. Var .foliosa, Moore, in Gard. Chron. 1886, I, 787, is a curious monstrous garden form. 36. P. longipes, D. Don. Further material shows P. brevisora, Baker, No. 39, which has now been found in Zambesia, to be only a variety of this species, with shorter sori. Subgenus Poesia. 42*. P. Radula, Baker, in Journ. Bot. 1880, 211. Mountains of Borneo, Beccari . Near P . scaberula , A. Rich. Subgenus Campteria. 46. P. bianrita, L. P. dubia, Kuhn, in Reise Decken Bot. 71. Johanna Island, Hildebrandt , 1763, differs from the type by the want of spinules on the face and by the segments being sharply serrulate at their barren tips. 48. P. triplicata, Agardh. Further material shows P. Melleri, Baker, No. 49, to be a form of this species. 50*. P. oligodictyon, Baker, in Journ. Bot. 1889, 328. Central Madagascar. Habit of P . flabellata, Thumb, with campterioid veining. Subgenus Doryopteris. 52*. P. eordifolia, Baker, in Journ. Bot. 1891-4. North-West Madagascar, Last. Near P. sagittifolia , Raddi. Subgenus Litobrochia. 61*. P. acuminata, Baker, in Journ. Bot. 1891, 5. North-West Madagascar, Last . Near P. lanceaefolia , Agardh. 2i8 Baker . — A Summary of the new Ferns 62*. Pteris Burtoni, Baker, n. sp. Stipe naked, castaneous, 2-4 in. long, winged in the upper half. Frond deltoid, simply pinnate, j ft. long, moderately firm, glabrous ; rachis winged. Pinnae 3-7, lanceolate, entire, sessile, the largest 3-4 in. long, f-i in. broad. Veins forming 2-3 rows of areolae between the midrib and margin. Fruit not seen. Gold Coast, Burton <$f Ca?neron. Near P. splendens, Kaulf. 62. P. splendens, Kaulf. var. Miersii Baker. Pinnae only \ in. broad, more numerous than in the type; veins much less conspicuous than in the type ; areolae fewer. Rio Janeiro, Miers. 62*. P. dominicensis, Baker, in Hook. Ic. tab. 1642. Dominica, Baron Eggers, 960. 63*. P. platyodon, Baker, in Journ. Linn. Soc. XV, 415. Central Madagascar, Pool. 66. P. denticulata, Sw. I place P. Enderi, Regel, as a variety of this species. 66*. P. Pearcei, Baker, n. sp. Stipe long, naked. Frond lanceo- late-deltoid, simply pinnate, 1 \ ft. long, moderately firm : rachis stramineous. Pinnae distant, ascending, linear: lowest the largest, 8-9 in. long, with 1-4 irregular lanceolate lobes on the lower side. Veins very distinct, forming 2-3 rows of hexagonal areolae between the midrib and edge. Indusium narrow, glabrous. South America, probably South Brazil, Pearce, 271. Near P. splendens. 66*. P. Johnstoni, Baker, n. sp. Stipe naked, slender, castaneous, nearly a foot long. Frond deltoid-caudate, simply pinnate, bright green, glabrous, 6-8 in. long, chartaceous. Lower pinnae sessile, forked at the base; upper lanceolate, entire, 2J-3 in. long, f in. broad, decurrent in a narrow wing to the rachis. Veins fine, distinct, forming 2-3 rows of areolae between the midrib and edge. Fruit not seen. Sierra Leone, Dr. Halcro Johnston. Habit of P. cretica. 73*. P. similis, Kuhn, in Reise Decken Bot. 21. Niam-niam land, Schweinfurth , 3311. Much larger than P. atrovirens : final segments 2 in. long. Rachis very spinulose. 74*. P. villosa, Hort. Linden. Stipe long, naked. Frond deltoid, 2-3-pinnatifid, i-ijft. long, membranous, very hairy. Lower pinnae largest, forked at the base, lanceolate, \ ft. long,' ij 219 discovered or described since 1874. in. broad, cut down nearly to the rachis into oblong segments J in. broad. Veins anastomosing copiously. Fruit not seen. Hort. Linden. 1859, 1861, said to come from Assam. Near P. woodwardioides , Bory. 77. P. macilenta, A. Cunn. I cannot separate specifically P. pendula, Colenso, in Trans. New Zeal. Instit. 1888, 218. 77*. P. Nevillei, Baker, n. sp. Frond ample, tripinnate, membranous, glabrous : rachis weak, stramineous, naked. LowesCpinnae a foot or more long, its lowest pinnules copiously compound, with deeply pinnatifid lanceolate tertiary segments; final segments contiguous, oblong, deeply toothed, J in. broad. Veins forming 1-2 rows of areolae between the midrib and margin. Fruit not seen. Bourbon, Neville. Near P. viaci- lenta. 79*. P. platypteris, Sodiro, Recens Crypt. Vase. Prov. Quit. 28. Andes of Ecuador, Sodiro. Near P. macroptera , Link. 82. P. tripartita, Sw. This dates from 1800 and is an older name than P. marginata , Bory. Further material shows that P. milneana, Baker, is probably a mere variety of this species. 85*. P. longibraehiata, Agardh. The full material recently sent home from St. Vincent by Messrs. H. H. & G. W. Smith shows that this is probably a distinct species. Genus 33. Lomaria IVilld. 6*. L. acuminata, Baker. Also Samoa, Whitmee. An earlier name is L. norfolkiana , Heward, in Lond. Journ. Bot. I, 122. 6*. L. defiexa, Baker, in Journ. Bot. 1888, 226. West China on Mount Omei, alt. 7000 ft., Faher. Near L. norfolkiana. 8*. L. simillima, Baker, in Journ. Bot. 1884, 14 1. North-East Madagascar, Humhlot , 307. Very near the American L. Plumieri Desv. 9. L. vuleanica, Blume. I cannot separate specifically L. pauei- juga, Colenso, in Trans. New Zeal. Instit. 1888, 222. 11. L. laneeolata, Spreng. I cannot separate specifically L. aggre- gata, Colenso, in Trans. New Zeal. Instit. 1888, 223; Field, Ferns New Zeal. 103, tab. 29, fig. 7. 220 Baker . — A Summary of the new Ferns 11*. Lomaria pubescens, Baker, in Journ, Linn. Soc. XV, 415. Central Madagascar, Pool. 14*. L. leyboldtiana, Philippi, in Linnaea, XXXIII, 303. Chili, shore at Lota, Pearce . Not seen. 14*. L. Hancockii, Baker; L. apodophylla , Baker, in Journ. Bot. 1885, 104; Blechnum Hancockii , Hance, in Journ. Bot. 1883, 267. Formosa, Hancock. 18*. L. stenophylla, Baker, in Journ. Bot. 1884, 142. North-East Madagascar, Humblot , 305. 20*. L. parvifolia, Colenso, in Trans. New Zeal. Instit. 1888, 224. Exactly matches our type specimen of L. pumila , Raoul, which can scarcely be regarded as more than a variety of L. alpina. See Field, Ferns New Zeal. 106. 22. L. procera, Spreng. Under this I place Blechnum social©, Sodiro, Recens. Crypt. V asc. Prov. Quit. 3 1 . Andes of Ecuador. 22*. L. areolaris, Harringt., in Journ. Linn. Soc. XVI. Philippines, S/eere. 24. Ii. boryana, Willd. Under this I place L. stipitellata, Sodiro, Recens. Crypt. Vase. Prov. Quit. 29. Andes of Ecuador. 24*. L. microbasis, Baker, in Journ. Bot. 1880, 328. Madagascar, Hitching. 25*. L. xiphophylla, Baker, in Journ. Bot. 1884, 142. North- East Madagascar, Humblot. 30. L. membranacea, Colenso. I cannot separate specifically L. oligoneuron, Colenso, in Trans. New Zeal. Instit. 1883, 346. 31*. Ii. biformis, Baker, in Journ. Linn. Soc. XV, 415; Hook. Ic. tab. 1643. Madagascar. Fronds curiously heteromorphic. Subgenus Plagiogyria. 35** L. stenoptera, Baker; Z. concinna , Baker, in Journ. Bot. 1885, 103; Blechnum stenopterum , Hance, in Journ. Bot. 1883, 268. Formosa, Hancock. Genus 34. Blechnum Linn . 2*. B. parvulum, Philippi, Descr. Nuev. Plant. 1873, 104. Juan Fernandez. Not seen. 9*. B. rugosum, Moore, in Gard. Chron. 1884, I, 408. Garden. Not seen. 221 discovered or described since 1874. 14*. B. Whelani, Bailey, Queensl. Flora, Suppl. Ill, 92. Mountains of Queensland. Near B. serrulatum . Not seen. Genus 37. Doodia R.Br . 4*. D. polysora, Terracino, in Rend. R. Acad. Sc. Fisc., Nap., April, 1886. New Caledonia. Not seen. 5. D. caudata, R. Br. I cannot separate specifically D. squar- rosa, Colenso, in Trans. New Zeal. Inst. 1880, 382, and D. harryana, Moore, in Gard. Chron. 1884, 408. {To be continued .) Q 222 Baker. — -New Ferns discovered or described, etc. EXPLANATION OF FIGURES IN PLATE XIV. Illustrating Mr. Baker’s Summary of the New Ferns discovered or described since 1874. Matonia sarmentosa , Baker. Fig. 1. Summit of fertile segment of frond. Fig. 2. Indusium. Fig. 3. Indusium lifted up so as to show the sporangia. Fig. 4. Indusium lifted up so as to show the central stipe. (All enlarged.) voi.v,pi.xiv. fhuials of Botany M. Smith, del. University Press, Oxford. BAKER.— SUMMARY OF NEW FERNS. MAT ON IA S AR MENTOSA, Baker. NOTES. NOTE ON ME. BARBER’S PAPER ON PACHYTHECA.— Few fossils have been the subject of more varied explanation than Pachytheca . This has arisen from the fact that any positive indica- tions as to its structure have been so meagre. The careful investiga- tions of Mr. Barber tell us pretty well all that we are ever likely to know, and at any rate supply us with definite grounds for rejecting the greater part of the hypotheses which have been put forward with regard to it. More than ten years ago I carefully investigated the specimens of Pachytheca belonging to Sir Joseph Hooker at his request. I arrived at these conclusions : — (i) That the cortical cells branched, (ii) that the cortical cells and the medullary filaments were continuous, and (iii) that the structure of the whole organism was comparable with that of known Algal types. On the occasion of Sir W. Dawson’s paper on Prototaxites being read at the Geological Society, on Nov. 1 6, 1 88 1, my friend, Prof. Judd, asked me to make some statement about Pachytheca. It will be convenient to reprint from the Pro- ceedings what took place. ‘ Prof. Judd stated that he exhibited, on behalf of Mr. Thiselton- Dyer, two sections of Pachytheca. Mr. Thiselton-Dyer regretted that he was unable to be present at the Meeting, but had sent Prof. Judd a letter, from which he read the following extract : — “Kew, Nov. 15, 1881. “Some time ago Sir Joseph Hooker received from Mr. Grindrod a number of specimens of Pachytheca in situ on pieces of rock. As these examples of the fossils were apparently well preserved, two or three were detached and intrusted to Mr. Norman, who made the sections which are now in your hands. Sir Joseph Hooker did not see his way to any definite conclusion as regards the structure which they exhibited. He, however, allowed me to examine them, and they have since remained in my possession. The conclusion which I arrived at was that [Annals of Botany, Vol. V. No. XVIII. April, 1891.] Q % 22 4 Notes . their structure agreed in general plan with that of C odium, as shown in Kiitzing, ‘ Phycologia Generalis/ PI. 42, Fig. 1. “ As a possible algal nature has been suggested for P achy theca by Mr. Etheridge, I think it may not be considered presumptuous on my part to now state that I have been of opinion ever since I studied the sections, that Prototaxites and Pachytheca are both referable to the same morphological type of structure. The radiating cells in the latter terminate internally in loosely inter- lacing slender filaments, with which the central cavity has been apparently filled. Pachytheca does not resemble any type of sporangium with which I am acquainted ; the structure, as dis- played in the specimens, has a certain resemblance to that of the sporocarp of Pilularia ; but I cannot reconcile what I have seen of it with the supposition that it was a reproductive structure belonging to any type of vascular cryptogam. ‘ According to the view which I take of Pachytheca , it was an algal organism closely resembling in essential structure a diminu- tive Codium , but with the peripheral cells branched instead of simple. I do not see any evidence to lead me to suppose that it was related to Prototaxites as a sporangial organ. The existence of Prototaxites on modern biological views necessarily implies the existence, at some time or other, of allied forms, and I do not see why Pachytheca should not have been a contemporaneous one.” * I should not recall the past history of an observation, which to me is not of very great importance, were it not that in his paper Sir Joseph Hooker pointed out that I stood alone in asserting that the cells of the cortical and peripheral tissue were continuous. ‘ This organic connection/ he says, ‘ between the tissue of the cavity and walls is, if confirmed, a fact of very great importance. It has escaped my own notice and that of several excellent observers, who had devoted much time to the study of my specimens.1 ' I think it is not without interest to point out that it has been confirmed. Mr. Barber has obtained independent evidence of the fact in one of the sections, which I myself have not seen, described in his present paper. He remarks, however, 1 this is, I believe, the first specimen, if not the only one, in which cortical and medullary filaments have been seen to join one another/ I can only say that I determined the fact of their 1 Annals of Botany, III, pp. 138, 139. Notes . 225 continuity in one of Sir Joseph Hooker’s sections, or I should not have placed it on record. But I am not prepared to say that I saw it with anything like the precision which is exhibited in the section examined by Mr. Barber. I make these remarks in justice to myself. But I do not wish to detract in any way from the excellence of Mr. Barber s papers. He has placed our knowledge of Pachytheca on solid ground which it had never before attained, and has added to that knowledge a number of new facts of great importance, which he has interpreted in a very skilful and convincing manner. I may take the opportunity of saying that there is, I think, some little misapprehension on Mr. Barber’s part with regard to the curious round calcareous pebbles which occur in such profusion at the bottom of Lough Belvedere, near Mullingar \ I never found time to give these pebbles a more than superficial examination. They certainly deserve, however, a more minute study than I think they have yet received. An accumulation of them might easily form a rock, and the interpretation of its structure would not be easy. When the pebbles, which are of all sizes up to that of a filbert, are digested in a weak acid, the lime is removed and an algal mass remains of the same size and form. The bulk of this consists of a Rivularia : but if I remember rightly, my friend Mr. Archer, F.R.S., told me that he had detected other algae casually interwoven in the mass. But I have no recollection of observing anything confirming Mr. Barber’s statement that there is any symbiosis of Rivularia and Cladophora, or penetration of the former by the latter. The analogy which suggested itself to my mind between these curious pebbles and Pachytheca rested on a different point. The Mullingar Rivularia evidently has the power of incrusting itself with calcium carbonate, and I cannot help thinking that Pachytheca when a living organism must have had a similar propensity. If so, the incrusting material would undergo considerable change in the process of fossilization : but this would account for the manner in which its filamentous structure, which otherwise one would have expected to be very perishable, is so considerably preserved. W. T. THISELTON-DYER, Kew. 1 Annals of Botany, III, p. 144. 226 Notes. ON THE ANTHERIDIA OP LOME NT ARIA. —At Woods Holl, Mass., this summer (July 26, 1890), while examining material of Lomentaria uncinata , Menegh., collected in Vineyard Sound, tips Fig. 2. Several camera lucida outline sketches of antheridia-bearing tips. Fig. 3. Central longitudinal section through an antheridia-bearing tip. bearing antheridia were discovered. From the literature at my com- mand and from inquiry, it would appear that the antheridia of Lomentaria have seldom been seen, consequently a brief note on their position and structure may not be without interest. They are found usually at the ends of the branches of the frond, Notes. 227 forming little spherical heads much resembling in position the antheridia of Griffithsia Bornetiana , Farlow, in which, however, they are spread out over the apex forming a hood-like covering, and do not, as in Lomentaria , form an enlarged head (Fig. 2). While the position is usually directly apical, several tips were found where, by the partial branching or merely deflexed onward growth, the position had become somewhat lateral. Several of the antheridial plants were found, one of which bore also numerous tetraspores. In general appearance and manner of growth I cannot distinguish the male plant from the common tetra- sporic and sterile plants. Serial sections through an antheridial tip show the head to be a tuft of short (30-35 fx long), radiating, clavate, 2-3 or 4-celled filaments originating from the apical cells of the tip and bearing at their extremity the antheridial mother-cells (Fig. 3). Dr. W. A. Setchell, who examined my material at the time, informs me that he shortly after discovered undoubted antheridia of Champia parvula (Ag.) Harv., a closely related plant. It was merely a frag- mentary specimen and unfortunately was destroyed. Their position and appearance, he reports, accord entirely with those of Lomentaria uncinata, Menegh. H. J. WEBBER, St. Louis, Mo. ECTOCARPUS FENESTR ATU S. — Messrs. Holmes and Batters include this species in their ‘ Revised List of British Marine Algae1.’ As far as I know, the single type-specimen exists in the Kew Herbarium, to which it came from that of the Rev. M. J. Berkeley. The herbarium of Mrs. Griffiths does not appear to contain any example. With some reluctance, and as a wholly exceptional case, I entrusted this unique specimen to Dr. Bornet for examination. It will be inter- esting to quote the following extract from a letter which I have received from him, dated February 24 : — “ Je vous retourne le pr^cieux dchantillon que vous m’avez confix. Sa fragility est telle qu’il est fort difficile d’en detacher des filaments ; j’ai pourtant r£ussi, sans lui causer aucun dommage perceptible, a en prendre une id£e suffisante pour que sa determination soit a peu prbs 1 Annals of Botany, V, p. 79. 228 Notes . assurde. Afin qu’on n’a plus a y toucher, je joins a l’exemplaire un croquis exact des sporanges, dont la forme est fort diffdrente de celle que Harvey a repr^senffie. Autant qu’il est permis d’en juger, d’aprbs un £chantillon incomplet et qu’on ne veut pas risquer de detruire, je rapporte X Ectocarpus fenestratus a l’espece qu’on nomme aujourd’hui E. Lebelii ; selon toute apparence, l’^chantillon est un exemplaire a antheridies, beaucoup plus d^veloppe que d’habitude. Quelques espbces voisines, telles que les E pusillus et insignis , pr^sentent par- fois un developpement semblable. Done, grace a vous, voici une question dclaircie/ W. T. THISELTON-DYER, Kew. TYPE-SPECIMENS OE MRS. GRIFFITHS.— In the introduc- tion to ‘ A Revised List of the British Marine Algae/ by Messrs. Holmes and Batters, the authors remark 1 : ‘ It may be useful to state that in the course of our investigations we have found that the type-specimens of the following authors are deposited in the herein-stated herbaria ’ : — Then follows a list, in which I find 1 Mrs. Griffiths, Linnean Society, London/ This seems to me to need a word of comment. In the ‘ Report on the Progress and Condition of the Royal Gardens at Kew’ for the year 1862 I find, amongst the additions to the Herbarium ‘ The unrivalled collection of British Seaweeds , formed during a long life devoted to that order of Plants, by Mrs. Griffiths, of Torquay. Presented by Miss Burdett-Coutts/ I believe that this herbarium was very extensive, and that there were vast series of specimens representing each species. Mrs. J. E. Gray was about this time in the habit of residing at Kew during part of every summer. Sir William Hooker entrusted to her the task of selecting a series of specimens which would represent Mrs. Griffiths' types ; these at the present moment are undoubtedly preserved in the Kew Herbarium. And the fact is well known to critical algologists, for Dr. Bornet, writing to me recently, mentions incidentally : — ‘ L’herbier de Mme Griffiths et celui de Berkeley sont conserves au Musee de Kew/ As I have said, the herbarium was extensive, and there were vast quantities of duplicates, such as a private collector might preserve for some purpose or other, but which would be of little use in a public 1 Annals of Botany, V, p. 66, Notes. 229 collection. A large proportion of these were distributed, and it is only recently that the last remains have been disposed of. A con- siderable proportion were placed at the disposal of Mrs. J. E. Gray, in recompense for her pains and trouble in arranging the type-collection. These (I believe with duplicates from her own herbarium) she made up into sets and, bound in handsome volumes, distributed to various public institutions. One such set may be in the possession of the Linnean Society. But the type-collection is certainly not there, for the simple reason that it is where it has always been since Mrs. Griffiths’ death — at Kew. The same authors state that Mrs. J. E. Gray’s own type-specimens are at ‘ Cambridge University.’ I strongly suspect that what Cam- bridge possesses is one of the collections referred to above. I can hardly doubt that Mrs. J. E. Gray enriched the Kew Herbarium of Algae, which was practically for some years under her charge, with any specimens of her own which would be of value to it. W. T. THISELTON-DYER, Kew. R Contributions to the Life-History of Isoetes. BY DOUGLAS HOUGHTON CAMPBELL, Professor of Botany in the Indiana State. University .. With Plates XV, XVI, XVII. SINCE Hofmeister first called attention to the homologies existing between the heterosporous pteridophytes and the spermaphytes, the genus Isoetes has always been an object of special interest to botanists, and the subject of numerous investigations, as it is, in some respects, undoubtedly the nearest to the spermaphytes among all known living pterido- phytes. For this reason a thorough study of the life-history of some species, as compared with other pteridophytes, has long been a desideratum, both as a means of determining to which class of the pteridophytes Isoetes is most nearly allied, as well as, if possible, to throw some light upon the origin of the spermaphytes. The mature sporophyte1 has been thoroughly studied, and the development of the sporangia and spores 2 has been care- fully investigated. Since Hofmeister’s 3 work, however, but little has been done upon the female prothallium ; but Mil- lardet4, and later Belajeff5, have described in detail the germination of the microspores and the development of the 1 Hofmeister, De Bary, Brachmann, See. 2 See especially Goebel, Beitrage zur vergleichenden Entwickelungsgeschichte der Sporangien, Bot. Zeit. 1880-1881. 3 Hofmeister, Higher Cryptogamia, pp. 336 ff. 4 Le prothallium male des crypt, vase. 5 Belajeff, Bot. Zeit. 1885, pp. 793-809. [Annals of Botany, Vol. V. No. XIX. August 1891] S 232 Campbell \ — Contributions to the male prothallium, and Kienitz-Gerloff1 has corrected some of Hofmeister’s errors in regard to the embryo. There are serious difficulties in the study of the germinating macrospore and young embryo ; indeed, so great are these that without the aid of the modern histological methods, they are quite insurmountable. Free-hand sections of the fresh macrospore and young embryo are impossible, and even in the later stages very difficult. Having successfully imbedded in paraffine and sectioned the macrospores of Pilularia 2 and Marsilia 3, the study of the development of the female pro- thallium of Isoetes was taken up, in the hope that by the same methods the early stages might be successfully made out. Although it proved a difficult task, it was at last possible to trace out the whole development of both the prothallium and the embryo. A brief summary of the most important points in the development of the former has already appeared 4. Owing to the thick and impervious exospore, great care is necessary in imbedding to prevent shrinkage, and even with every precaution, many preparations proved perfectly worth- less. This was especially true with young prothallia after the formation of the cell-walls, but before the exospore was ruptured. On the whole, material fixed with one per cent, aqueous solution of chromic acid proved most satisfactory. After washing thoroughly and dehydrating, the specimens were gradually brought into turpentine, and after remaining several hours in a saturated solution of paraffine in turpentine, were placed in melted paraffine for from six to eight hours, and then imbedded for sectioning. At first chloroform was used in- stead of turpentine, but it almost invariably caused shrinkage, and so was finally abandoned. When chloroform is used, a much shorter time (two to three hours) is usually sufficient for a thorough saturation by the melted paraffine. 1 Kienitz-Gerloff, Entwicklung des Embryos v. Isoetes lacustris\ Bot. Zeit. 1881. 2 Campbell, on Pilularia globulifera ; Annals of Botany, vol. II., no. VII. 3 Campbell, on Marsilia Aegyptiaca ; Ber. der Deutschen Bot. Gesellschaft, 1888, VIII. 4 Berichte der Deutschen Bot. Gesellschaft, 1890, No. III. Life-History of Isoetes. 233 After the specimens were imbedded they were sectioned with a Minot-microtome, stained on the slide, and mounted in Canada-balsam. While safranine and gentian-violet, in water, give a good nuclear stain, the young cell-walls colour but little, and often do not show as clearly as could be wished, Bismarck-brown, however, particularly when dissolved in 70 per cent, alcohol, stains the young cell-walls especially well, and is by far the best stain for this purpose that I have yet found. Extremely beautiful preparations of the older pro- thallia and embryos were made by staining in toto with alum-cochineal or Kleinenberg’s haematoxylin, for a nuclear stain, and then staining on the slide with the Bismarck-brown. In the younger stages, however, nearly all attempts at staining in toto were ineffectual. Bismarck-brown is especially satis- factory also, in that it does not overstain, and is not readily extracted by alcohol, so that there is not the danger of too much decoloration in dehydrating the specimens that is met with when using other aniline colours. I am especially indebted to Mr. F. V. Coville of Washington, through whose kindness a very abundant supply of fruiting specimens of Isoetes echinospora , var. Braunii , Durieu, was sent me. The plants were collected in the vicinity of Washington in September, 1889, and at this time the spores were ripe, or nearly so. The plants were kept in an aquarium with about an inch of sand at the bottom, and remained in good condition through the winter, resuming growth vigorously the following spring. The spores are ordinarily set free by the decay of the sporangium-wall, and this does not occur, probably, until late in the autumn or winter, when the plants are growing under normal conditions ; so that probably the spores do not ger- minate naturally until spring. If, however, they are set free artificially, they will begin to germinate very soon, but the process is slower than when set free spontaneously. The first sowings were made by me Sept. 27, and from that time on, at intervals, through the autumn and winter. There was much difference shown in the promptness of ger- mination, even in the same lot ; and as the absolute opacity 234 Campbell . — Contributions to the of the exospore renders it quite impossible to judge of the stage of development in the living spore, we can only judge of the time necessary for the different stages of growth, by a comparison of sections, and this, of course, can give only an approximate idea. Of the first lot, sown Sept. 27, the youngest spore, in which the first division of the primary nucleus was observed, was nineteen days old ; but in one case, at least, a spore of the same age had advanced beyond this point, and to judge by comparison with others, was probably two or three days in advance of those in which the first divi- sion of the primary nucleus was seen. The youngest full- grown prothallia observed were from a week to ten days older, and the first young plants broke through the prothallium almost exactly one month from the time the spores were placed in water. The germination of the microspores is more rapid, but the exact time was not noted. Owing to the transparency of the exospore the time required can be de- termined with much greater exactness than is the case with the macrospores. Spores sown later germinate more rapidly. Sowings were made Dec. 13, and just three weeks later (Jan. 2) the first young plants were noted, the leaf being already green and about one centimetre in length. Micro- spores sown about the same time produced the first ripe spermatozoids in two weeks. The Male Prothallium. The microspores are borne in the sporangia at the bases of the inner leaves, and are of the bilateral type of spores, i. e. each is in form the quadrant of a sphere. The exospore is nearly colourless in the species under consideration, smooth, and sufficiently transparent to allow a plain view of the in- terior of the spore. Owing to this the development of the antheridium is easily followed in the living spores. As the germination of the microspores of I. lacustris has already been exhaustively treated by Millardet1 and Belajeff2, and I. echinospora does not differ in any respect from that species, Loc. cit. 2 Loc. cit. 235 Life-History of Isoetes. no detailed account will be given here. The vegetative part of the prothallium is reduced to a single small cell cut off from one end of the spore ; the remainder of the spore forms the antheridium, as in Marsilia 1. In the antheridium two walls are formed so inclined to each other as to include two upper cells and one lower. This latter next divides into two by a vertical wall, and subsequently by a periclinal wall is further divided into two peripheral and two central cells. Each of the latter divides once more, and each of the four central cells thus formed is the mother-cell of a spermatozoid. The full-grown antheridium thus consists of four peripheral and four central cells, and is therefore the most reduced among the pteridophytes. In many instances the microspores were imbedded with the macrospores, and as the nuclei could then be stained, the number of the peripheral cells, as well as the origin of the spermatozoids, was readily made out. The latter are too small in this species to be a good subject for the study of their development; but there is no doubt that, as in other cases, the body of the spermatozoid is derived mainly from the nucleus of the sperm-cell. At all stages it colours very intensely with gentian-violet, while the surrounding proto- plasm remains entirely colourless. Like the spermatozoids of the Filicineae, the body of the spermatozoid is spirally coiled, and multi-ciliate. Belajeff2, in a recent paper, opposes the generally accepted view that the body of the spermatozoid is of nuclear origin, and claims that only a small portion of it is derived from the nucleus. His views, however, are not supported by the recent work of Guignard on this subject, nor have I been able to find any confirmation of his state- ments from a careful study of a number of forms. 1 Campbell, loc. cit., p. 341. 2 Ueber Bau und Entwickl. d. Spermatozoiden bei den Gefasscryptogamen ; Ber, der Deutschen Bot. Gesellschaft, 1889, p. 122. 236 Campbell, — Contributio?is to The Macrospore and Female Prothallium. The macrospores are formed in the sporangia of the outer leaves, and are very much larger than the microspores, from which they differ in form, being of the tetrahedral type. They are nearly globular in form, and, like most tetrahedral spores, the three ridges where the spore is in contact with the others of the tetrad, are very conspicuous, and may be seen with a hand-lens. If the fresh spore is crushed in water, its contents appear milky, and microscopic examination reveals oil-drops and some starch-granules mingled with roundish bodies of albuminous nature. The latter absorb water more or less, and look almost like free cells. While, as we have already stated, it is quite impossible to section the fresh spores, by hardening with alcohol or chromic acid, it is not difficult to imbed them, and then sections may be easily made; and when stained with some aniline colour (gentian-violet or safranine), the structure is readily made out. The wall of the spore is composed of several layers of which the outer one (Epispore) is thick and glassy in texture, and in our species provided with short recurved spinules (Fig. 40, sp). The interior is filled with coarsely granular proto- plasm that often appears spongy, owing probably to the dissolving out of the oil in the process of imbedding (Fig. 1). Scattered through the spore are round starch-grains (Fig. 1, s), having a central hilum. Besides the starch-grains are nu- merous somewhat irregular bodies (Fig. 1, Al) that stain strongly with gentian-violet or safranine, and seem to be albuminous reserve-materials. The nucleus is large and readily seen. It lies in the basal part of the spore — that is the part opposite the point of contact with the other spores of the tetrad. The nucleus is broadly elliptical in form, and a small space about it is usually nearly free from the larger starch-grains and albuminous granules. Not infrequently, between the nucleus and the wall of the spore, a close layer of small starch-granules was observed that was very con- spicuous (Fig. 1, /). The nucleus (Figs. 2, 3) has a delicate, 237 Life-History of Isoetes. but evident membrane, and usually one large nucleolus. This stains somewhat with gentian-violet and safranine, but not very deeply: and while a faint reticulate structure may be seen, it does not stain. The nucleus of the resting spore, it will thus be seen, is very poor in chromatin. In my preliminary paper1, the statement was made that the nucleolus, even in the ungerminated spore, stains strongly, but a further examination of the preparations showed that this was only true in spores that had been free for some time, and indicated, presumably, the first stage in their germina- tions. A number of spores taken directly from the sporangium and sectioned, showed but very slight coloration of the nucleolus. After the spores have lain a few days in water, the nucleus increases somewhat in size, and then the nucleolus colours very intensely. At the same time several smaller bodies, likewise strongly coloured, and resembling the nucleolus except in size, are usually to be seen (Figs. 4, 5)« In these nuclei, too, there is a central area that colours faintly, and later (Figs. 4 and 5), in this area the nuclear filaments can be seen, and small chromatin-corpuscles become visible. Although a large number of sections were made, the further changes in the nucleus, preliminary to its division, were not seen, and only twice was the primary nucleus of the spore found in actual division, in both cases nineteen days after the spores were sown. In the younger of the two the chromatin- masses were distinct and in the form of nearly round granules. The outlines of the daughter-nuclei could be faintly traced, but no membrane had yet formed. Very numerous connect- ing threads were seen between the young nuclei, and a very evident cell-plate occupied the equator of the nuclear figure. The older stage (Fig. 6) had the membrane of the daughter- nuclei better defined, and the chromatin-masses had apparently partially coalesced. No cell-wall is formed, and the result of the first division is two free nuclei. The first division takes place while the nucleus is in its original position, but whether 1 Loc. cit., p. 99. 2 38 Campbell \ — Contributions to the • the secondary nuclei also divide before moving to the apex of the spore I cannot say, as the next youngest stage observed had four free nuclei, and these lay in the apical part of the spore, with no indication whether they had assumed this position before or after the division of the secondary nuclei. These nuclei were much smaller than the primary one which, however, they resemble in structure, except that they have relatively more chromatin than the nucleus of the resting spore. They lie close to the periphery of the spore, and the surrounding cytoplasm is much more finely granular than that of the interior of the spore, and colours much less strongly with gentian-violet. The nuclei now divide rapidly, becoming at the same time much smaller, until a considerable number (usually from thirty to fifty) of free nuclei are formed ; but as yet there is no trace of division-walls between them. By far the larger number of the nuclei lie in the upper part of the spore, but sometimes an occasional one may be detected in the basal part or centre ; but these portions are usually destitute of nuclei at the time when cell-formation begins. For the demonstration of the nuclei at this time, the sections should be overstained with gentian-violet, and the superfluous colour removed with alco- hol. In this way the nuclei remain strongly coloured after the cytoplasm is entirely decoloured. The first trace of cell-formation is at the apex of the spore. At this time the cytoplasm colours more deeply than before, and sometimes very delicate threads may be detected, radi- ating in all directions from the nuclei and connecting the adjacent ones (Fig. 8). Shortly after, the first traces of the division-walls appear simultaneously between the nuclei, in the form of cell-plates composed of minute granules (micro- somes), presumably of cellulose. The separate microsomes quickly coalesce and form the continuous membrane of the young cell- wall. In this way the upper part of the spore be- comes transformed into a solid tissue (Figs. 9, 10). The cell-formation proceeds quickly toward the base of the spore, following the spore-wall, so that for a time the central 239 Life-History of Isoetes . part remains undivided. The whole process recalls most vividly the endosperm-formation in most angiosperms. Owing to the dense contents, and the extremely thin cell-walls, it is not easy to determine exactly when the whole cavity of the spore becomes filled with the cellular tissue. On account of the preponderance of the free nuclei in the upper part of the spore, and their consequent proximity to each other, the cells of the prothallium in this region are smaller than those in the lower and central part of the prothallium (see Figs. 10-12). The divisions in these upper cells, too, are more frequent, and sometimes the transition from the upper small-celled tissue to the lower large-celled is quite abrupt, and all the more noticeable as the upper cells are comparatively free from the coarse granular contents of the lower cells. After the first cell-walls are complete, the subsequent nuclear division is accompanied regularly by the formation of division-walls be- tween the daughter-nuclei. The process here described it will be seen is very similar to that found in the usual endosperm-formation of the sperma- phytes, and differs very much from Hofmeister’s account 1, according to which free cells are first formed that afterwards coalesce to form the prothallium. Only in a very few instances, and these mostly later stages, was any appearance noted that had the appearance of a splitting of the protoplasm, as Farmer2 describes, and this was readily shown to be due to shrinkage caused by the action of reagents, and with a little care it was evident that in all such cases cell-walls were present, and that the apparent cracks simply marked their position (Fig. 40). The first archegonium is very early evident, generally before the cell-division is completed in the lower part of the spore. The mother-cell (Fig. 10, a) occupies the apex, and is early re- cognisable on account of its larger size and denser contents. It is simply one of the first-formed cells that ceases to divide after it is complete ; and as the neighbouring cells divide rapidly, the contrast in size between it and those adjoining becomes very marked. Whether seen from above or in profile, it usually 1 Loc. cit.,.p. 339. 2 Proceedings of the Royal Society, vol. 45, p. 307, 18S9. 240 Campbell.— Contributions to the appears triangular, or nearly so, in outline, the walls bounding it meeting so as to enclose a nearly regular tetrahedron. The nucleus is also evidently larger than those of the surrounding cells. A notable point connected with the archegonium, and also true of the later ones, is the large size of the mother- cell as compared with that of the archegonium of most pteri- dophytes. Of the other pteridophytes, the Marattiaceae 1 approach most nearly to Isoetes , as they do in the structure of the mature archegonium. The development of the first as well as the later archegonia is the same, and follows closely that of the Filicineae, showing especially close resemblances to the Marattiaceae. The mother-cell (Fig. 13, ci) first divides by a transverse wall into two cells, of which the outer smaller one gives rise to the neck of the archegonium, the inner larger one to the central cell and the neck-canal-cell. The first division in the inner cell is parallel to the first wall in the archegonium mother-cell, which thus becomes divided into three cells placed one above another (Fig. 14). The contents of these cells are quite similar and the nuclei large and distinct. The next divisions occur in the neck-cell, which is divided by vertical walls, at right-angles to each other, into four nearly equal cells. These mark the four rows of cells composing the neck. Each of the neck cells next undergoes division by a transverse wall into two, and each of the latter in the same way into two more, so that the mature archegonium has a neck composed of four rows, each com- posed of four cells (Figs. 1 6, 17). Almost simultaneously with the first transverse divisions of the neck-cells, the central cell has cut off from its upper part the ventral canal-cell (Figs. 15, 16, b), which is larger than is common, being the whole breadth of the central cell. In the meantime the neck-canal-cell ( h ) has pushed up between the neck-cells, but while very broad, is relatively much shorter than usual. The neck-canal-cell has at first a single nucleus, but this, 1 Jonkman, La generation sexuee des Marattiacees, Figs. 99-105. Life-History of Isoetes . 241 at least in some instances, divides as in most ferns, but there is no division-wall formed (Fig. 17). As the archegonium approaches maturity, the neck-cells elongate somewhat, and the two upper tiers project above the surface of the prothallium (Fig. 16). Shortly before opening, the walls of the canal-cells, as usual, become disorganised, and with their contents form a mucilaginous mass which is expelled when the archegonium opens. At the same time the contents of the mother-cell of the egg-cell contract and become nearly globular. The act of opening of the archegonium was not observed, but stages shortly before and after were met with. The egg-cell (Fig. 18, 0 ) is a large round or oval naked cell with a large and clearly marked nucleus, having a very large nucleolus that stains with great intensity; but besides the nucleolus there seems to be but little chromatin. The upper part (about one-third) of the egg is composed of hyaline protoplasm, exhibiting a faintly reticulate structure, and forms the c receptive spot.’ The lower part, surrounding the nucleus, is filled with granules, and stains strongly with gentian-violet. Owing to the small size of the spermatozoids and the great difficulty of getting satisfactory sections of ripe archegonia, the actual process of fertilization was not seen, and I am not pre- pared to state positively what the first results of the process are. In one or two cases noted, where the egg had apparently been recently fertilized, the receptive spot had disappeared and the protoplasm had become uniformly granular throughout. The ripe archegonium closely resembles that of the Marat- tiaceae. It is sunk in the prothallium except the two upper tiers of neck-cells, and both in this respect, as well as the very broad canal-cells, resembles closely Jonk man’s figures1 of Angiopteris and Marattia . The egg-cell, however, is relatively much larger. Owing to the small increase in size, during its growth, there is very little displacement of the cells of the archegonium and its limits are very definite. In Isoetes lacustris , according to Hofmeister 2, only one archegonium is formed at first, and if this is fertilized no 2 Loc. cit., p. 340. 1 Loc. cit. 242 Campbell ’ — Contributions to the others are produced ; but in I. echinospora (and it is not un* likely that further investigation will show that it is true for /. lacustris as well), even before the first archegonium is com- plete, two others begin to develop, and reach maturity shortly after the first, whether it is fertilized or not. In case these all fail to be fecundated a small number (probably never more than five or six) may be formed subsequently; but so far as my observations go, the production of archegonia on the old, unfecundated prothallium, is very limited, as is the growth of the prothallium itself. In no instance was the formation of chlorophyll noticed, and only in the rarest instances were root-hairs developed from the superficial cells, so that the prothallium is entirely dependent upon the food-materials contained in the spore for its growth, and when these are exhausted must necessarily perish. As the prothallium be- comes older, the cell-walls become firmer, and more evident on account of the absorption of the food-materials in the cells, which for this reason become more transparent. In regard to the development of the female prothallium, Isoetes stands alone among pteridophytes so far as we know at present, although it is possible that an investigation of the earlier stages of the prothallium of Selaginella may show analogies ; but the fact that the true prothallium of the latter is separated by a membrane from the lower part of the spore would point rather to a formation by true cell-division, as in Marsilia 1 and Pilularia 2. The oophyte of all other hetero- sporous pteridophytes is capable to some extent of inde- pendent growth, and this is especially true of the Filicineae, in which it develops chlorophyll, and may increase very considerably in size, provided the archegonia are not fertilized. Indeed the development of the oophyte of Isoetes resembles much more nearly that of the gymnosperms, or the endosperm of the angiosperms, than it does the prothallium of any pteri- dophyte, and in this respect must be regarded as the nearest approach to the former among the pteridophytes. 1 Loc. cit. 2 Loc. cit. Life-History of Isoetes . 243 The Embryo. The youngest embryos observed had the first division-wall already complete (Fig. 19). This is transverse, but more or less inclined to the axis of the archegonium. The nuclei of the two cells are large, and contain several chromatin-masses. The second divisions in the two halves of the embryo do not always occur simultaneously, the lower half dividing some- times before the upper, and at times the first walls in the two parts are at right-angles to each other instead of in the same plane, as is usual. Of the quadrants resulting from these divisions, the two lower form the foot, which is here large, and of the upper one forms the first leaf, and the other the primary root. The apex of the stem, which always is very inconspicuous, arises between the bases of the leaf and root, and probably belongs to the same quadrant as the latter ; but as it does not project at all, and is not certainly recognisable until after the boundary between the quadrants is no longer evident, this cannot be asserted positively. Sometimes (see Fig. 31) the quadrants divide by vertical walls into nearly equal octants, but in several young embryos observed (see Fig. 25) no regular octant-wall was formed, at least in the upper quadrants, but whether such irregularities were normal it is difficult to say, and it is certain that some- times, at any rate, and probably in most cases, the embryo is divided into regular octants as in the ferns. The next divisions also follow much the same plan as in the fern-embryo, and for a short time the young members may be said to grow from an apical cell, inasmuch as the tetrahedral octants at first have segments cut off parallel with the basal, quadrant, and octant walls, leaving an outer cell (Fig. 24, a) that still retains the original form ; but very soon periclinal walls are formed in this cell in each quadrant, and it is no longer recognisable as an apical cell. Unfortunately, on ac- count of the great difficulty of making successful sections of the very young embryos, it was not possible to get a sufficient 244 Campbell. — Contributions to the number of satisfactory preparations to determine positively, or for how long this regularity of growth persists. Up to this time the embryo has increased but little in size, and has the form of a globular or oval cellular mass in which the organs are not differentiated. In proportion as the basal- wall diverges more or less from, the horizontal, so does the axis of the first leaf which is parallel with it. Occasionally the basal-wall is so nearly vertical that the young leaf grows upright, penetrating the neck of the archegonium at right- angles to its usual course. The embryo now rapidly elongates in the direction of the basal-wall, and very soon there may be distinguished in the upper portion a division into leaf and root (Figs. 27, 28). The original quadrant-wall remains distinct for some time, and is especially evident in transverse sections (Fig. 29, II II). At the base of the leaf, at this stage, a single cell (Fig. 27, x), larger than its neighbours, may sometimes be seen. This is the mother-cell of the ligule, which is so con- spicuous a feature of all the leaves. If we compare the young embryo at this stage with that of other pteridophytes, we find that it does not agree exactly with any, but on the whole resembles that of the various Filicineae that have been examined. The greatest difference, apart from the absence of a single apical-cell in the young members, is the different position of the stem. This in all the true ferns examined arises from one of the lower quadrants, which here takes part in the formation of the foot, while the stem-apex in Isoetes , as already stated, arises between the leaf and root that is from one of the upper quadrants. Longitudinal sections of the embryo at a time when root and leaf become first clearly recognisable, show that the foot is not clearly limited (Fig. 28,/), as the basal-wall of the embryo early becomes indistinguishable on account of the displacement due to the rapid cell-multiplication in the axis of the embryo ; nor is it as conspicuous as in the later stages (Figs. 39-41), projecting but little, and not having its cells noticeably larger than those of the root and leaf. These now (Figs. 28, 30) have the form of a blunt cone, the latter some- 245 Life- History of Isoetes . what longer and more pointed, but in neither is there any longer any trace of a single apical-cell. At the base of the leaf, which is now separated from the root by an evident de- pression, the ligule is usually (Fig. 28, x) visible, as a short row of cells lying close to the base of the leaf. A vertical transverse section of an embryo of about the same age (Fig. 31) shows that the ligule is already divided by walls in two planes, these walls being arranged with great regularity. Hofmeister 1 compares the divisions to those in the young gemmae of Marchantia , and the resemblance is quite striking. The ligule later divides further by both longitudinal and trans- verse walls until it may reach a breadth of from ten to twelve cells, with a length of about the same (Figs. 46, 49). Very soon after the ligule becomes visible, the base of the root, which lies close to it, begins to project in the form of a semicircular ridge (Fig. 30, v) that grows rapidly and forms a sheath enclosing the ligule, together with the base of the leaf. The sheath increases by the division of the marginal cells, from whose bases cells are cut off which divide further and thus add to the sheath, and increase the depth of the space inclosed by it. A number of cells at the bottom of the furrow, between the sheath and the base of the leaf, constitute the apex of the future stem of the plant. As they differ in no wise from the neighbouring cells, it is quite impossible to say how many of them belong properly to the stem-apex. The Leaf . — The first leaf, as we have seen, arises from one of the two upper quadrants, and may for a very short time be said to have a single apical-cell ; but very early all trace of a definite apical growth is lost, and the lengthening is soon due to rapid division of the cells at the base. At first nearly cylindrical, it soon becomes slightly flattened and the primary tissue-systems are plainly evident. The first periclinal walls in the embryo probably separate the dermatogen from the inner tissues, which do not show a further division into ple- rome and periblem until a much later stage. At any rate, in 1 Loc. cit., p, 346. 246 Campbell . — Contributions to the all but the very youngest embryos, the dermatogen in the leaf is very plain. About the time that the first divisions in the ligule are formed, a few cells near the centre of the embryo cease to divide by transverse walls, but elongate in the direction of the longer axis of the embryo, and dividing longitudinally, form a bundle of narrow cells, the first trace of the fibro-vascular system of the young plant. This first group of cells lies so near the centre of the embryo that it is not possible to assign it certainly to either root or leaf; indeed in some cases it seems to belong to one quadrant, and again to the other. From it, in both directions, the development of the single axial bundle of both leaf and root proceeds, and by it they are both directly connected. A cross-section of these cells shows them to be of nearly equal diameter (Fig. 31). The section of the plerome- cylinder is somewhat elliptical, corre- sponding to the flattening of the leaf, and the appearance of the longitudinal sections differs as the section is made parallel to the flattened surface of the leaf, or at right-angles to it. In the former case, the diameter of the plerome is uniform, and it ends abruptly (Fig. 43). In the latter, it is narrower and tapers gradually to a point (Fig. 39). In both views its limits are clearly defined, as are those of dermatogen and periblem. The plerome-cylinder never extends entirely to the apex of the leaf, but is separated from it by several rows of cells. In the periblem, the divisions are mainly transverse, and the cells are therefore arranged in quite regular rows ; this is especially marked in horizontal sections (Fig. 43). Now begins a rapid growth in length, due partly to an increase in length of the cells at the tip of the leaf, and partly to the rapid transverse divisions and growth of the basal cells. The cells of the prothallium grow for a time, following the growth of the embryo, but soon the cells are ruptured and the young leaf protrudes, and having now developed abundant chlorophyll, appears to the naked eye as a bright green point attached to the spore. At first the leaf is composed of a compact tissue without Life-History of Isoetes. 247 intercellular spaces, but as it begins to elongate, the cells in- crease rapidly in size, and separating at the corners, numerous intercellular spaces result. There are usually two rows of very large ones (Fig. 49, i) that form broad air-channels extending the whole length of the leaf, but interrupted at in- tervals by layers of cells that form imperfect partitions across them. The primary xylem consists of small spiral and annular tracheids at the base of the leaf, and from these the formation of similar ones proceeds toward the tip. Their number is small, even in the full-grown leaf, and they are the only dif- ferentiated elements of the bundle, which for the rest is com- posed of elongated parenchyma-cells, differing in no essential particular from the original procambium-cells. The Root. — The first root arises from the posterior upper quadrant of the embryo. Ordinarily its axis of growth is in the same plane as that of the leaf, so that a vertical longi- tudinal division of the embryo through the centre bisects both root and leaf (Fig. 39). Not infrequently, however, the root diverges more or less from the median line, and when the leaf is nearly vertical, as sometimes happens, it makes almost a right-angle with it. In the root, as in the leaf, the primary tissues become early differentiated, but here the growth is due exclusively to the activity of cells near the apex. In the very young root (Fig. 27) the end is covered with a single layer of large cells, the dermatogen, continuous with that of the rest of the embryo. Beneath are two layers, con- centric with the cells of the dermatogen (Figs. 27, 28). Of these, the inner is the initial layer of the plerome, which soon becomes well defined and connected with the bundle of pro- cambium-cells in the centre of the embryo. The layer of cells below the primary epidermis is the initial meristem for all of the tissues of the root except the plerome, and the outermost layer of cells (primary epidermis) splits into two layers (Fig. 38, R), that take no further part in the growth of the root. T 248 Campbell.— Contributions to the At a somewhat later stage (Fig. 44) the primary tissue- systems are plainly seen, and are arranged as follows. Occupying the axis of the root is a blunt cylinder whose terminal cells ( x x ) are somewhat larger. This is the ple- rome-cylinder. At the apex the cells are nearly iso-diametric, but lower down become longer and narrower by the formation of longitudinal walls and increase in length due to growth. Covering the apex of the plerome is a single layer of cells, which is the initial for all the other tissues, and this arrange- ment, when established, continues as long as the root grows. From this layer additions are made to the root-cap at regular intervals, and the layers of cells so cut off do not undergo any further division by periclinals, but remain one cell in thick- ness, so that a regular stratification of the root-cap is always noticeable. At the apex of the root there is no distinction between dermatogen and periblem, but these first become separated back of the apex. The primary xylem consists of very delicate spiral tracheids which are formed at the base of the root at the same time that the first ones appear in the leaf. The root grows rapidly in length and bends downward so as to attach the young plant to the ground. It increases but little in diameter, and has fewer and much smaller air-spaces than are found in the leaf. If we compare the structure of the roots with that of other plants, it is found to correspond most nearly with that of certain monocotyledons. Bruchmann1 gives for the roots of the older plant a structure corresponding to De Bary’s 2 third type of angiospermous roots, which differs from the account given here in that there is a special initial layer for dermato- gen and calyptrogen. I have not examined the older roots, and so cannot state whether this is true in the species under consideration or not. The Foot. The foot, which at first projects but little, enlarges as the embryo grows, by the rapid growth of its 1 Jenaische Zeitschr. fur Naturw. VIII. p. 522. 2 De Bary, Comparative Anatomy. Life-History of Isoetes . 249 cells, and encroaches upon the lower cells of the pro thallium, which are destroyed by its growth and their contents absorbed to supply nourishment to the rapidly growing embryo ; and by the time that the young plant breaks through the prothal- lium, and the root reaches the ground, the foot has grown so as to nearly fill the cavity of the spore, and nothing is left of the prothallium except a layer of cells surrounding the central part of the young plant. These cells have now lost their dense contents, and contain little else than a watery cell- sap. Subsequent Growth of the Young Plant. About the time that the young plant breaks through the prothallium, the second leaf begins to develop. The growing- point of the stem (Fig. 45, st) lies in the groove between the base of the root and leaf, and is a nearly flat area, whose surface is nearly at right-angles to the axis of the leaf. The second leaf (L2) arises as a slight elevation on the side oppo- site the first leaf. From the first it consists of several cells, and its growth is entirely similar to that of the first leaf, which it resembles in all respects. The ligule begins to develop while the leaf is still very small. Almost as soon as the leaf can be made out, a line of procambium cells is formed, run- ning from the junction of the first leaf and root and continued into the second leaf as its plerome. As in the first leaf, the apical growth is of short duration, and the subsequent increase in length is mainly due to the rapid multiplication of the cells near the base of the leaf. The growth is slow for a time, but after reaching a certain length it elongates very rapidly, and about this time the first trace of the second root appears. It arises at the base of second leaf in the immediate vicinity of the common fibro- vascular bundle of the stem. A group of cells (Fig. 47, r2) here begins to multiply actively, and very soon shows a division into the initials of the tissue-systems of the young root. As the growing cells of the young root stain more deeply than those of the surrounding tissues, it is distinguishable at a T 2 250 Campbell . — Contributions to the very early stage. Very soon the tissue-systems become differentiated, and the root elongates rapidly and breaks through the overlying tissues. In its structure and growth it does not differ in any way from the first one. The stem has no fibro-vascular bundle apart from the common bundle formed by the coalescence of the bases of the bundles of the leaves and roots. In both leaves and roots there is but a single bundle. This in the leaves is very decidedly collateral in the arrangement of its tissues, with the xylem upon the inner (upper) side. Except for their larger size, and somewhat better developed fibro-vascular bundle, as well as having usually four rows of large air-spaces, instead of two, the full-grown leaves resemble in structure those first formed. The histology of the mature sporophyte was not investi- gated further, as this has already received full attention from other investigators. Owing to the large air-spaces in the leaves, they are much lighter than the water in which the plant grows, so that they finally stand upright, whether their first position was hori- zontal or vertical. In the former case, the apex then appears to be attached laterally, and the apex of the stem is horizontal. Longitudinal sections of young plants with two or three leaves (see Fig. 50) show that the stem has a flat, or slightly con- cave apex which lies at the bottom of a deep cavity formed by the bases of the leaves. The third leaf arises in the same way as the second, and at a point distinctly opposite, i. e. immediately above the first. The development of the young plant was not followed beyond this point, but probably agrees with Hofmeister’s account of /. lacustris \ in which the \ arrangement of the leaves continues up to about the eighth, when it is replaced successively by the J, §, f, x5g, and arrangements. 1 The Higher Cryptogamia, pp. 354-356. Life-History of Isoetes . 251 Summary. The results of the foregoing statements may be briefly summed up as follows : 1. The spores of Isoetes echinospora , var. Brannii , Durieu, will germinate as soon as ripe, provided the sporangium is artificially opened, but germinate more promptly after a rest of several months. 2. The microspores in germinating produce a single pro- thallial cell, and an antheridium composed of four peripheral and four central cells, each of the latter giving rise to a single multi-ciliate spermatozoid, the body of which is derived from the nucleus of the sperm-cell. 3. The ripe macrospore contains a large elliptical nucleus lying in the basal portion. This undergoes division while in its original position, but no division-wall is formed. The secondary nuclei, by repeated divisions, give rise to a number of free nuclei, which lie in the apical region of the future pro- thallium, and not until the number is quite large (about 30-50) does the process of cell-formation begin. 4. The process of cell-formation is entirely similar to that in the embryo-sac of most spermaphytes. It begins at the apex of the spore and proceeds toward the base, following the wall, and finally proceeding centripetally, the whole spore becomes filled with a continuous tissue. 5. The first archegonium arises from one of the first formed cells, at the centre of the apical region. Its de- velopment corresponds closely with that of the Marattiaceae. 6. Other archegonia (usually two) begin to form before the first one is mature, quite independently of its being fer- tilized or not. 7. A small number of secondary archegonia may be formed in case the primary ones all fail to be fecundated, but the total number is small, not exceeding eight in any cases observed. 8. The prothallium is incapable of independent growth, and dies after the supply of food in the spore is exhausted. 252 Campbell— Contributions to the 9. The first wall in the embryo is transverse, but may be inclined to the axis of the archegonium. The lower cell forms the foot ; the upper, stem, leaf, and root. 10. There is usually, but not invariably, a regular division into octants, as in the ferns, and the first divisions in the octants correspond also to the fern-type ; but very early all trace of growth from an apical cell is lost in all the members. 11. The leaf arises from two of the upper octants, the root from the others, the stem arising between them at a later stage. 12. The growth of the root corresponds to that of certain monocotyledons. 13. More than one archegonium may be fertilized, but so far as observed only one embryo develops completely. Conclusions. On reviewing the statements here given, it is evident that Isoetes must still be regarded as holding a very isolated posi- tion among plants ; for while showing evident affinities with several forms, they are in widely separated groups. Vines1 has given a number of reasons for placing Isoetes with the Filicineae rather than with the lycopods with which it is generally associated, and calls attention to several points, i. e. the anatomy and histology of the stem, the multi-locular sporangia, &c., but admits that there are certain difficulties in the way. In certain respects, notably the dichotomy of the older roots, there is a strong resemblance to the lycopods. The secondary thickening of the stem is peculiar among living pteridophytes, with the exception of certain species of Botrychium , but it is of quite a different type from that of gymnosperms and dicotyledons, and approaches more nearly that found in a few monocotyledons. One point overlooked by Vines, and one it seems to me of great importance, is the structure of the spermatozoids. These closely resemble those of the ferns, both in their form 1 Annals of Botany, II. pp. 1 17-2 23. 253 Life- History of Isoetes . and In having numerous cilia. All lycopods yet examined have bi-ciliate spermatozoids like those of the bryophytes. The embryo, too, in the absence of a suspensor common to many, at any rate, of the Lycopodineae, as well as to the arrangement of its members, points to a genetic connection with the ferns rather than the lycopods. Unfortunately we have no account of the young embryo of any of the eusporan- giate ferns, with which Isoetes ought to have a closer connection than with the leptosporangiate forms. Taking into consideration, then, the data at our disposal, the weight of evidence seems to be in favour of regarding Isoetes as belonging rather to the Filicineae than to the Lycopodineae. As to the affinities of Isoetes with the spermaphytes, in regard to the formation of the female prothallium, it more nearly resembles them than it does any pteridophyte with the possible exception of Selaginella\ and in the absence of any distinction between the prothallium proper and endo- sperm, is certainly nearer the spermaphytes than is the former. The reduction, too, of the antheridium, producing but four spermatozoids, is greater than in any other pterido- phyte. The embryo, in the absence of a suspensor, differs very widely from that of the gymnosperms, even the cycads with which Bower1 suggests there may be a relationship, and among the spermaphytes the monocotyledons offer the near- est approach to it in structure. The lateral formation of the stem-apex, as for instance in Alisma (see Goebel, ‘ Outlines/ Fig. 332), is extraordinarily similar to its formation in Isoetes , as well as the relative positions of the single cotyledon and root ; and this together with the histology of the grown sporo- phyte, the leaves with their sheathing bases surrounding the short, bulb-like stem, and the structure of the roots, all suggest a possible relationship to the monocotyledons directly rather than with the gymnosperms. Certainly the develop- ment of the prothallium would hardly be an argument against 1 Annals of Botany, vol. III. No. XI. p. 387. 254 Campbell.— -Contributions to the such a view, as the prothallium of the gymnosperms is quite as highly developed, and in the cycads, at least, capable of independent growth. There is, however, an immense interval between the flower of the simplest angiosperm and the sporophylls of Isoetes, and it would be rash to assume a relationship unless more evidence can be produced on the side of the angiosperms to warrant this. The possibility of an independent origin of the angio- sperms from the pteridophytes has, however, been broached more than once, and further investigations with a view to settling the matter are very much to be desired. Life- History of Isoetes . 255 EXPLANATION OF FIGURES IN PLATES XV, XVI, XVII. Illustrating Prof. Campbell’s paper on Isoetes. All the figures were drawn with a Zeiss camera from microtome-sections mounted in Canada-balsam. PLATE XV. Fig. 1. Cross-section of an ungerminated spore, between the nucleus and the wall, s s1t starch granules ; A l, Albuminous granules. Chromic acid, saffanine preparation, x 650. Figs. 2 and 3. Two sections through the nucleus of the same spore as Fig. 1. n} nucleolus. Figs. 4 and 5. Nuclei of spores that have lain in water, showing the first changes in the nucleus. Chromic acid, gentian- violet, x 650. Fig 6. The primary nucleus undergoing division. P} the cell-plate. Chromic acid, gentian-violet, x 650. Fig. 7. Oblique section through the apical region of a spore having 48 free nuclei, x 300. Fig. 8. Cross-section of the apical region of a spore at the beginning of cell- formation. Chromic acid, gentian-violet, x 650. Fig. 9. A somewhat older stage, in vertical sections, x about 300. Fig. 10. Vertical section through the apex of the young prothallium, showing the mother-cell of the first archegonium (a), x 300. Fig. 11. A few cells from the base of the same. Fig. 12. Vertical section of a prothallium, showing one of the first archegonia, which has failed to be fertilized, x 275 (about). Figs. 13-17. Successive stages in the development of the archegonium. x 600. a, mother-cell ; n, neck-cell ; c, neck-canal-cell (Fig. 14); h, neck-canal-cell (Figs. 15 and 16) ; b, ventral canal-cell; 0, central cell in Fig. 14, mother-cell of egg-cell in Figs. 15 and 16. PLATE XVI. (The arrow corresponds to the axis of the archegonium.) Fig. 18. Open archegonium showing the egg-cell (0) ; r, the receptive spot. X650. Fig. 19. Two-celled embryo in situ, x 300. Fig. 20. Three-celled embryo, x 650. Fig. 21. Eight-celled embryo, median longitudinal section. x6oo. Fig. 22. An older embryo in situ, x 300. Fig. 23. Transverse section of young embryo. x6oo. Fig. 24. Median section of the embryo shown in Fig. 22. Fig. 25. Vertical section of an embryo of about the same age, but showing irregularities in the arrangement of the cells, x 300e Fig. 26. Two vertical sections of an older embryo. X300. 256 Campbell. — Contributions to the Figs. 27 and 28. Longitudinal sections of embryos in which the ligule (x) is beginning to form. Z, leaf ; r, root, x 300. Fig. 29. Four transverse sections of a young embryo, a, nearest the arche- gonium ; d, furthest from it ; II II, the quadrant wall, x 300. Fig. 30. A median section of a somewhat older embryo than 28. b , section of the root of the same, x 300. Figs. 31-35. Five vertical sections (at right angles to the longer axis) of an embryo of about the same age as Fig. 30. Fig. 31 is a median section/ the others through the root, x, the ligule. x 300. Figs. 36-38. Three horizontal sections of a somewhat older embryo ; letters as in the other figures, x 300. Fig. 39. Median longitudinal section of an older embryo, x 300. r, root ; L, leaf; p, foot; x, ligule; v, sheath. PLATE XVII. Fig. 40. Section of the prothallium, with the contained embryo (em). X125. ar, archegonia ; sp, spore-membrane. Fig. 41. Outline of an embryo at the time of formation of the second leaf (Z2), X125. Figs. 42, 43. Two longitudinal sections of the first leaf of an advanced embryo. X300. Fig. 44. Longitudinal section of the root of a similar embryo, x 300. Fig. 45. Apical region of the stem (si) of the embryo shown in Fig. 41. Z1, Z2, first and second leaves ; r, root ; xl, ligule of first leaf ; v, sheath, x 300. Fig. 46. Similar section of a young plant in which the first leaf was nearly full- grown. Letters as before, x 300. r 2, rudiment of the second root. Fig. 47. Section of a somewhat younger plant than that shown in Fig. 46, showing the first rudiment of the second root (r1). Z2, the second leaf, x 300. Fig. 48. Longitudinal section of the young second leaf (Z2) cutting through the second root (r1). The tracheides have already formed at the base of the first root, x 300. Fig. 49. Cross-section near the base of the first leaf of the young plant, showing the intercellular spaces (?) and the second leaf (Z2) and ligule (x) surrounded by the sheath (v) at the base of the leaf, x 300. Fig. 50. Median longitudinal section of a young plant with two full-grown leaves. X125. Pr, Prothallium ; P r 2, roots; Z1, Z2, Z3, leaves; si, stem; sp, spore-membrane ; ar, archegonium neck. tjfnihals of Botany D.H. Campbell del. VoL V7Pl.XV t rfruuxls of Botany D.H. Campbell del. Vol. V,FLXVI. University Press, Oxford. C dnruxZs of Bo tasty Vol. KBl.IV/. CAMPBELL. - ON S 0 E T E S . . 'JIjitulIs of Botany D.H. Campbell del. CAMPBELL. ON 1SOETES. Vol. V, PI. XVIL Fig. 4-1. Fig. 49. Fig. 50. •JbuiaZs of Botany Vol. V.Ph.XVII. Fig. b3. Fig. M University Press, Oxford. Life-History of Isoetes. 257 Postscript. Since the foregoing was written, an article1 appeared in the December number of the Annals of Botany, in which some points considered in my paper were treated, although the major part of the article was concerned with a study of the development of the organs of the mature sporophyte. As I have only considered the development of the oophyte and the embryo, I will only call attention here to that part of Mr. Farmer’s paper that had to do with these. In regard to the sporophyte the only point to be noted is the development of the root. My observations agree with Mr. Farmer’s, except that I am inclined to attribute more than one initial cell to the plerome, and regard the first root decidedly as a primary organ of the embryo, and not as an adventitious one. Concerning the oophyte, there are a number of important particulars in which our results disagree. First : In /. echino - spora the nucleus of the ungerminated spore invariably occupies the basal part of the spore, and not the apex as described by Mr. Farmer for /. lacustris. Second : It was possible, by overstaining with gentian-violet and then withdrawing the surplus stain, to demonstrate the nuclei at all stages of germination. Third : The first stages of germination consist of a division of the nuclei alone. No signs of any formation of cracks in the protoplasm were observed ; division walls first appear after the number of nuclei reaches 30-50. Fourth : The number of archegonia is limited, and the mother-cells are very early differentiated. All the cells of the upper part of the prothallium are not potentially arche- gonium mother-cells. Fifth : There is not necessarily the sharp separation of the vegetative and reproductive portions of the prothallium that 1 On Isoetes laaistris, L ; J. Bretland Farmer, Annals of Botany, vol. V. No. XVII. Dec. 1890. 2 58 Campbell— Life- History of Isoetes . Mr. Farmer asserts for I. lacustris , and this is certainly not determined by the first division of the primary nucleus. This being the case, the comparison he draws (p. 59) between Isoetes and the angiosperms can hardly be maintained. The conclusions as to the affinities of Isoetes are the same, regarding it as belonging rather to the Filicineae than the Lycopodineae. DOUGLAS H. CAMPBELL. Bloomington, Indiana, February , 1891. On Internal Phloem in the Root and Stem of Dicotyledons. BY D. H. SCOTT, M.A., Ph.D., F.L.S, Assistant Professor of Biology ( Botany ) Royal College of Science , London, AND GEORGE BREBNER. With Plates XVIII, XIX, XX. ODERN botanical research, especially during the last IVX fifteen years, has sufficiently demonstrated the im- portance of that modification of the more ordinary type of dicotyledonous structure, which consists in the presence of phloem on the medullary as well as on the cortical side of the vascular bundles. The term bicollateral , now generally used to express this arrangement of the vascular tissues, was first introduced by De Bary1. The structure itself was discovered in Cucurbita by Th. Hartig2 3 in 1854, and by von MohP in the Asclepiadeae and other plants in the following year. From that time onwards internal phloem has been observed in a constantly increasing number of natural orders. Owing chiefly to the investigations 1 Comp. Anatomy of Phanerogams and Ferns; Eng. ed. p. 338. 2 Botanische Zeitung, 1854, P- 51- 3 Bot. Zeitung, 1855, p. 890. [Annals of Botany, Vol. V. No. XIX. August 1891.] 260 Scott and Brebner . — On Internal Phloem of Russow1, Vesque2, Petersen3, and Solereder4, we are now able to form a fair estimate of the distribution of this character among the dicotyledonous orders, though it is almost certain that additions will still be made to the number of those which possess it. Taking Solereder’s summary5 as the latest avail- able, we find bicollateral bundles in the following orders : Polypetalae\ Vochysiaceae,Melastomaceae, Myrtaceae, Lythra- ceae, Onagraceae, Cucurbitaceae ; also in some Combretaceae. Gamopetalae : Asclepiadaceae, Apocynaceae, Solanaceae, Genti- aneae, Loganiaceae ; also in most Convolvulaceae, and in some Acanthaceae. Apetalae\ Thymelaeceae, Penaeaceae, Euphorbi- aceae (sub. tribe Eu-crotoneae, &c.), and in one genus of Poly- gonaceae. In the great majority of these eighteen orders, the character is constant throughout, with the occasional excep- tion of a divergent tribe. For the systematic details Solere- der’s work must be consulted. We have not included the Cichoriaceae and Campanulaceae, in which the nature of the medullary vascular tissues is open to some doubt. Enough has been said to show that bicollaterality is a char- acter widely prevalent among the most highly organized dico- tyledonous families and of great systematic value. It may fairly be maintained, that these orders represent, in certain directions, the most advanced types of dicotyledonous structure. 1 Betrachtungen liber das Leitbiindel- nnd Grundgewebe ; Dorpat, 1875. 2 Anatomie comparee de Tecorce ; Annales des Sciences Nat., Bot. Ser. 6, T. II. 1875. 3 Ueber das Auftreten bicollateraler Gefassbundel ; Engler’s Jahrbuch fur Sys- tematic, Bd. III. 1882. 4 Ueber den systematiscben Werth der Holzstructur bei den Dicotyledonen ; Munich. 1885.' 5 Loc. cit., p. 28. We are not aware of any additions to the list since, unless it be the Basellaceae, a family of climbers allied to the Chenopodiaceae, investigated by Morot and not mentioned by Solereder ; see Morot : Note sur 1’ Anatomie des Basellacees, Bulletin de la Soc. Bot. de France, vol. 31, 1884. Medullary phloem, accompanied by xylem, has further been found by Dangeard in Acanthophyllum (Caryophyllaceae) ; by Robinson in lodes (Phytocreneae), and by ourselves in Acantholimon (Plumbagineae) ; but these formations are allied rather to those in the pith of Tecoma than to the internal phloem of bicollateral bundles : see Dangeard, Monographic anatomique des Acanthophyllum, Le Botaniste, 1889, p. 194; Robinson, on the stem-structure of lodes foment diet, &c., Annales du Jardin botanique de Buitenzorg, vol. VIII. p. 95, 1890. in the Root and Stem of Dicotyledons . 261 The physiological importance of bicollaterality cannot be fully estimated until the general question of the functions of the phloem has been finally determined, but it is undoubtedly great. The sheltering of a portion, often the larger portion, of the delicate phloem within the woody cylinder is an obvious advantage, as is also the fuller utilization of the pith-area and consequent concentration of the tissues generally. It is prob- able also, that the pith-cells themselves may be able to dis- charge both storing and conducting functions more efficiently when brought into direct relation with the phloem and its proteid contents. All such speculations are of necessity premature, but in the mean time the due consideration of these modified arrange- ments may guard us against erroneous views of the functions of the phloem, which might be entertained, if we limited our atten- tion to so-called normal structure. To this point we shall return. The primary object of our work was to investigate the structure of the root in plants, which have bicollateral bundles in the stem and its appendages. Our observation of medul- lary phloem in the root of Strychnos 1 rendered it probable, that in other plants a similar continuity of structure between root and shoot might be traced. In order to estimate the significance of any anatomical character it is evidently necessary to know, whether it extends throughout the plant or is limited to special regions. As regards the more modified dicotyledons, however, our knowledge of their characteristic structure is often confined to the subaerial organs. And if, as we fully expected to find, medullary phloem as such, proved in many cases to be absent from the root, it was still desirable to trace its course in the transi- tional region, and to see whether it ended blindly or became in any way continuous with the normal phloem of the root. This point has been very little attended to by anatomists. Gerard traced the course of the bundles from root to stem in two Solanaceous plants and in Cucurbita. He found that the 1 On the Anatomy and Histogeny of Strychnos , Annals of Botany, vol. III. p. 291, 1889. 262 Scott and Brebner.—On Internal Phloem normal phloem-strands of the root give off branches, some of which pass into the pith and are continuous with the internal phloem of the stem. He figures the transitional region in Datura 1. Fischer described very fully the transition from stem to root in Cucurbita. He shows clearly how the in- ternal phloem of the stem passes to the outside of the primary xylem and for some distance forms a ring between the latter and the secondary wood, gradually disappearing lower down, but long remaining traceable in the medullary rays. His statement that the transitional phloem-ring between primary and secondary xylem ends blindly below, gives, we think, a wrong impression. He purposely limited his investigation to a much thickened axis, and this fact somewhat impairs the clearness of his results2. Lastly Dangeard, who has most recently investigated the mode of union of root and stem, merely states that in the Convolvulaceae the internal phloem accompanies the cotyledonary traces as far as their lower extremity in the hypocotyl, a statement which throws little light on our subject3. Our most interesting information on the roots of plants with bicollateral stem-structure is due to Weiss4, who has shown that in many of these plants, and especially those with fleshy roots, the parenchymatous xylem of the latter contains strands of phloem, produced internally by the cam- bium. This interxylary phloem in the root was found by him in various Onagraceae, Gentianeae and Solanaceae, and he considers it a characteristic peculiarity of plants with medullary phloem in the stem. Our observations extend those of Weiss, and may perhaps throw some further light on the relations between the two 1 R. Gerard, Passage de la racine a la tige; Ann. des Sci. Nat. Bot. Ser. 6, T. XI. 1881, pp. 358, 376, PI. 18, Fig. 54. 2 Fischer, Siebrohrensystem der Cucnrbitaceen ; Berlin, 1884, p. 53, PI. VI. Fig. 14. 3 Dangeard, Recherche sur la mode d’union de la tige et de la racine ; Le Botaniste, vol. I. 1889, p. no. 4 J. E. Weiss, Anat. und Physiol, d. fleischig verdickten Wurzeln ; Flora, 1880 ; Markstandiges Gefassbiindelsystem und Blattspuren ; Bot. Centralblatt, vol. 15, 1883, pp. 397, 409. in the Root and Stem of Dicotyledons . 263 structures. Weiss in his second work lays stress on the distinction between medullary phloem and medidlary bundles. The former is simply the internal part of the phloem in the bicollateral bundles. The medidlary bundles (which possess or may possess xylem as well as phloem) are an independent system and usually represent the lower ends of the leaf- traces, which have already passed down one or more inter- nodes as part of the normal ring. The distinction, plain enough in the extreme cases, is by no means obvious in all, for on the one hand the medullary phloem of bicollateral bundles may be widely separated from its xylem, while on the other hand the medidlary bundles often consist of phloem-strands only. Weiss states that the medidlary phloem as distinguished from the independent medullary bundles may be recognized by the following characters : — 1. The medullary phloem-strands m Solanaceae, Ascle- piadeae, Apocynaceae, Gentianeae, Convolvulaceae, Vochysia- ceae, Cucurbitaceae, &c., in every case accompany the leaf- traces, within which they lie, on their exit into the leaf. 2. They arise almost at the same time with, or only a little later than, the parts of the phloem outside the xylem. 3. Where a cambium forms in connection with them, it never produces wood also, as it does in the medidlary bundles of some of the Cichoreaceae and Campanulaceae, and in Tecoma , Acanthus, &C.1. This last distinction (3) was originally due to Vesque2. It is a merely empirical generalization and, as might have been expected, has proved not to hold good. The other differences are of value, though their application is not always easy. Plants with medidlary bundles in the stem may also have interxylary phloem in the root, as in various Cruciferae (e. g. Cochlearia). In the typical cases each phloem-strand in the root is surrounded by xylem-elements, forming a tertiary concentric bundle. These structures arise at a distance from the normal 1 Markstandiges Gefassbundelsystem. loc. cit., p. 396. 2 Loc. cit. Vesque speaks of false cambium in these cases. See our subsequent observations on Apocynam and Willughbeia . U 264 Scott and Brebner.—On Internal Phloem cambium in the older secondary xylem. Weiss regards them as the direct downward prolongation of the medullary leaf- trace bundles of the stem1. In the course of our work various facts of interest connected with bicollateral structure were observed in the stem as well as in the root, and beyond this, we were led to examine one plant ( Acantholimon ), which does not possess bicollateral bundles in the strict sense at all, though it has analogous peculiarities. Hence, our field of work is not very strictly defined. The present paper is only a beginning of the subject. Many important orders are entirely untouched, and there is clearly room for much further investigation, for which we have already some materials. The following observations then may be grouped under two heads : — 1. The relation between stem and root-structure in plants with bicollateral bundles. 2. Special modifications of the stem-structure in plants, which belong to this category or present a similar arrange- ment of tissues. Observations closely connected with the subject before us will be found in the preceding paper on Ipomoea versicolor 2, which for reasons of convenience has been dealt with separately. We adhere to the term bicollateral bundles in spite of the strong objections to its use which have been urged by Herail. This author rejects De Bary's terminology on the ground that it is only really appropriate to a single family, the Cucurbitaceae. In the majority of the plants in question, he finds that the medullary phloem does not appear at the same time as the rest of the bundle and does not proceed from the same meristem. It is especially on this second point, the independent position of the internal phloem, that he insists. His contention is supported by observations on the Solanaceae, Asclepiadeae, Apocynaceae, Myrtaceae, &c.3 Without entering 1 Markstandiges Gefassbiindelsystem, loc. cit., p. 406. 2 See p. 173 of the present volume of the Annals of Botany. 3 Herail, Etude de la tige des Dicotyledones j Ann. des Sci. Nat. Bot. S£r. 7, vol. II. 1885, p. 267. in the Root and Stem of Dicotyledons. 265 into a detailed criticism of his statements we may admit at once that his view is so far justified, that in many cases the medullary phloem groups show no clear relation, as seen in transverse section, to individual vascular bundles. But their longitudinal course shows sufficiently to which bundle or system of bundles they belong. The term vascular bundle itself does not always or even generally represent a well- defined unit. The idea is taken from certain plants, especially Monocotyledons, in which the strands of associated tracheae and sieve-tubes are really distinct. Botanists have found it convenient to extend the idea to vascular tissue generally, although in a large number of the higher dicotyledons, so far at least as the stem is concerned, the limits between the bundles may be impossible to trace. And so it is with the special case of bicollaterality. So long as an internal phloem- strand has the same longitudinal course as the neighbouring bundles of the leaf- trace there is no serious objection to regarding them as parts of the same formation. We do so, however, rather as a matter of convenience than of principle and without expressing any general opinion as to the order of development, which certainly varies in different cases. I. Relation between Stem and Root-structure in Plants with bicollateral Bundles. 1. Brozvallia viscosa, H. B. and Kth. (Salpiglossideae). The bicollateral structure of the vascular bundles in many Salpiglossideae has been demonstrated by Vesque, Petersen, and Solereder. The two last-named authors have pointed out that this anatomical character, which appears to be constant for the tribe, seems to confirm the opinion of Bentham and Hooker, that these plants belong to the Solanaceae rather than to the Scrophulariaceae. Browallia itself was among the genera investigated by Petersen 1. In the above species, the transverse section of a young 1 Loc. cit, p. 382. U 2 266 Scott and Brebner . — On Internal Phloem stem (in which the secondary wood averages six elements in radial thickness) shows a ring of numerous small groups of internal phloem, each group of about the size of one of the smaller cells of the pith. All the groups lie at some distance within the protoxylem of the bundles, from which they are separated by at least two parenchymatous cells, usually more. The phloem in the pith is collectively greater in amount than that in the normal position. The medullary groups are entirely confined to the outer small-celled zone of pith. In an older stem, with wood about thirty cells thick, the medullary phloem-groups have increased somewhat in bulk, divisions taking place in the adjacent cells so as to add new elements to the phloem. There is, however, no regular internal cambium in this plant and the groups remain isolated. The external phloem receives slight additions from the normal cambium, but its proportion to the internal phloem is little affected. It is worth pointing out incidentally, that the stem has a beautifully clear endodermis with the characteristic dots on the radial walls. This is continuous, through the hypocotyl, with the endodermis of the root. The main root is diarch and shows perfectly typical struc- ture, without any pith (see Fig. 5). Sections of older roots show that secondary thickening goes on in the usual manner. This, then, is a plant in which the medullary phloem of the stem has completely disappeared in the root. It remains to trace its downward course and to determine its relation to the normal phloem-groups of the vascular cylinder of the root. The transverse section of the hypocotyl shows six bundles. Of these, two opposite pairs are the cotyledonary traces (see Fig. 1). The bundles of each pair have their protoxylem-groups turned towards each other. The two remaining bundles, lying between the two cotyledonary pairs, proceed from the leaves above the cotyledons. They dis- appear lower down, anastomosing with the cotyledonary traces. It is the latter only which are directly continuous with the xylem of the root. The pith is small compared to that of the epicotyledonary stem. It contains a number in the Root and Stem of Dicotyledons . 267 (10-12) of phloem groups. Some of these are placed opposite the primary xylem of the bundles, but on the whole there is little regularity. Their distance from the protoxylem-elements also varies, some of the groups lying near the centre of the pith. It is noticeable, that in the hypocotyl the number of internal still exceeds that of ex- ternal phloem-groups, the dimensions of each group being about equal. On tracing the hypocotyl downwards to the tap-root, the changes which we find in the position of the tissues are as fol- lows1 : — The pith gradually thins out ; the two lateral bundles disappear, becoming confluent with those of the cotyledons. The primary xylem-groups of each cotyledonary pair ap- proach each other and ultimately unite, turning their proto- xylem outwards. In the transitional region the strands of internal phloem successively pass out between the converging xylem-bundles and one by one reach the strands of external phloem, with which they fuse. The external phloem-strands concentrate themselves on the two sides of the vascular cylinder, between the two centripetal xylem-groups, which now represent the cotyledonary pairs. Finally, these two groups themselves unite at the centre of the root, forming the diarch xylem-plate, and at this point the last of the internal phloem-strands passes out and joins the normal phloem. So far we have considered the course of the primary bundles without reference to the occurrence of secondary growth. In the upper part of the hypocotyl, the cambium, being formed immediately outside the primary xylem, lies necessarily far outside the internal phloem-groups. Lower down, where some of these groups on their outward course are already level with the xylem, the cambium forms in contact with their outer surface. Then we come to the critical region of transition, where the internal approaches the external phloem, and here it is plain, that for a certain distance the cambium must actually cut through the outgoing strand. Lower down 1 It can. hardly be necessary to explain that the succeeding description relates simply to the course of the bundles and has no reference to developmental changes. 268 Scott and Brebner . — On Internal Phloem still, where the fusion with the external phloem is complete the cambium appears in its typical position entirely within the phloem. The figures i to 5 are selected from a series of 140 suc- cessive transverse sections. Fig. 1 shows the structure of the hypocotyl above the point where the internal phloem has be- gun to pass out, or at least before any of it has passed beyond the primary xylem. In Fig. 2 the pith is already much smaller, and three of the internal phloem-strands are shown on their out- ward course, having already passed the primary xylem-groups1. In Fig. 3 the pith is still smaller, much of the internal phloem has passed out, and one large group is seen imbedded in the secondary wood outside one of the cotyledonary traces. Fig. 4 is from a region, where the minute pith is almost entirely occupied by such internal phloem, as has not yet made its exit. The xylem of each pair of cotyledonary bundles is here united into a single group, and beyond one of the two groups thus formed, a phloem-strand is shown, on its way to join its neighbours outside. Lastly, Fig. 5 shows the typical root- structure. The two cotyledonary xylem-groups here form a single diarch plate. There is no pith, and all the phloem has become external. It will be seen that the sections were taken from a plant, which, though young, already showed some secondary thick- ening. We have stated above, that at certain points of the transitional region the cambium crosses the outgoing phloem- strand. The question arises : does the cambium at these points form lignified secondary wood, so as completely to interrupt the continuity of the internal and external phloem, or does it keep up this continuity by the interposition of secondary phloem-elements? We have no doubt that the latter is the truth. In the sections drawn, some of the ele- ments of the outgoing strand are most probably of secondary 1 It would e just as correct to speak of the xylem passing inwards as of the internal phloem passing outwards, the question being simply one of relative position. The description given in the text is, however, preferable, for the point to be emphasized is the ultimate junction of the internal with the external phloem. in the Root and Stem of Dicotyledons . 269 origin (see for example Fig. 3), and in other cases the im- bedded phloem-group is connected with the cambium by thin-walled tissue, as is shown clearly in Fig. 4. Other sections through the transitional region of an older plant, with a thick zone of secondary wood, showed phloem- groups imbedded in the latter, at a distance from the primary tissues which left no doubt as to their origin from the cam- bium. We conclude, therefore, that the phloem of the root- system remains in permanent, and not merely in transitory, connection with the medullary, as well as with the external phloem of the sub-aerial organs. As regards the main points Browallia may be taken as a type of those plants which have medullary phloem in the stem, but have normal roots. Further information on the points discussed will be found in the paper on Ipomoea versi- color. Our observations agree essentially with those of Gerard, above cited. He traced the transition in the opposite direction namely from root to stem. 2. Asclepias obtusifolia , Mx. The Asclepiadeae are among the plants in which the bicollateral structure is best known So far as the stem is concerned the above species presents nothing remarkable. The internal phloem is in the form of a ring of very numerous groups, which remain isolated from one another. They are not localized exclusively opposite the protoxylem-groups, but also border on the interfascicular tissue. They are generally separated by two or three paren- chymatous cells from the xylem-elements. The internal phloem, although not so great in amount as in some other plants, is extremely well developed, the sieve-tubes and the companion-cells being large and characteristic. There are occasional divisions in the cells bordering on the groups externally, but no considerable cambial increase takes place. Petersen’s1 Fig. 26 (from A. pr triceps') gives a fair idea of the structure of one of these groups, but in our plant there are more sieve-tubes in each. The diameter of a sieve-tube is often as much as ’03 mm. 1 Loc. cit., PI. VII. 270 Scott and Brebner . — On Internal Phloem The external phloem is considerable in amount, but is largely parenchymatous; the sieve-tubes are similar in size to those of the interior, and in a stem 1 cm. in diameter are scarcely more numerous. As regards the root, the early stages are normal, with a diarch or triarch vascular cylinder. But all roots, which attain a diameter of much more than 1 mm. have groups of phloem in the wood. In a root about 3 mm. in thickness, such as that from which Fig. 6 is drawn, much the greater part of the phloem is situated in the wood. In roots of this size periderm has not yet formed, though the external cortex is withering away, and the vascular cylinder forms the bulk of the root. The secondary tissues are extremely parenchymatous and the cells crowded with starch ; xylem- and phloem-parenchyma are quite similar, and the isolated phloem-groups in each arise in the same way by the sub-division of cells cut off respectively on the inner and outer side of the cambium. On the xylem- side the parenchyma consists, partly of the medullary rays, partly of xylem-parenchyma in the narrower sense. Except in the form of the cells, there is no difference between the two, but the phloem-islands appear to be limited to the latter. As regards the distribution of the interxylary phloem, some of the groups are in contact with the protoxylem-elements. These groups have arisen, at any rate in part, from primary paren- chyma. Otherwise the phloem-islands are all secondary. Some of them lie at the sides of the groups of tracheae, which are scattered about among the parenchyma. In this case cambial divisions take place on the side towards the tracheae, and we have the same structure which Weiss figured in Bryonia 1. Other phloem-groups are isolated in the secondary parenchyma re- mote from the tracheae. No considerable cambial growth of the phloem-islands takes place. The neighbouring cells divide and add a few more sieve-tubes to the strand, but there is no obliteration of the older elements. The long-continuing divi- sions show that the development of the phloem-island is a 1 Loc- cit., Flora, 1880, Fig. 6. in the Root and Stem of Dicotyledons . 271 gradual one, and is not completed until the group has been left far behind by the main cambium (Fig. 6). The elements of the phloem of the root resemble those of the stem, but the joints of the sieve-tubes are often very short. The transverse walls both of the external and of the inter- xylary sieve-tubes may be horizontal, bearing a single sieve- plate, or inclined, in which case they show a series of plates. In size the interxylary are quite equal to the external sieve- tubes, both often exceeding “03 mm. in diameter. Roots 1 cm. thick show essentially the same structure. By this time a pericyclic periderm has been formed. The xylem is more parenchymatous than ever. Not only has an immense amount of fresh parenchyma been added by the cambium, but the older parts have undergone dilatation, which starts from several centres and leads to the obliteration of some of the elements. This process is accompanied by the formation of new strands of phloem by the subdivision of cells in the dilated xylem-parenchyma. The interxylary phloem-groups of the root then may arise in three different ways : — 1. By the division of cells of the primary conjunctive par- enchyma. 2. By direct centrifugal development from the cambium. 3. By late division of cells of the older secondary xylem- parenchyma long after its origin from the cambium. We might for convenience distinguish the three varieties as primary, secondary, and tertiary phloem-islands. From what has already been said, it will be clear that the distinction between them is not always quite a sharp one. In the thicker roots horizontal or oblique anastomoses ot the interxylary phloem-strands are often found. The transition from stem to root could only be examined in an old plant, as no seedlings were available. For one or two internodes above the hypocotyl the wood of the stem contains minute phloem-islands. They extend up as far as the wood remains parenchymatous, generally occurring near the groups of tracheae. Careful study of successive sections led to the 272 Scott and Brebner.—On Internal Phloim conclusion that these interxylary phloem-strands end blindly above, and are not continuous in that direction with any of the phloem-systems of the stem. The lower part of the stem is in fact to be regarded as an extension of the storing-tissues of the root, and the phloem-strands may serve for the con- duction of proteid food -materials from one part to the other. Starting from one of the lowest internodes and tracing the tissues downwards the following changes are observed : The wood becomes more and more parenchymatous, i. e. nearly all its elements except the scattered vessels come to have cellulose walls and starchy contents. The interxylary phloem- strands become larger and more numerous. The medullary phloem-strands ramify and at a certain stage are found crowded all over the pith, which gradually becomes smaller, some of them reaching its centre. In the mean time the primary xylem-groups approach the middle of the axis ultimately fusing to form the diarch xylem-plate of the root. Thus some of the medullary phloem-groups, and ultimately all of them, pass to the outside of the primary xylem. There is no doubt, that the more central phloem-groups of the main root are the direct downward continuation of the medullary phloem of the stem1. The process is so far essentially the same as in Browallia . But in Asclepias the medullary phloem does not pass entirely to the outside of the cambium. It passes, in part at least, straight down the root, adjacent to the primary xylem, and thus forms the first ring of phloem-islands. The rest of the interxylary phloem is of secondary or tertiary origin as described above. Some light is thus thrown on the frequency of phloem-islands in the roots of plants with bicolla- teral bundles in the stem. The medullary phloem of the stem becomes the interxylary phloem of the root. The formation of interxylary phloem by the cambium is not a new departure, but an extension of the primary structure. The phloem- strands, whatever their origin, are connected by anastomoses. Our results agree in many points with those obtained by 1 Just as Weiss found in Oenothera , loc. cit. ; Bot. Centralblatt, XV. p. 409. 273 in the Root and Stem of Dicotyledons . Weiss in various Onagraceae, Gentianeae, and Solanaceae1. He, however, found that the interxylary phloem was always formed directly from the cambium, and that the groups never increased subsequently by a special cambium of their own. In Asclepias , as we have seen, phloem-islands may be formed in tissues far removed from the cambium, while the groups constantly show cambial growth themselves, though not on a great scale. The sharp distinction, which Weiss endeavours to draw between his interxylary bundles and interxylary phloem so far falls to the ground. 3. Thladiantha dubia , Bunge (Cucurbitaceae). We take this plant next, because, though systematically so remote from Asclepias , it presents certain analogies with that genus as regards the points under consideration. The bundle-system of the stem is of the usual Cucurbitaceous type and is shortly described by De Bary2. The internal phloem, which is not very greatly developed, is connected with the external mass by sieve-tubes in the medullary rays, as happens in other Cucurbitaceae3. There is a distinct interfascicular cambium4. Some of the roots5 have very curious tuberous swellings, to the structure of which we will return. But first the more ordinary root-structure must be described. The bundle- cylinder is most often tetrarch, but this is not constant, and indeed the same root may pass from hexarch to tetrarch structure in various parts of its course. The roots have no pith, the primary xylem-bundles often meeting in one or two large central vessels. A group of bast-fibres lies outside each of the primary phloem-masses, as in the Leguminosae. As the root grows in thickness the bast-groups break up into a 1 Loc. cit. Flora, 1880, p. 97, and Bot. Centralblatt, XV. p. 408. 2 Loc. cit., p. 248. 3 De Bary, loc. cit., p. 338. We have occasionally found a few small sieve-tubes in the secondary rays also. 4 Cf. M. C. Potter, On the increase of the thickness of the stem of the Cucur- bitaceae ; Proc. Cambridge Phil. Soc. vol. VII. p. 4. 5 Some of the peculiarities of these roots have already been described by Dutailly, Sur quelques phenomenes determines par l’apparition tardive d’elements nouveaux dans les tiges et les racines des Dicotyledones. Paris, 1879, pp. 37 and 39. 274 Scott and Brebner.—On Internal Phloem number of separate strands, as indicated in the diagrammatic Fig. 7. The periderm is pericyclic. When secondary thickening begins, the cambium, as so often happens, forms secondary parenchyma opposite the protoxylem and true wood only opposite the phloem. The parenchyma may either be continued indefinitely by the cambium as a ray, or woody elements may be formed closing It in. As growth in thickness goes on, this process is repeated. New rays originate at the middle of each prominent xylem-mass and these also may be discontinuous, the wood closing in over them. Fig. 7 shows a typical case with the secondary rays only just beginning. In Fig. 8, the secondary ray shown is partly closed in. Considering the position of the parenchyma, analogy has led us to speak of it as forming rays, but when it becomes enclosed in wood the expression xylem-parenchyma would be more appropriate. The normal phloem is well developed, the sieve-tubes attaining the large diameter of ’045 mm. But phloem is also formed on the inside of the cambium. In the earlier stages it is limited to the ray-parenchyma. Some of the interxylary sieve-tubes are always situated at the beginning of the principal rays. Some of these are perhaps of primary origin. Others are scattered about near the sides of the ray. As soon as the secondary rays are started, phloem is formed in them also (see Figs. 7 and 8). Sometimes a nascent ray becomes almost at once enclosed in wood and in these cases the whole of the little parenchymatous group may be used up to form a phloem-strand. Some of the interxylary sieve-tubes are formed directly from the cambium ; others are differentiated later on in tissue which is already remote from it, so that here again the two processes distinguished by Weiss occur in the same root. The interxylary groups are small, in fact a single sieve-tube with its companion-cells is often isolated. The cells surrounding the phloem show a few divisions, but no con- siderable growth takes place in this way in the non-tuberous part of the root. The interxylary sieve-tubes are not so large as the external ones, but reach *03 mm. in diameter. 275 in the Root and Stem of Dicotyledons . The root-tubers grow to an enormous size. They form huge irregularly rounded swellings, which are often between two and three inches (5 to 7*5 cm.) in diameter. The root above and below them is cylindrical and not more than about 5 mm. thick. The root-tubers are deeply furrowed in the longitudinal direction. The furrows, which are usually four in number, correspond in position to the four primary xylem- groups of the root, the ridges between them to the primary phloem. As compared with the ordinary root, the tubers show most interesting changes of structure consisting (1) in increased centrifugal activity of the normal cambium, with production of an excessive amount of parenchyma, the rays bearing a large proportion to the wood ; (2) in enormous dilatation of the pre-existing parenchyma, especially in the region immediately surrounding the primary xylem. This dilatation results in the breaking up of the inner lignified portions of the secondary wood into isolated strands im- bedded in parenchyma. Often the dilatation of the tissues bordering on the primary xylem nips off, as it were, the outer ends of the xylem-plates. Where this happens the protoxy- lem may be carried by the continuous extension of the tissues behind it, far out into the surrounding parenchyma. The result is very curious. In one case two out of the four xylem- plates were unaffected and remained in their original position. In a third xylem-plate the dilatation had separated off the outer part at a rather late stage, so that the protoxylem was only carried a little way out. The fourth protoxylem-group however had been nipped off quite early, and was now stranded in the parenchyma at a distance from the rest of the primary xylem equal to many times the diameter of the original vascular cylinder. During the dilatation every isolated group of lignified tissue forms a centre around which active cell-division goes on, and owing to these local meri- stematic regions the dilated parenchyma loses all trace of its former regular radial arrangement. The growth of the tuber is accompanied by a great increase in the amount of its inter- xylary phloem. The tertiary phloem-bundles are especially 276 Scott and Brebner . — On Internal Phloem crowded around the middle of the root in the region where dilatation has chiefly taken place. They are also massed along the margins of the isolated strands of secondary lignified tissue, but are by no means limited to the neighbour- hood of woody elements. As the dilatation of parenchyma goes on chiefly in the inner part of the root, the outer region of the xylem is the more woody. Here we find, immediately within the cambium, a series of woody wedges (containing the tracheae), separated from each other by broad parenchymatous rays. They are arranged usually in four groups, corresponding in position to the primary phloem-bundles. As the root-tubers increase in thick- ness the course of both xylem- and phloem-strands becomes very oblique, with frequent anastomoses. The development has been traced in detail up to a diameter of about half-an-inch (1*25 cm.). The further growth of the root-tuber appears to be chiefly due to dilatation. Almost the whole tissue in the old specimens is parenchymatous, the wood being almost limited to a narrow zone just inside the cambium. This root shows with remarkable clearness the character- istic changes involved in the assumption of this type of fleshy structure. Complicated as the final condition is, it is easy to refer it to its origin from a comparatively normal dicotyle- donous root-structure. We have not, in this plant, specially investigated the transition from root to stem, but we have no doubt that here, as in Ascleptas, the innermost interxylary phloem of the root is continuous with the medullary phloem of the stem. Altogether this root has much in common with that of Asclepias , the most essential distinction lying in the different relation of the interxylary phloem to the ‘medullary’ rays. Sieve-tubes in the xylem have been observed in the root of Cucurbita by Van Tieghem1 and Fischer2. From the description of the latter they seem to be limited to the transitional region. He regards them as forming the down- ward continuation of the sieve-tubes found in the medullary 1 Ann. des Sc. Nat. Bot. Ser. 5, vol. XIII. p. 215. 2 Loc, cit. , p. 53. 277 in the Root and Stem of Dicotyledons . rays of the hypocotyl. The interxylary phloem-system of Thladiantha is beyond comparison more highly developed a fact correlated no doubt with the presence of the root-tubers. The interxylary phloem in our plant differs from that in Bryonia 1, (i) in the fact that it is in part formed directly from the cambium, (2) in having no constant relation to the tracheae. 4. Ckiroizia pedu7icularis>lAnd\. (Gentianeae). In this genus the existence not only of the medullary phloem, which is usual in the order, but also of phloem-strands imbedded in the wood, was discovered by Vesque2 in 1875. The species observed by him was C. linoides. His observations were extended by Solereder to C. baccifera and to Orphium frutes - cens*. We have been able fully to confirm the statements of these authors in the species examined by us. The medullary phloem forms a ring of scattered strands separated by a few cells (1-3) from the inner margin of the wood. Opposite the larger bundles the phloem-strands may form a double row. The external phloem is not much developed. In a stem, where the secondary wood was quite thirty ele- ments in radial thickness, the normal phloem had received scarcely any increase from the cambium. The groups of sieve-tubes are both smaller and less numerous than those in the pith, and the individual sieve-tubes are also smaller. In the external phloem ’015 mm. is a maximum diameter for the sieve-tubes, while in the internal strands *032 mm. is commonly attained. The examination of sections from near the apex proves that the medullary phloem is formed somewhat later than the external. The first medullary strands to be formed are those just within the large bundles, and here they reach their great- est development. Later on, phloem-strands are also differ- entiated on the inner side of the smaller bundles and the interfascicular tissue. As a rule it is not until two or three xylem-elements have been fully formed in each bundle, that 1 Weiss, loc. cit., Flora, 1880, p. 109. 2 Loc. cit., p. 146, PI. 10, Figs. 3 and 4. 3 Loc. cit., p. 182. 278 Scott and Brebmr.—On Internal Phloem the corresponding medullary phloem-groups arise. Each group is formed by the subdivision of an elongated cell of the young pith, or more than one such cell may take part in the process. Chironia then is a plant to which Heraii’s objection to the term bicollateral would be especially applicable. The internal phloem arises late compared with the rest of the bundle and not, strictly speaking, from the same procambial strand1. But to these differences we are not disposed to attach great importance. The medullary phloem accompanies the bundles on their exit to the leaf and only disappears in the finer branches2. The interxylary phloem-strands begin to be formed when the secondary wood is about fifteen elements thick. They are similar to those in the pith, only more regular owing to their cambial origin. We have satisfied ourselves that Vesque is right in stating that they are developed on the inner side of the cambium, so here we have a case of centri- fugal interxylary phloem as contrasted with the centripetal development in Strychnos. These phloem-islands are formed in great numbers. In a thickened stem the normal phloem is quite insignificant in amount compared to the medullary and interxylary systems jointly. Before we leave the stem it may be pointed out that here also there is a typical endodermis and uniseriate pericycle, both of which are easily recognised even in the thick stems. So far as we know no observations have previously been made on the root of Chironia. A thickened root has the structure represented in Fig. 9. The cortex, which is not thrown off by periderm, is very lacunar ; it shows a distinct exodermis. Its innermost layer, the endodermis, undergoes radial cell-division, enabling it to keep pace with the growth of the vascular cylinder within. The pericycle is one or two layers in thickness. The external phloem is only moderately developed. The xylem-cylinder is dotted over in all parts 1 Our observations on the development of Strychnos may be contrasted with this. See Annals of Botany, vol. III. p. 281, PI. XVIII. Fig. 1. 2 Cf. Weiss, loc. cit., Bot. Centralblatt, XV. p. 401 ■ in the Root and Stem of Dicotyledons . 279 with phloem-islands, which collectively far exceed in area the normal phloem. Of these interxylary strands the more external lie entirely in the secondary wood. Others, however, occur on a level with the primary xylem, and in many roots, though not in all, there is a central phloem-strand occupying the small pith-area. When this is absent the xylem-groups meet in the middle. Tracing the development, we find that the bundle-system is polyarch, the number of xylem- and phloem-bundles variable, often as many as ten of each. For a time the protoxylem-groups alone represent the wood, often with one vessel only to each bundle, the protophloem appearing between them as usual. Later on the centripetal development of the primary xylem goes on, but its inner and later-formed portion is as a rule separated from the protoxy- lem by a few cells, which remain parenchymatous. The further development of the primary xylem is accompanied by the formation of phloem-strands among the lignified cells, so that the more internal phloem is of primary origin. The strands situated on the margin of the primary xylem may subsequently receive additional elements from the cambium (Fig. 10, pA3). The root shown in Fig. 9 has an approxi- mately central phloem-group {ph 2), the origin of which is evidently altogether primary. The secondary thickening of the root presents a striking peculiarity, which has not, so far as we are aware, been noticed elsewhere. In ordinary dicotyledonous roots, as has long been known, the cambium first arises within the primary phloem, by divisions of the cells of the conjunctive parenchy- ma. It then extends round the exterior of the xylem-plates, the pericyclic cells dividing to complete the cambium outside the protoxylem. In Chironia however, the cambium is, as a rule, formed inside the protoxylem-groups, which are thus for a time completely cut off from the rest of the wood. This, then, is the function of the parenchyma, which remains un- lignified between the protoxylem and the more internal wood. It divides to complete the cambial ring (see Fig. 10, px). x 280 Scott and Brebner . — On Internal Phloem As the activity of the cambium goes on, the isolated protoxy- lem-elements are pushed further and further outwards, accompanying the external phloem1. Often this proceeds until a large amount of secondary wood has been formed, as in the root shown in Fig. 9, where two protoxylem-elements are seen outside the cambium. Sooner or later, however, the protoxylem is restored to the main body of the wood, from which the cambium had severed it. Sometimes this happens very soon (Fig. 11), sometimes very late (Fig. 9), and it takes place very irregularly. Thus in Fig. 9, between the two isolated protoxylem-elements is a third, which has long been enclosed in secondary wood. It is difficult to distinguish, but is probably the element marked with letter a. The enclosure of the protoxylem in the. wood happens as follows : the cam- bial divisions within it cease, the cells lying just to the outside begin to divide and complete the cambial ring ; new wood is formed and the protoxylem-element is now left behind, im- bedded in secondary wood (cf. Fig. 11). Ultimately all these elements are thus regained by the wood. As is often the case in roots, the protoxylem-vessels are not spiral but reticu- late. Their thickening is sufficiently different from that of the pitted vessels of the secondary xylem for them to be recognised long after their enclosure in the latter. Since we made these observations we have found the same mode of development in the root of an Impatiens , in which the protoxylem is also cut off by the cambium from the wood. We traced carefully the development of the secondary phloem-islands of the root. Here, as in the stem, they are formed centrifugally, on the inner side of the cambium. A cell cut off from the latter divides two or three times by tangential or inclined walls. The products of division are the mother-cells of sieve-tubes. They then divide again to form their companion-cells and the phloem-strand is complete (see Fig. 12). The development can be studied with advan- tage in radial longitudinal sections, which also leave no 1 It is a curious coincidence, though certainly nothing more, that the same root should show phloem-strands in the xylem and xylem-strands in the phloem. in the Root and Stem of Dicotyledons . 281 doubt that the cambium lies to the outside of the sieve-tubes all through. Chironia and Strychnos are the only genera in which we have at present found strictly medullary phloem in the root, phloem, that is, which lies altogether within the primary xylem. In both cases its presence is somewhat inconstant. On the whole the agreement in structure between root and stem is exceptionally manifest in Chironia . The material at our disposal did not permit of our tracing the actual transition from the one to the other, for all the roots available were adventitious. As regards the connection of these roots with the stem, we found that the interxylary and medullary phloem- strands of the adventitious root are continuous with the inter- xylary phloem of the stem, but there is no direct communi- cation with the medullary phloem of the latter. In Gentiana acaulis , L., which we also examined, the root, though very parenchymatous, showed no internal or inter- xylary phloem. In other Gentianeae, however, peculiarities resembling those of Chironia and Orphium have been observed. Thus Arthur Meyer in his admirable monograph of Gentiana lutea 1 describes sieve-tubes in the secondary wood of both stem and root of that species2. He states that G. punctata, pannonicay and purpurea agree anatomically with G. lutea. In G. cruciata , Jost3 found phloem-strands in the secondary wood of the stem, but not of the root. Weiss also found interxylary phloem in the fleshy roots of some Gentianeae4. It is evident that the anatomy of the order will repay further investigation, especially as regards the relation between stem- and root-structure. We examined a considerable number of other roots of plants with bicollateral bundles, but the results do not call for 1 A. Meyer, Beitrage zur Kenntniss pharmaceutisch wichtiger Gewachse, V. Ueber Gentiana lutea , &c. Archiv fur Pharmacie, 3te Reihe, Bd. XXI. 1883. 2 Loc. cit., pp. 502, 569. 3 L. Jost, Die Zerkluftungen einiger Rhizome und Wurzeln ; Bot. Zeitung, 1890, p. 442. 4 Loc. cit., Bot. Centralblatt, XV. p. 410. No details are given. X 2 282 Scott and Brebner. — On Internal Phloem detailed description. In Oenothera longiflora, Jacq. we were able to confirm Weisses observations as to the presence of centrifugally formed interxylary phloem in the root of this genus1. A large amount of secondary phloem-parenchyma is formed here, but the groups of sieve-tubes are small on both sides of the cambium. In the following bicollateral plants the roots investigated showed external phloem only : — Myrtus mucronatus , Cambess. Ly thrum Graefferi , Ten. Calystegia septum?, R. Br. Apocynum cannabinum , L. W illughbeia fiavescens , Dyer. Willughbeia firma, Bl. Crypto stegiagrandijior a, R. Br. Dischidia nummularia , R. Br. Hoy a pendula, Wight et Arn. Periploca graeca, L. Daphne Mezereum , L. In all these cases it is probable that the transition from stem to root takes place as in Ipomoea and Browallia , and that the medullary phloem of the stem is continuous with the external phloem of the root. Our conclusions as regards the roots may be summed up as follows :■ — 1. The majority of the plants examined with bicollateral bundles in the stem showed normal structure of the root, the medullary phloem (to judge from the cases specially investi- gated) turning outwards in the hypocotyl with the protoxylem- groups. It is thus continuous with the external phloem of the root-system. 2. A certain number of roots among the plants in question have interxylary strands of phloem. These may be (a) primary , (b) secondary, or (c) tertiary. The first, as regards the main root, form the direct downward prolongation of the medullary phloem of the stem, the phloem-strands running down through the wood, instead of turning outwards to join the external phloem. The secondary interxylary phloem, which may be limited to the root or extend also into the stem, is in the plants here described formed centrifugally, on 1 Loc. cit., Flora, 1880. 2 Cf. however the paper on Ipomoea versicolor L Scott, Ann, of Bot No. XVIII. in the Root and Stem of Dicotyledons. 283 the inner side of the cambium. The tertiary strands are differentiated from the older secondary woody parenchyma, when already remote from the cambium, and are especially characteristic of fleshy roots. Intraxylary (medullary) phloem has so far only been found in the roots of Strychnos and Chironia . II. Special modifications in the structure of the Stem. We are not aware that any cases have hitherto been recorded of the formation of medullary wood by an internal cambium in plants with undoubtedly bicollateral structure of the bundles. As was pointed out in the intro- duction, Weiss, in agreement with Vesque, has made the constant absence of medullary wood a criterion by which the internal phloem of bicollateral bundles can be distinguished from that which belongs to an independent bundle-system in the pith (e. g. Tecoma). On this ground, among others, Weiss has removed the internal phloem of certain Cichoriaceae, Campanulaceae, and Acanthaceae, from the former to the latter category1. We have found, however, that in some plants with typical bicollateral structure a true internal cambium is active, producing new wood as well as new phloem, the orientation of the two being inverted as compared with the normal parts of the bundle. 1. Apocynum cannabinum , L. The Apocynaceae are enu- merated by Vesque, De Bary, Weiss, Solereder, &c. among plants characterized by bicollateral structure of the bundles, and the character is here of ordinal value. The above species (the so-called ‘Indian Hemp’ ) is thoroughly typical in this respect. The internal phloem is developed from the procam- bium simultaneously with the xylem and external phloem, and from the first exceeds the latter in extent. It lies close to the protoxylem-groups of the bundles, only one or two 1 Loc. cit, Bot. Centralblatt, XV. pp. 321, 396, &c. 284 Scott and Brebner . — On Internal Phloem parenchymatous cells intervening between the primitive tracheae and the nearest internal sieve-tubes. It is not until the stem has attained a considerable thickness that any departure from ordinary bicollateral structure begins. At the stage shown in Fig. 13, the normal wood has a radial thickness of from seventy to ninety elements. The very characteristic internal phloem forms a ring, which is not how- ever continuous but is broken up into groups by narrow radial strands of parenchyma from one to three cells wide. Often, but not always, these rays correspond to the primary medullary rays of the normal wood. Not only is the internal greater in amount than the external phloem, but its individual elements are also larger. The internal sieve-tubes often reach *03 mm. in diameter, while the normal ones scarcely exceed *02 mm. In some places an internal cambium has appeared, which at one or two points, opposite the protoxylem of the larger bundles, has begun to form tissue on its outer side. This tissue is the internal centripetal wood. The cambial divisions begin in the parenchymatous cells im- mediately bordering on the outer edge of the phloem. Thus the internal is separated from the normal wood by one or two layers of thin-walled cells. The first xylem-elements formed are lignified parenchyma. The internal cambium soon extends all round the pith, but its production of wood is for a long time limited to the regions where it first started. Elsewhere its activity is limited to the formation of additional phloem on its inner face. When the normal wood is from 130 to 150 cells in radial thickness the internal woody masses are about fifteen cells thick (Fig. 14). At a still later stage the internal wood becomes much more extensive. In the oldest stem at our disposal, about 1*4 cm. in diameter, it forms eight masses, which together occupy the greater part of the circumference of the pith. These masses lie opposite those parts of the normal wood which are richest in vessels, or, in other words, the internal wood still shows a relation to the primary bundles. Its maximum thickness now in the Root and Stem of Dicotyledons . 285 amounts to twenty-five elements, equal to about one-eighth of the normal wood. The internal cambium forms most phloem where it does not produce any wood. Opposite the woody groups the number of phloem-elements is smaller and they also undergo greater compression (see Fig. 14). The internal centripetal wood, where it is well developed, consists of elements of three kinds: (1) fibrous cells with pointed ends which form the small lumina seen between the larger elements in transverse sections (Fig. 14) ; (2) xylem- parenchyma, and (3) ray-parenchyma. The internal xylem- rays resemble those of the normal wood, but their cells are less elongated radially. All the elements have lignified walls, and simple elliptical pits, which in the fibrous cells are spirally arranged. The internal wood chiefly differs from the external in the absence of vessels. It may be added that the internal sieve-tubes are of perfectly typical structure, with lateral sieve-fields as well as transverse plates, which form callus in autumn. The pith is very lacunar and offers comparatively little resistance to the growth of the internal vascular tissues. 2. Willughheia firma , Bl. (Apocynaceae). This climbing representative of the order shows the same structure as Apocynum cctnnabinum , namely centripetal internal wood, but in a still more striking form, for in Willughbeia the internal wood contains large vessels. Its development begins here even later than in Apocynum. When the normal wood is on the average about eighty cells in radial thickness there is still no sign of internal xylem. The inner phloem-groups form a ring, and are only separated from one another by narrow rays of parenchyma. There is already an active internal cambium which has arisen by division of about the third layer of parenchymatous cells within the protoxylem, and has added largely to the phloem, so that the older phloem-elements and some of the pith-cells also are becoming crushed and obliter- ated. The pith contains very large thick-walled sclerenchy- matous fibres, and also large laticiferous cells. As the inward growth of the internal phloem continues, the rays keep pace 286 Scott and Brebner . — On Internal Phloem with it, chiefly by extension of their cells without division. The internal sieve-tubes are usually about *025 mm. in diameter, and have very abundant proteid contents. Besides the typical phloem-elements, the internal groups, like the pith, contain septate crystal-sacs, such as are also found in the normal external phloem. The two phloem-systems are about equal in extent. The internal ring has the advantage in radial thickness (which amounts to ten elements), but this is balanced by the greater periphery of the external phloem. In an older stem, in which the normal wrood has about 140 elements on the radius, the centripetal xylem has appeared. It is formed in irregular groups, one of which is shown in Fig. 15* The elements of this internal wood are (1) vessels with bordered pits, composed of long joints, and reaching *04 mm. in diameter (about half that of the largest vessels of the normal wood) ; (2) xylem-parenchyma, and (3) radially elon- gated cells which may be regarded as forming xylem-rays. The centripetal wood, which is entirely produced by the internal cambium, is therefore of perfectly typical structure. The parenchyma, lying between the outer margin of the centripetal wood and the protoxylem, becomes partially lignified. In one case we found reticulated elements, probably vessels, in this position. In the older stems the greater development of the internal vascular tissues has necessarily produced increased obliteration towards the pith. Many of the older sieve-tubes have very callous plates. 3. Periploca graeca , L. (Asclepiadeae). In this plant there is a very distinct internal cambium, which produces a large amount of secondary phloem towards the pith. It also occasionally forms a few lignified elements in centripetal direction, but in the stems investigated the amount of internal wood was insignificant. The cases of Apocynum and Willughbeia are sufficient to invalidate the generalization of Vesque and Weiss that the inner cambium of bicollateral bundles is a ‘false’ cambium in the Root and Stem of Dicotyledons ; 287 capable of producing phloem only without wood. All such arbitrary limitations of the possibilities of dicotyledonous structure are rash. Until Sanio’s discovery in Tecoma , no one would have suspected the existence of medullary cambium at all. Now we know that it is of common occurrence, and that whether it be connected with bicollateral or with inde- pendent medullary bundles, it is alike able to form xylem or phloem or both, according to the special requirements of the plant. The only safe generalization as to cambium is that it may arise in any living tissue, to whatever 'system’ this may belong, and that it is capable of producing any form of tissue for which at the moment the plant has an increased demand. 4. Gentiana acaulis , L. Our observations on this plant, to which reference has already been made, may be described very shortly, for they are in close agreement with those of Meyer and Jost, above cited, on other species of the genus. In the stem of this species the bulk of the phloem is internal. Its arrangement is unusually complex. In the older inter- nodes we find two concentric rings of internal phloem-groups, in addition to which there is often a third set lying quite in the middle of the pith. At first sight one is disposed to regard these strands as forming an independent medullary system, but investigation of their longitudinal course shows that this is not so, but that all the internal strands are branches from the inner phloem of the bicollateral bundles, so even in this extreme case we see no sufficient ground for departing from De Bary’s terminology. The main bundles of the leaf are bicollateral. The leaves themselves are opposite, decussate, and sheathing. Three bundles enter the stem from each leaf, but fuse into one broad bundle before turning down into the internode. The fused bundle runs down through two internodes, its elements spread- ing themselves out tangentially 1, and ultimately joins the outgoing bundles of the leaf vertically beneath, i. e. at the 1 As Meyer says of G. lutea , the elements separate so widely that one can no longer speak of the course of the bundles, but only of the connection of the elements, loc. cit., p. 501. 288 Scott and Brebner . — On Internal Phloem second node below. The internal phloem accompanies the leaf-trace bundles into the stem, and runs straight down through two internodes, where it joins that of the next bundle vertically beneath. It is usually at this point that branches arise which penetrate somewhat more deeply into the pith, while those which reach the middle of the stem are given off lower down still. Hence as a rule the transverse section of the youngest internodes shows a single ring of internal phloem-groups, a rather older part has a double ring, while the more central groups arise by the division of pith-cells at a comparatively late stage. But there is no great constancy about this and occasionally the more internal branches arise much earlier. The different strands are further connected by anastomoses1. We may add that sometimes phloem-groups are formed outside the protoxylem elements, between these and the rest of the wood. This is an approach to the forma- tion of interxylary phloem-islands, as in some other Gentians, Chironia , &c. We have described the distribution of the phloem in this plant because it shows an extreme modification of ordinary bicollateral structure, and yet is readily referable to the type. It may be added that the external phloem-groups are also very scattered and widely separated from the xylem, so that there is a certain analogy between the two systems as regards distribution. We pass over our other observations on plants with strictly bicollateral bundles, as they present no new points of importance, and go on to a plant the remarkable structure of which is only indirectly connected with our main subject. 5. Acantholimon glumaceum , Boiss. (Plumbagineae). The anatomy of this genus has already been the subject of several investigations, the earliest of which is due to Prof. Oliver2, who especially insists upon the absence of typical medullary rays. He also observed and figured among other peculiarities the 1 Cf. Meyer, loc. cit., p. 502 ; and Jost, loc. cit., p. 439. 2 D. Oliver, On the structure of the stem in certain species of Caryophylleae and Plumbagineae ; Trans. Linnean Soc. vol. XXII, 1859. in the Root mid Stem of Dicotyledons . 289 occurrence of concentric belts of parenchyma in the wood, Kruger 1 confirmed Prof. Oliver’s results as to the medullary rays and was the first to discover concentric bands of typical phloem in the wood. This remarkable anomaly he was inclined to refer to the action of successively renewed cambial layers. Lastly, Solereder2 confirmed Kriiger’s discovery, and found, in the occurrence of tangential divisions between the xylem and interxylary phloem-zones, a clear proof that the wood as a whole (Holzkorper) owes its origin to the appear- ance of successive cambial layers. Both he and Kruger, how- ever, recognise the possibility that the interxylary phloem might arise as in Strycknos, i. e. as De Bary erroneously sup- posed to be the case in Strycknos. On this view the inter- xylary phloem would be formed centrifugally on the inner side of the cambium. We proved in our former paper3 that the phloem in the wood of Strycknos is developed centripetally, and it was the apparent analogy of structure between that genus and Acantholimon , which led us to examine the latter. Some divergences in detail, between our observations and those of previous writers, may well be due to specific differences. Acantholimon glumaceum is well known in gardens as a rock-plant. Its habit is not unlike that of its British relation, Armenia vulgaris . The latter, however, does not share its anomalies of structure. The diagrammatic transverse section (Fig. 16) will give a sufficient idea of the extraordinary structure of a thick stem. In order to understand the complicated conditions at maturity, it will be necessary to trace the development. The young stem has a perfectly normal structure. The bundle-ring is interrupted by several (usually 3-5) broad radial strands of parenchyma. The tangential section shows that each of these rays occurs immediately above the exit of a leaf-trace bundle. We do not see that they differ essentially from the primary medullary rays of other stems, which in all cases are 1 Otto Kruger, Beitrag zur Kenntniss der sogenannten anomalen Holzbildungen. Dissertation. Leipzig, 1884. 2 Loc. cit., Iiolzstructur, p. 164. 3 Annals of Botany, vol. III. 290 Scott and Brebner . — On Internal Phloem the spaces -(filled with parenchyma) between the bundles, and must therefore have a definite relation to the bundle-system. In this plant, and in many others, the outgoing bundle leaves, as it were, a parenchymatous space above its exit, which is only closed over further up by the converging bundles on either side. This space is the primary ray. In Acantholimon there is no interfascicular cambium, the ray following the growth in thickness by extension of its cells, perhaps accompanied by a few irregular divisions. No secondary rays are formed at any stage which has come under our observation. A normal fascicular cambium is formed between xylem and phloem and for some time the thickening goes on in a perfectly typical way. The annular and spiral vessels of the primary wood are succeeded by a secondary xylem, which is especially rich in vessels. These are of two kinds : large vessels with bordered pits, and much smaller ones with a con- spicuous spiral thickening and small pits between the coils. The closely packed elements with lignified thickened walls, which in a transverse section might easily be taken for woody parenchyma, are in reality these small vessels. The parenchyma, which is scattered among them, is entirely thin- walled and usually unlignified. In addition to these elements, the secondary wood contains scattered strands of fibres thickened so that the cavity has all but disappeared. The larger vessels occur in rather regular concentric layers. The phloem is very thick. It consists of elongated cells equivalent to phloem-parenchyma, but prosenchymatous in shape, of sieve-tubes, with inclined terminal sieve-plates, and their companion-cells. The first anomalous formations generally appear in stems about 2 mm. in diameter, where there is a wide zone of secondary wood and the outer cortex has been already cast off by periderm. The first departure from normal structure consists in the appearance of an internal cambium. This has not hitherto been observed. The cambial divisions may occur immediately within the protoxylem of the bundles in the outermost small-celled tissues of the pith, but in other in the Root and Stem of Dicotyledons. 291 cases they occur in the parenchyma of the bundles themselves outside the protoxylem, so that the latter is cut off from the body of the wood1. The internal cambium at once begins to form centripetal wood on its outer surface and internal phloem towards the pith. If the cambium has cut off the protoxylem the latter is necessarily carried inwards towards the centre of the pith in front of the advancing phloem. Figs. 17 and 18 show the more normal type, where the cambium arises within the protoxylem. The difference is of no impor- tance whatever, as regards the final result. The medullary formations are localized opposite the bundles ; sometimes there is one internal strand to each bundle, sometimes there are two. Both internal wood and phloem agree exactly in structure with the normal tissues. In the former, the rela- tively large vessels are conspicuous. The secondary forma- tions encroach very seriously on the pith. We have found the internal wood as much as twenty-five elements in radial thickness ; the phloem is generally less extensive. It is quite possible that the internal cambium may at first be continuous with the normal cambium at the nodes, as Robinson found to be the case in lodes tomentella'2, , but we have no proof of this. The formations in Acantholimon bear a close resem- blance to those observed by Robinson. The similarity with Tecoma is more superficial, for in this latter plant a medullary phloem-strand is present before the cambium appears, which is not the case here. In Acantholimon the internal wood and phloem are entirely secondary, and it would be a forced view to regard them as forming part of the leaf-trace system. The curious structure described by Dangeard ( lx .) in Acanthophyl - him has some analogy, but differs in the fact that the cam- bium completely surrounds the wedges of wood, which we have never found in Acantholimon. We suspect that the anomaly discovered by Morot in the Basellaceae is more nearly related to the present case than to ordinary bicollateral structure. 1 This process is comparable mutatis mutandis to the mode of origin of the normal cambium in the root of Chironia. 2 Loc. cit. 292 Scott and Brebner . — On Internal Phloem In the mean time other anomalies have made their appear- ance. At a certain point in the development, in some cases, when the normal wood has only twelve cells on the radius, in others, when it has formed from thirty to forty layers, inter- xylary phloem appears. In one specially instructive case the thickening was very eccentric : on one side the wood and bast were normal, on the other side the wood was much thicker and traversed by two tangential bands of interxylary phloem, each of which had a cambium on its inner side (cf. Fig. 19). In this stem, the first interxylary cambium of the anomalous part exactly fitted on to the external cambium of the normal portion. We call attention to this exceptional case, because it throws light on the origin of the concentric zones. As a rule, the thickening is approximately uniform round the whole circumference. The bands of interxylary cambium and phloem sometimes run completely round the stem interrupted only by the parenchymatous rays. But more often their arrangement is less regular, the number of concentric bands varying not only in the different woody wedges, but also within the same wedge. The general arrangement of the tissues is such, that the inner layer of each concentric zone of xylem contains the larger vessels. Its outer portion is formed of the densely packed smaller vessels with thin-walled parenchyma interspersed (Fig. 19). The wider phloem-zones have precisely the same structure as the normal external phloem (Fig. 20). The sieve-plates in autumn are often callous. The narrower zones of thin-walled tissue are occasionally destitute of sieve-tubes, consisting only of cambium on the inner and thin-walled phloem-parenchyma on the outer side. But this is exceptional and, as a rule, the interxylary zones consist of typical phloem. The interxylary cambium which always lies on the inner side of the phloem band, does not appear to be very active, for no crushing to speak of takes place. The radial rows of the interxylary phloem are continuous inwards (through the cambium), but not outwards, with those of the wood. There can be no doubt that the development of these phloem-bands is centri- in the Root and Stem of Dicotyledons « 293 petal (cf. Figs. 19 and 20). The only satisfactory explanation of the whole structure is that we have here to do with successive layers of extrafascicular cambium. For a time the normal cambium continues its activity as in ordinary Dicoty- ledons. Then a new cambial layer is formed by division of the cells of the pericycle or of the outer phloem-parenchyma. This layer may be continuous (except in the rays) all round the stem, or it may be partial, abutting at either end on the normal cambium. The new layer forms wood internally and phloem externally, so that the original cambium and phloem become enclosed, and so the first interxylary zone is formed. After an interval the process is repeated. The first extra- fascicular cambium is replaced by a more external layer, and so another complete or partial phloem zone is left behind and becomes imbedded in the wood. This process may take place over and over again, until we have the complicated structure of an old stem, as shown in the diagram (Fig. 16). As we have already seen, each enclosed cambium retains something of its activity and does not itself pass over into permanent tissue. These are conclusions, which we have drawn from the careful comparison of many stems, but we have not yet been so fortunate as to observe the first origin of a new cambial layer. Possibly the first extrafascicular cambium may arise in the pericycle, certainly the later ones are formed from the phloem-parenchyma. In the exceptional cases, when the interxylary zones have no sieve-tubes, we may assume that this new cambium arose very near the old, so that the differentiation of the products of the latter remained incomplete. Occasionally small round bundles are seen in transverse sections imbedded in the wood, just outside an interxylary zone. These are leaf-trace bundles on their very oblique out- ward course, which have become enclosed by extrafascicular cambium. The adventitious roots have a normal structure. Our conclusions as to Acantholimon are as follows: — 1. An internal cambium is formed at a late stage, either 294 Scott and Brebner . — On Internal Phloem just inside or just outside the protoxylem. It produces a large amount of medullary wood and phloem, with inverted orientation. 2. The concentric bands of phloem and xylem, of which the secondary tissues are composed, are due to the activity of successive cambial layers, as was conjectured by Kruger and Solereder. Conclusion. In concluding we wish to point out the bearing of our subject on a theory which has been recently put forward as to the function of the phloem in general. In opposition to the prevailing view that the phloem is primarily the conducting tissue for the nitrogenous, and especially for the proteid, food-substances of the plant, Prof. Frank1 and Dr. Blass2 maintain that the phloem is essentially a store-tissue for the benefit of the wood. Prof. Frank says3 : ‘ The position which this tissue invariably ^occupies speaks most clearly for its function as a store-chamber of those substances which the cambial layer requires for the formation of the wood ; for in all fibrovascular strands it is a faithful companion of the woody bundles, and it increases and dimin- ishes in amount with the bulk of the woody bundle which is to be formed ; it is constantly situated immediately outside the cambial layer ; it forms an annular zone around the cam- bial ring where the latter surrounds a closed cylinder of wood, as in most dicotyledonous stems and trunks ; it forms an isolated strand, placed exactly in front of the woody bundle with its cambium, when we have to do with isolated fibrovascular-strands, as is especially the case in the petioles and ribs of the leaf.’ Dr. Blass, who worked in conjunction with Prof. Frank, expresses his views as follows : ‘Just as the contents of the starch-sheath serve to build up the bast-cells, 1 Lehrbuch der Pflanzenphysiologie, 1890. 2 Untersuchungen iiber die physiologische Bedeutung des Siebtheils der Gefass- biindel ; Pringsheim’s Jahrbiicher, Bd. XXII, 1890. 3 Loc. cit., p. 162. in the Root and Stem of Dicotyledons. 295 so the contents of the phloem are chiefly conveyed to the cambium in order to be employed in the activity of this meristematic zone and in the building up of the xylem1.’ As evidence for this view, Dr. Blass, who has worked out the theory in detail, brings forward the facts that in trees the sieve- tubes nearest the cambium are richest in proteid contents ; that in some cases the contents of the phloem accumulate in autumn and are diminished when growth is renewed in the spring ; that in some plants with reduced xylem ( Drosera and certain aquatics) the sieve-tubes are rudimentary, containing nuclei and even chlorophyll-granules ; and lastly that in the ringing experiments so often quoted in support of the prevail- ing views, the excessive growth above the incision is due simply to the formation of ‘ wound- parenchyma,’ and not to the interruption of the downward current of food-material. In support of this contention, Dr. Blass states that the phloem below the wound shows no diminution of its contents. We purposely avoid criticising Dr. Blass’s arguments, though it appears to us that his results are not inconsistent with the theory of conduction and in some points even lend it additional support. We willingly admit that in all plants with cambial growth the supply of food-materials for such growth must be an important function of the phloem. Nor are we aware that this has ever been denied. But we wish to point out that the anatomical relations of the phloem are often quite inconsistent with the supposition that its exclu- sive or principal function is connected with the formation of wood. In all the numerous plants which have bicollateral bundles or an analogous arrangement of tissues, a great part of the phloem, often the greater part and sometimes nearly the whole, is placed in that region of the stem where no formation of wood is going on, in a position as remote as possible from the wood-producing cambium, for the rare exceptions in which some internal wood is also formed may here be left out of consideration. Yet this internal phloem is absolutely 1 Loc. cit., p. 258. Y 296 Scott and Brebner . — On Internal Phloem typical in structure and contents. Nor is it a merely transi- tory tissue. Long after it is cut off from the normal cambium by a broad zone of secondary wood, it goes on increasing, often to a much greater extent than the normal external phloem. In many of these plants it is the latter, the phloem in contact with the wood-producing cambium, which is tend- ing to become rudimentary, while the internal phloem, remote from the cambium, is abundantly developed and retains all its typical characters. That the internal, like any other phloem, indirectly supplies the cambium as well as other growing regions, we do not for a moment doubt, but this is simply to say that it is a conduc- ting tissue. So too with the ‘phloem-islands.’ In plants like Strychnos or Salvadora these are no sooner formed than they become imbedded in the dense wood, and are cut off from all direct communication with the cambium. It would be easy to cite other examples, as the stem of the Chenopodiaceae and many allied orders, in which almost all the phloem is deeply imbedded in the fully formed wood, or the Monocotyledons generally, where the closed bundles retain a typical and active phloem for months or years after all formation of wood has been completed. In the light of facts such as these we cannot but think that the view of Prof. Frank and Dr. Blass depends on too one-sided a consideration of typical dicotyledonous anatomy. The passage quoted above from the former author, as well as Dr. Blass’s concluding statement that ‘ a typical condition of the sieve-tubes is only to be found where wood-elements are to be formed V seem to us not to be justified by facts. Our results as to the continuity of the various phloem-systems in root and stem tend to give further anatomical support to the theory of the conducting functions of this tissue, a theory which, as we need hardly point out, is fully consistent with the view of Prof. Sachs that the phloem may also be the seat of proteid-formation. 1 Loc. cit, p. 290. in the Root and Stem of Dicotyledons. 297 We are indebted for our material partly to the Director of the Royal Gardens, Kew, partly to Mr. H. N. Ridley, of the Botanic Gardens, Singapore, who has been so kind as to send us a number of specimens carefully preserved in spirit. We have further to thank the officers of the botanical department of the British Museum, and also Mr. B. Daydon Jackson, Sec. L. S., for their kind help in the nomenclature of species. POSTSCRIPT. When this paper was completed in December, 1890, we had not seen the work of M. Lamounette, f Recherches sur Forigine morphologique du liber interne/ which appeared in November, in the Annales des Sci. Nat., Bot. Ser. 7. T. XI. M. Lamounette has made a number of valuable observations on the origin of internal phloem in the hypocotyl, the cotyledons, the terminal bud of the stem, and the leaves. He strongly supports the views of M. Herail, and rejects the term ‘ bicollaterality ’ in all cases, even in the Cucurbitaceae (p. 264). He regards the internal phloem as being due to an ulterior evolution of the medullary cells, ana- logous to the formation of periderm in the cortex (p. 235), and considers that it was primarily independent of the normal bundles, its close association with them in the Cucurbitaceae not having been attained at a later phylogenetic stage. His view of the internal phloem as an 1 acquired character ’ which has become heredi- tary (p. 278) is evidently beyond criticism in the present state of our knowledge. As regards the transition from stem to root, M. Lamounette says that the internal phloem, when present in the hypocotyl, is altogether formed in the medullary parenchyma, and not in any degree at the expense of the phloem of the root (p. 277). He appears to attribute the opposite view to Gerard. Surely there is some confusion between course and development here. In the cases investigated by Gerard and by ourselves there is no doubt as to the continuity between the internal phloem of the hypocotyl and the external phloem of the root, but no one has ever supposed that the one is developed from the other. M. Lamounette appears to have overlooked this continuity in all cases, a fact which is probably explained by his having worked chiefly with very young seedlings. He rightly points out that the development of the internal phloem in the hypocotyl often takes place very late as is especially the case in Ipomoea (p. 243). In the Onagraceae he finds that in- ternal phloem is entirely absent from the hypocotyl, the cotyledons, and even the earlier-formed leaves (pp. 245 and 274). So far as the hypocotyl is concerned this can only be true of very young plants, for we know from Weiss’s observations above cited that the internal phloem is here continued into the root, when it forms the innermost interxylary phloem-strands (see above, p. 272). We suspect that in all cases continuity between the internal phloem of the stem and the phloem of the root exists, though the connection may no doubt be established relatively late in some cases. 298 Scott and Brebner. — On Internal Phloem M. Lamounette’s careful observations on the origin of the internal phloem in the growing point of the stem are of great interest. He finds that it always arises later than the normal tissues of the bundle, and that it is of medullary, not of procambial origin. The distinction in some cases is certainly a very fine one, and we have not always been able to detect it, but we willingly accept M. Lamounette’s results. We hope that our further investigations may throw additional light on this author’s interesting hypothesis that the phylogenetic origin of all internal phloem is to be traced to independent medullary strands, unconnected with the normal bundle- system. Two other papers have lately appeared, bearing on our subject. Leonhard’s Beitrage zurAnatomie der Apocyneen (Bot. Centralblatt, Bd. XLV, 1891) confirms the general occurrence of internal phloem throughout this order (with one doubtful exception). The author appears to have found phloem embedded in the wood in Lyonsia , though his description is not perfectly clear, as he does not distinguish between interxylary and intraxylary phloem. Quite recently M. Herail has published a preliminary note on medullary phloem in the root (Comptes Rendus, April 13, 1891). He has discovered this structure in the adventitious roots of Vinca major and V. media , but not of V minor , in which the pith soon becomes sclerotic. He points out the necessary condition on which the occurrence of medullary phloem in the root manifestly depends ; namely the presence of a permanently parenchymatous pith. He cites Van Tieghem’s observation of internal phloem in the root of Cucurbita , but is not acquainted with our description of this tissue in the root of Strychnos, published in 1889. M. Herail’s observations are a welcome addition to our own. D. H. S. & G. B. in the Root and Stem of Dicotyledons. 299 EXPLANATION OF FIGURES IN PLATES XVIII, XIX, XX. Illustrating Messrs. Scott and Brebner’s paper on Internal Phloem. The following lettering is used throughout : — cb1 — normal cambium. cb2 — medullary cambium. cb3 -- extrafascicular cambium. phl = normal external phloem. /A2 = medullary phloem. ph3 — phloem-islands, imbedded in the xylem. x1 = primary xylem. x2 = secondary xylem. x3 = centripetal xylem, formed by medullary cambium. px = protoxylem. pc = pericycle. e = endodermis. Figs. 1-5, Browallia viscosa. The line C-C1 is the plane of the cotyledons. Fig. 1. Transverse section of hypocotyl. Numerous groups of medullary phloem. In this and the following figures the xylem of the cotyledonary traces is shaded dark, x 300. Fig. 2. Do. lower down. Three internal phloem-groups are passing out. x 300. Fig. 3. Do. still lower. Another phloem-group is seen in the xylem on its way out. x 300. Fig. 4. Do. near root. Little medullary phloem is left. One group is seen passing out. x 300. Fig. 5. Transverse section of tap-root, showing typical diarch structure. All the phloem is now united in the normal position, x 300. Fig. 6. Asclepias obtusifolia. Part of a transverse section from a thickened root. Two phloem-islands shown imbedded in the xylem-parenchyma, near a group of Vessels, x 150. Figs. 7 and 8. Thladiantha dubia. Fig. 7. Semi-diagrammatic transverse section of a root to show the distribution of the tissues. The protoxylem-groups coloured red, the xylem generally yellow , the sieve-tubes blue , and the bast-fibres brown. Fig. 8. Part of a transverse section from a similar root, showing a secondary ray in which interxylary phloem has been formed, x 150. Figs. 9-12. Chironia peduncularis. Fig. 9. Part of a transverse section of an octarch root, moderately thickened, to show general structure, ph 2 is here the approximately central group of medul- lary phloem. Two protoxylem-elements are seen to the outside of the cambium. An intermediate one has become imbedded in the secondary wood, x 150. 300 Scott and Brebner . — On Internal Phloem , &c . Fig. 10. Part of a transverse section of a young octarch root at the commence- ment of secondary thickening. The cambium is forming inside the isolated proto- xylem-elements. Primary in terxylary phloem-groups are in course of development. X 300. Fig. 11. Do. do. from a decarch root, at a stage very slightly later than Fig. 10. Four protoxylem-groups shown. To the left the cambial divisions take place inside the protoxylem. The cambium passes outside the next two groups, and on the right divisions are seen on both sides of the protoxylem-element. This root had a considerable pith containing a large group of internal phloem, x 300. Fig. 12. Do. do. from a root at nearly the same stage as Fig. 9, showing the centrifugal development of the phloem-islands on the inner side of the cam- bium. x 300. Figs. 13 and 14. Apocynum cannabinum. Fig. 13. Part of a transverse section of a stem in which the normal wood is 70-90 cells thick. The development of centripetal wood from the internal cam- bium has just begun. It is separated from the protoxylem of one of the primary bundles by one or two layers of parenchyma, x 1 70. Fig. 14. Similar section from an older stem. The internal wood is now about 15 cells thick. The internal phloem projects far into the pith, x 170. Fig. 15. Willughbeiafirma. Part of a transverse section from a thick stem, showing the centripetal wood and internal cambium and phloem, and their relation to the protoxylem of the normal wood, x 300. Figs. 16-20. Acantholimon glumaceum. Fig. 16. Semi-diagrammatic transverse section of an old stem, to show the distribution of the tissues. Red — protoxylem. Yellow — xylem generally. Blue — phloem. The cortex, rays, and pith are left white. Fig. 17. Part of a transverse section showing the inner part of the normal wood, the centripetal wood, and the internal cambium and phloem. The centri- petal wood is alone shaded, x 300. Fig. 18. Longitudinal section of the same. Notice specially the loosely coiled spirals of the protoxylem-vessels, on the inner side of which the centripetal wood is forming. Some of the internal sieve-tubes have callous plates, x 300. Fig. 19. Transverse section showing part of an interxylary band of cambium and phloem. The cambium lies on the inner side of the phloem, x 300. The external zone of wood {oca) begins with large vessels. Fig. 20. Longitudinal section of the same. The callous plates of the older interxylary sieve-tubes are shown. The outer part of the inner zone of wood (x2) consists chiefly of narrow spirally thickened vessels, while the inner part of the outer zone {x2d) has large pitted vessels, x 300. All the figures were drawn under the camera lucida. Those x 300 were drawn with a power of 450 diam, and subsequently reduced to two-thirds. G.Bre'bner del. SCOTT & BREBNER.- ON INTERNAL PHLOEM. University Press, Oxford. G Bre'biier del. University Press, Oxford. SCOTT & BREBNER— ON INTERNAL PHLOEM. •V . . Jbvnals of Botany SCOTT & BREBNER.— ON INTERNAL PHLOEM. Vol KPls.IIX. ■JO 3 cbz i-phz University Press, Oxford. Jtnnals of Botany Vol V.PL.XIX. University Press , Oxford. G.BreVnei del. Hi ^JTarf Jjauds of Botany Vol. V;PL.XX. Fig. 19. iiUJ /,«V ' . ?M oV ^ — i-^^st;-. :■--■•■ 0 0 0 { ., /■'■ cV®®.©.0® n,T”. it f ■ *-<>' " Ki 0 „ ,n(] ®©u)©0 " ’■; ' _ a o « * °° G-.Brebner del University Press, Oxforl. SCOTT & BREBNER. - ON INTERNAL P H L 0 E M . A Summary of the new Ferns which have been discovered or described since 1874. BY J. G. BAKER, F.R.S. Keeper of the Herbarium , Royal Gardens , Kew. ( Continuation . ) Genus 38. Asplenium, Linn. Subgenus Euasplenium. 13*. A. Robinsoni, F. M., in Journ. Bot. 1884, 289. Norfolk Island, Robinson. I believe this to be identical with A. squa- mulatum , var. ? Smithii , Hook., a garden plant of unknown origin. 15*. A. Maetierii, Beddome, in Journ. Bot. 1888, 3. Malay Peninsula. 15*. A. Scortechinii, Beddome, in Journ. Bot. 1887, 322. Perak, Scortechini. 15*. A. holopbyllum, Baker, n. sp. Frond simple, lanceolate, subcoriaceous, glabrous, 3-4 in. long, ■§-§ in. broad at the middle, narrowed gradually to the apex and a very short stipe. Veins immersed, erecto-patent, simple or forked. Sori short, ceasing a space from the edge, not above ^ in. long. Indu- sium simple, broad, firm, glabrous, persistent. Formosa; Tamsui Mountains, Hancock , 101. 17*. A. melanolepis, Baker, in Journ. Bot. 1890, 264. Tonquin, Balansa , 1919. 20*. A. longissimum, Baker, in Journ. Bot. 1891, 4. North-West Madagascar, Last. 25*. A. fllieaule, Baker, in Journ. Bot. 1881, 204. New Granada; province of Antioquia, Kalbreyer. 25*. A. holophlebium, Baker, in Journ. Bot. 1877, 163. Andes of Ecuador, Sodiro. 26*. A. Delislei, Baker, n. sp. Tuft with long stolons rooting at the end. Basal paleae minute, lanceolate, clathrate, nearly Annals of Botany, Vol. V. No. XIX.. August 1891.] 302 Baker. — A Summary of the new Ferns black. Stipes 1-2 in. long, slender, green, naked. Frond linear-lanceolate, simply pinnate, green, glabrous, 3-4 in. long, \ in. broad. Pinnae rhomboid, sessile, truncate on the lower and inner side, crenate on the upper and outer ; lowest pinnae distant and dwarfed. Veins distinct, flabellate, 5-6 to a pinnae. Sori short, broad. Indusium glabrous, persistent. Bourbon, Delisle , 592. Near A. viride and Kraussii. 33. A. San&ersoni, Hook. Further material shows that A. Han- ningtoni, Baker, in Journ. Bot. 1883, 245, from the Usagura Mountains, is a form of this species, and that A. brachy- ptoron and Bregeanum, Kunze, are dareoid varieties. 34. A. dentatmn, L. I can only separate as a variety A. jamai- cense, Jenm. in Journ. Bot. 1886, 208, from the Mountains of Jamaica. 37. A. Triehomanes, L. # I cannot separate specifically the New Zealand A. xnelanolepis, Colenso, in Trans. New Zeal. Instit. 1888, 227, and the Portuguese A. Caput-serpentis, Plenriquez. 37*. A. Keuteri, Milde, Fil. Eur. 62. Cilicia, Balansa. Not seen. 42. A. normale, Don. Received lately from Japan, China, Siam, Sumatra, and Madagascar. 42*. A. leucostegioid.es, Baker, n. sp. Stipes very short, tufted, castaneous, with a few minute crisped linear-subulate paleae. Fronds lanceolate, membranous, simply pinnate, 2-3 in. long, f-i in. broad, with a few minute . paleae on both surfaces. Pinnae sessile, rhomboid-oblong, J in. broad, very oblique at the base. Veins few, distant, erecto-patent, lower forked. Sori oblong or orbicular, not more than 2-3 to a pinna. Indusium membranous, green, glabrous. East Maui, Sand- wich Isles, F. L. Clarke. Received from Mr. G. E. Daven- port. 44*. A. parviiium, Mart, et Gal. Stipes densely tufted, short, black, wiry. Fronds lanceolate, simply pinnate, 4-6 in. long, •J- f in. broad. Pinnae sessile, oblique oblong, auricled on the upper side at the base, cuneate-truncate on the lower side ; lower pinnae gradually smaller. Sori medial, oblong, 5-6-jugate in the central pinnae. Mexico and Southern United States. 48*. A. ludens, Baker, in Journ. Linn. Soc. XIX, 294. Solomon Isles, Rev. R. B. Comins . Near A. multilineatum , Hook. discovered or described since 1874. 303 50*. A. Poolii, Baker, in Journ. Linn. Soc. XV, 416. Central Ma- dagascar, Pool. 53. A. Vieillardii, Mett. New Caledonia. Very variable in cutting. I place as varieties A. sehizodon, Moore, in Gard. Chron. 1871, 1004; A. apieidens, Moore, in Gard. Chron. 1881, I, 267 ; and A. Baptistii, Moore, in Gard. Chron. 1881, I, 235. See also var. facile, Moore. 54*. A. Moorei, Baker, n. sp. Stipe long, green, naked. Fronds oblong-deltoid, simply pinnate, moderately firm, glabrous, a foot long and broad. Pinnae multijugate, lanceolate, dis- tinctly petioled, serrated, the lowest \ ft. long, an inch broad at the base, cuneate on the lower side. Veins distinct, forked, very ascending. Sori J-f in. long. Indusium narrow, firm, persistent, glabrous. Solomon Isles, Chas. Moore. Between A. Vieillardii and lucidum . 56*. A. pachysormn, Baker, in Journ. Bot. 1891, 4. North-West Madagascar, Last. Very near the West African A. longicauda, Hook., of which Kalbreyer has found a bipinnate variety. 64*. A. Hancoekii, Maxim. Mel. Biol. XI, 868. Formosa, Han- cock. Differs from A. lunulatum by vestiture, entire pinnae, and sori reaching from midrib to margin. 65*. A. Mannii, Hilleb. FI. Hawaii, 594. Sandwich Isles, Seemann , 2240, Hillebrand. Near A. per sicifolium^ J. Sm. 65*. A. Steerei, Harringt. in Journ. Linn. Soc. XVI, 28. Mount Mahayhay, Philippines, Steere. 70. A. eultrifolium, L. I cannot separate specifically A. puluia- huae, Sodiro, Recens. Crypt. Vase. Quit. 33, from the Andes of Ecuador. 77. A. contiguum, Kaulf, w&Y.jissum, Moore, in Gard. Chron. 1881, 267, is a subbipinnate variety, and Paralleloneuron Neitneri, Hort., a still more deeply cut form of this species. I have not seen A. Knudsenii and nitidulum, Hilleb. FI. Hawaii 601. 81*. A. Balfourii, Baker, n. sp. Stipes 6-9 in. long, clothed throughout with lanceolate, brown paleae, with a pale margin. Fronds oblong-lanceolate, simply pinnate, 2-3 ft. long, 8-9 in. broad, moderately firm, glabrous : rachis scaly throughout. Pinnae lanceolate, serrated especially towards the tip, 4-4 1 in. long, an inch broad, cuneate on the lower side at the base ; lower gradually smaller. Veins distant, erecto-patent, forked. 304 Baker . — A Summary of the new Ferns Sori reaching from the midrib nearly to the edge, J-J in. long. Bourbon, Balfour . Near A. compressum , Sw.. of St. Helena. 87*. A. Schweinfurthii, Baker, in Balf. Bot. Socot. 328, t. 100. Socotra, Schweinfurth. Balfour. 88. A. obtusatum, Forst. Under this, as defined in Synopsis Fili- cum, range the Sandwich Island A. Kaulfussii, Schlecht., Hilleb. FI. Hawaii, 592, and the New Zealand A. anomodum, Colenso, in Trans. New Zeal. Instit. 1882, 309. 88*. A. cesatianum, Baker, in Malesia, III, 39. New Guinea, on Mount Arfak, Beccari, 92*. A. sherburgense, Baker, n. sp. Stipes tufted, 3-4 in. long, clothed with deciduous subulate paleae. Fronds oblong-lanceo- late, simply pinnate, moderately firm, glabrous, a foot long, i|-2 in. broad, rooting at the tip. Pinnae 20-25-jugate, sessile, oblong, crenate, J-J in. long, f in. broad, cuneate on the lower side at the base, slightly auricled on the upper ; rachis thinly clothed with bristly paleae like those of A. crini - caule. Veins erecto-patent, simple except the lowest. Sori regular, simple, parallel, remote from the edge. Indusium glabrous, persistent. Sherburg Island, Upper Guinea, Mrs. Mair. Near A. crinicaule , Hance. 94. A. falcatum, Lam. I have not seen the Sandwich Island A. pseudo-falcatixm, Hilleb. FI. Hawaii, 597, nor the New Caledonian A. fastigiatum and dentato-serratum, Fourn. in Ann. Sc. Nat. s 6r. 5, XVIII, 305. 95. A. eaudatum, Forst. A. decipiens, Kuhn, in Reise Decken. Bot. 71, Johanna Island, Hillebrand , 1773, differs from the type by its more deeply cut pinnae and frond dwarfed gradually at the base. 100*. A. oligophlebium, Baker, in Gard. Chron. n. s. XIV, 494. Japan, Maries. Near A.formosum, Willd. 102. A. resectum, Smith. A. unilaterale , Lam. Ency. II, 305 (1786), is an older name for this species. 105*. A. centrifugale, Baker, in Journ. Linn. Soc. XXV, 360. Christmas Island, J. J. Lister . Very near the Indian A. planicaule , Wall. 105*. A. castaneo-viride, Baker, n. sp. Stipes tufted, castaneous below, green above, 2-3 in. long. Frond lanceolate, pinnate, discovered or described since 1874. 305 subrigid, green, glabrous, \ ft. long, i-i| in. broad at the middle, narrowed gradually to the base. Pinnae sessile, un- equal-sided, laciniate-pinnatifid. Veins indistinct, erecto- patent. Sori finally forming a continuous mass, covering the whole pinna, except the tip and outer edge. China ; Chefoo, Hancock , 14. 106*. A. formosanum, Baker; A. Hancockii , Baker, in Journ. Bot. 1885, 104, non Maxim. Formosa, Hancock , 134. Allied to A. laciniatum and the small forms of A. affine . 107*. A. subaquatile, Cesati, Fil. Born. Beccar. 20, tab. 3, fig. 5. Borneo, first gathered by Beccari, later by Curtis and Bishop Hose. 114*. A. Lydgatei, Hilleb. FI. Hawaii, 596. Sandwich Islands. “ Allied to A. diffiorme , R. Br.” Not seen. 119. A. pekinense, Hance. Further material shows that 132, A. Saulii, Hook., in Blakistone’s Yangtsze, 303 (1862), is a larger, more compound form of the same species, and the latter is the older name. It has lately been found by Levinge in the Himalayas (Chumba and Jhelum Valley). 124*. A. sphenotomum, Hilleb. FI. Hawaii, 529. Sandwich Islands. Not seen. 125. A. furcatum, Thunb. An earlier name for this cosmopolitan species is A. praemorsum , Swartz, Prodr. FI. Ind. Occ. 130 (1788). 126. A. affine, Swartz. In Madagascar this proves to be excessively variable in cutting. I now refer here A. simillimum, Kuhn, in Hildeb. Madag. Exsic. No. 3773; A. Gilpinae, Baker, in Journ. Linn. Soc. XVI, 200 ; A. herpetopteris, Baker, in Journ. Linn. Soc. XVI, 20 ; and A. viviparoides, Kuhn, in Hildeb. PI. Madag. Exsic. No. 4148. See also vars. Pecten and tanalense , Baker. 133. A. fontanum, Bernh. I place as a variety very near exiguum, A. yunnanense, Franchet, in Bull. Bot. Soc. France, XXXII, 28, gathered in Yunnan by Father Delavay. 133*. A. chihuahuense, Baker, n. sp. Stipes densely tufted, casta- neous, green upwards, J-i in. long. Frond oblong-deltoid, bipinnate, moderately firm, glabrous, an inch long. Lower pinnae the largest, sessile, ovate, lobed down to the base on the upper side (lobe obovate-cuneate), cuneate-truncate on the 306 Baker. — A Summary of the new Ferns lower side. Veins flabellate. Sori medial, linear or oblong. Indusium pale, persistent, glabrous. Mexico ; province of Chihuahua, Pringle , 144, in collection of 1887. Allied to A.fontanum. 134*. A. coenobiale, Hance, in Journ. Bot. 1874, 142 —A.fuscipes, Baker, in Journ. Bot. 1879, 3°4- Canton, Ford. 134*. A. moupinense, Franchet, PI. David. II, 152, Tibet; pro- vince of Moupine, David. Near A. varians and incisum. 144. A. bulbiferum, Forst. I cannot from the descriptions separate A. eanterburiense, Armstrong, in Trans. New Zeal. Instit. 1881, 361, New Zealand, and A. meiotomum, Hilleb. FI. Hawaii, 596, Sandwich Islands. Subgenus Darea. 156*. A. becearianum, Cesati, Prosp. 7. New Guinea, Beccari. Be- tween A. Mannii and obtusilobum. 165*. A. loxoscaphoid.es, Baker, in Trans. Linn. Soc. ser. 2, Bot. II, 354. Mount Kilimanjaro, alt. 8000 ft., Johnston, 43. 168*. A. sertularioides, Baker, in Trans. Linn. Soc. ser. 2, Bot. II, 354. Mount Kilimanjaro, alt. 9000-13,000 ft., Johnston , 26. 174*. A. Solmsii, Baker, in Hemsl. Biol. Cent. Amer. Bot. Ill, 639. Guatemala, Bernouilli and Cario, 317. Like the dareoid forms of bulbiferum . Subgenus Athyrium. 178. A. spinulosum, Baker. Has lately been found in Japan by Maries, and in Yunnan by Delavay. Further material shows the East Himalayan A. subtriangulare, Hook., cannot be separated as a species. 180*. A. Atkinsoni, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 487 = Athyrium Atkinsoni , Bedd. Ferns Brit. Ind. Suppl. 11, t. 359. Himalayas; and var. Andersom] Clarke, loc. cit. t. 57. 184*. A. mongolicum, Franch. PI. David. I, 351. China. Habit of A. thelypteroides , with indusium almost of a Lastrea. 184*. A. Henryi, Baker, n. sp. Stipes long, naked, tufted, strami- neous. Fronds oblong-lanceolate, bipinnate, moderately firm, glabrous, 1-2 ft. long. Pinnae sessile, lanceolate, the largest discovered or described since 1874. 307 6-8 in. long, in. broad, cut down nearly to the rachis into oblong crenate secondary lobes \ in. broad. Veins 9-10-jugate in secondary lobes ; veinlets forked. Sori medial, much curved. Indusium glabrous, persistent. West China ; Hupeh and Patung, Dr. A. Henry. Near A. thelypteroides. 185*. A. nephrodioid.es, Baker, in Journ. Bot. 1887, 170. West China ; Patung, Dr. A. Henry. Frond narrowed gradually from the middle to both ends. Indusium like that of a Lastrea. 189*. A. Kewtoni, Baker, n. sp. Stipes long, tufted, stramineous or castaneous, with a few lanceolate paleae. Fronds oblong- lanceolate or subdeltoid, 2-3-pinnate, moderately firm, glabrous, 1-1J ft. long, 8-12 in. broad. Many lower pinnae, subequal, oblong-lanceolate, 4-5 in. long, 1J-2 in. broad. Pinnules oblong-lanceolate ; tertiary segments deeply crenate, in. broad, with a cuneate base. Upper veins simple ; lower forked. Sori round, medial. Indusium much curved, glabrous. Island of St. Thomas, West Tropical Africa, Newton. Very near the Indian A. macrocarpum , Blume. 190. A. nigripes, Blume. Beddome places as a variety A. Clarkei, Atkinson ; Clarke, in Trans. Linn. Soc. ser. 2, I, 489. Eastern Himalayas. 192*. A. Duthiei, Beddome, in Journ. Bot. 1889, 72. Garwhal and Kumaon, Duthie. 193. A. oxyphyllum, Hook., var. kulhaitense , Atkins.; Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 494, is a form with the indusium obsolete. 194*. A. Baldwinii, Hilleb. FI. Llawaii, 618. Sandwich Isles. Near A. aspidioides. 197*. A. lastreoides, Baker, in Journ. Bot. 1888, 227. China, Mount Omei, alt. 3500 feet, Faber , 1064. 198*. A. umbrosum, J. Sm., var. cristovalense, Baker, in Journ. Linn. Soc. XIV, 294, is a very compound variety allied to assimile. Beddome places as a variety of australe the Himalayan A. helium , Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 496, plate 63, fig. 2. 199*. A. oosorum, Baker, in Journ. Bot. 1876, 343. Samoa, Whitmee. Near A. woodwardioides in sori, but frond much larger and more compound. 308 Baker . — A Summary of the new Ferns Subgenus Diplazium. 203*. A. porphyrorachis, Baker, in Journ. Bot. 1879, 4°- Borneo, Beccari , Burbidge. Polypodium subserratum, Hook. Syn. Fil. 325, gathered by Wallace, is this plant in an immature sterile condition. 205. A. pallidum, Blume. I cannot separate A. Prentieei, Bailey, in Trans. Linn. Soc., N. S. Wales, IV, 37. Queensland. 205*. A. chlorophyllum, Baker, in Journ. Bot. 1885, 104. For- mosa, Hancock , 97. 205*. A. Harrisoni, Baker, in Journ. Bot. 1884, 362. Costa Rica, Harrison. 205*. A. aequibasale, Baker, in Journ. Linn. Soc. XXII, 225. Sarawak, Borneo, Bishop Hose. 206*. A. macrotis, Baker, in Journ. Bot. 1884, 362. Costa Rica, Harrison. 208*. A. verapax, Donnell Smith, in Bot. Gaz. 1888, 77, t. 2. Guatemala. Very near A. Riedelianum , Bongard, of Brazil. 207*. A. xiphophyllum, Baker, in Journ. Bot. 1879, 40. Borneo, Burbidge. 209*. A. leptorachis, Baker, in Journ. Bot. 1890, 264. Tonquin, Balansa , 1833. Near A. Seemannii , Baker. 209*. A. Pullingeri, Baker, in Gard. Chron. 1874, 484. Hong- Kong, Pullinger . Cultivated at Kew. Near A. Seemannii. 210*. A. Campbelli, Jenman. Stipes tufted, naked, J ft. long. Frond simply pinnate, deltoid, moderately firm, glabrous, J ft. long and broad. Pinnae 3-5, lanceolate, 3-5 in. long, i-i^ in. broad at the middle, crenate, deltoid at the base, narrowed to the point. Veins ascending, forked. Sori J-J in. long. Indusium narrow, glabrous. British and Dutch Guiana, Jenman. Near A. bantamense , Baker. 210*. A. longisorum, Baker, in Journ. Bot. 1881, 204. Antioquia, Kalbreyer , 1876. Near A. bantamense. 216*. A. megaphyllum, Baker, in Journ. Bot. 1890, 264. Tonquin, Balansa , 1836. Near A. celtidifolium. 216*. A. mocennianum, Sodiro, Recens. Crypt. Vase. Prov. Quit. 37. Andes of Ecuador, Sodiro. Between A. celtidifolium and sylvaticum. 217*. A. Sammadii, Kuhn, Reise Decken. Bot. 34. Niam-Niam Land, Central Africa, Schweinfurth , 3117. Near A. syl- discovered or described since 1874. 309 v ait cum. Pinnae i|-2 in. broad, shallowly lobed. Lobes sharply toothed. Veins few in a group. 219*. A. sandwichense, Hilleb. FI. Hawaii, 610. Sandwich Islands. Near A. arbor eum. 220*. A. brevipes, Baker, in Journ. Linn. Soc. XVI, 201. Central Madagascar, Miss Helen Gilpin. Near A. Shepherdi. 221. A. semihastatum, Kunze. Has lately been found in Porto Rico by Sintenis. 221*. A. monticolum, Jenm. in Journ. Bot. 1882, 326. Jamaica, Sherring , Morris , 250. Near A. Mildei. 226*. A. fenzlianum, Luers., in Flora 1875, 434. Sandwich Isles, Wawra. Near A. sylvaticum and japonicum. 226*. A. xnarginale, Hilleb. Fil. Hawaii, 613. Sandwich Isles. Near A. fenzlianum. 229*. A. erenato-lobatum, Baker, n. sp. Stipe brownish, naked, J ft. long. Fronds lanceolate-deltoid, bipinnatifid, bright green, glabrous, i\ ft. long. Pinnae lanceolate, sessile, the largest | ft. long, j-i in. broad, cut down to a narrow wing into oblong obtuse conspicuously, crenate lobes £ in. broad. Veins pinnate in the secondary lobes : veinlets simple, distant, ascending. Sori medial, the lowest diplazioid. Indusium glabrous. Sandwich Islands. Cultivated at Kew in 1879. Near A. speciosum and sorzogonense. 233. A. sorzogonense, Presl. I place as a variety A. Stoliezkae, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 500 —Diplazium Stoliezkae , Beddome, Ferns Brit. Ind. Suppl. 13, t. 361. Himalayas. 233*. A. crinitum, Baker, in Journ. Linn. Soc. XXIV, 258 =A. sorzogonense , var. majus, Hook. Further material received from the Bishop of Singapore and Sarawak shows that this is a distinct species. 235*. A. laffanianum, Baker, in Gard. Chron. 1882, I, 73; Bot. Challenger, I, 84, t. 12. Bermuda. Near A. crenulatum. Cultivated at Kew in 1880. 235*. A. diminution, Jenman, in Journ. Bot. 1881, 53. Jamaica. Like A. Franconis on a small scale. 236*. A. Wheel eri, Baker, n. sp. Stipe long. Frond membranous, deltoid, nearly tripinnate, ij ft. long. Pinnae and pinnules lanceolate, the latter sessile, reaching i|-2 in. long, J-f in. 310 Baker . — A Summary of the new Ferns broad, cut away on the lower side at the base, cut down to a narrow wing into oblong tertiary segments g-J in. broad. Veins pinnate in the tertiary segments, the lowest veinlet forked, the rest simple. Sori oblong, medial, often diplazioid. Japan, Wheeler. Habit of A. deltoideum , Presl. 240*. A. earyaefolium, Baker, n. sp. Fronds ample, firm, bipin- nate ; rachises scaly. Lower pinnae oblong-lanceolate, above a foot long, 4-5 in. broad, with many free lanceolate nearly entire pinnules |-§ in. broad. Veins usually forked. Sori linear, touching the midrib, not reaching the edge. New Granada, Kalhreyer , 985. Near A. nervosum , Mett. 243*. A. Doderleinii, Luers., in Engler Jahrb. 1883, 355. Liu-kiu Archipelago, Japan, Doderlein. Near A. veslitum , Presl. 243*. A. polypodioides, Mett. I place as a variety A. sikki- mense. Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 500, tab. 65, fig. 1. Sikkim. 249. A. latifolium, D. Don. Beddome places under this variable species A. sueculentum, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 502, tab. 64, fig. 4, and A. torrentium, Clarke, loc. cit. p. 500, tab. 64, fig. 3 (excl. fig. 2, which is typical lati- folium). A . maximum , Don, appears to be merely a form of the same species. 249*. A. travancoricum, Beddome, Ferns, Brit. Ind. 188, under Diplazium. Travancore Hills. Very large, with pinnae 2 ft. long. 251. A. arboreseens, Mett. Much fresh material has been received. It has been sent from the Usagura Mountains by Sir John Kirk, and from the Island of St. Thomas, off the Guinea coast, by Professor Henriquez, and it now seems the Madagascar A. madagaseariense and A. nemorale, Baker, in Journ. Linn. Soc. XV, 417, had better not be separated specifi- cally. 253*. A. amplissimum, Baker, n. sp. Frond ample, tripinnatifid, moderately firm, bright green, glabrous ; rachises brown- stramineous, naked, or sparsely fibrillose. Pinnae oblong-lan- ceolate, 1 — 1 \ ft. long. Pinnules lanceolate, lower shortly petioled, 3-4 in. long, 1-1 J in. broad, cut down to a narrow wing into oblong-lanceolate crenate tertiary segments. Veinlets 6-7- jugate, mostly forked. Sori oblong, reaching from the midrib discovered or described since 1874. 31 1 half-way to the edge. Amboyna, Challenger expedition. Received from Professor Balfour. Near A . Arnotti , Baker, of the Sandwich Isles. 259. A. radieans, Schk. From this variable species I cannot clearly separate A. hartianum, Jenm. in Journ. Bot. 1886, 268, A. altissimum, Jenm. in Journ. Bot. 1879, 259, and A. taylorianum, Jenm. in Journ. Bot. 1886, 269, all three Jamaican. 261*. A. zanzibaricmn, Baker, n. sp. Frond ample, membranous, glabrous, deltoid, 4-pinnatifid. Pinnae oblong-lanceolate, 2 ft. long, 9-10 in. broad. Pinnules oblong-lanceolate, cut down to the rachis into lanceolate deeply pinnatifid tertiary segments with oblong erecto-patent lobes. Veins pinnate in lower quaternary segments. Sori sausage- shaped, not more than iVtV in- long, lower diplazioid. Indusium narrow, membranous. Zanzibar, Last. 261*. A, brunneo-virido, Jenm. in Journ. Bot. 1886, 269. Jamaica, Morris , 264, Shewing. Near A. sandwichianum. Mett. 261*. A. Huttoni, Baker, n. sp. Fronds ample, deltoid, decom- pound, moderately firm, glabrous. Pinnae oblong-lanceolate, a foot or more long. ' Pinnules lanceolate ; tertiary segments oblong, obtuse, | in. broad, deeply pinnatifid; quaternary lobes oblong, obtuse. Veins pinnate in the quaternary lobes ; veinlets ascending, simple. Sori medial, reach T\- in. long. Indusium firm, glabrous, persistent. Malay Isles, Hutton. Received from Messrs. Veitch. Near A. sandwichianum , Mett. Subgenus Anisogonium. 264*. A. Virchowii, Kuhn, in Hildeb. PI. Madag. Exsic. No. 4168. South Betsileo Land, Madagascar, Hildebrand. Frond simple, lanceolate. 264*. A. Corderoi, Sodiro, Recens. Crypt. Vase. Prov. Quit. 39. Andes of Ecuador, Sodiro. Frond lanceolate, simple or simply pinnate. Pinnae oblong. 266*. A. eardiopbyllum, Baker; Micropodium cardiophyllum, Hance, in Journ. Bot. 1883, 268. Rhizome slender, wide-creeping, naked. Stipe slender, naked, castaneous, 7-8 in. long, arti- z 312 Baker . — A Summary of the new Ferns ciliated at the base. Frond simple, cordate-ovate, mem- branous, 4-5 in. long ; basal lobes orbicular, an inch broad ; costa ebeneous. Veins immersed, anastomosing towards the margin of the frond. Sori ascending, medial, irregular, at most an inch long, all single. Hainan, Formosa, B. C . Henry. 2 68*. A. Forbesii, Baker, n. sp. Rootstock not seen. Stipe naked, 5-6 in. long. Frond deltoid, simply pinnate, a foot long, glabrous, moderately firm. Pinnae 3-jugate, lanceolate- acuminate, entire, sessile, ft. long, 2-2J in. broad, cordate at the base. Veins 3-5-jugate, anastomosing towards the margin of the frond. Sori linear. Java : Province of Bantam? H. 0. Forbes, 459. Near A. lineolatum , Mett. 271*. A. macrodietyon, Baker, in Journ. Bot. 1877, 193. Andes of Quito, Sodiro. 271*. A. hemionitideum, Baker, in Journ. Bot. 1877, 163. Andes of Ecuador, Sodiro. 273*. A. fuscum, Baker; A. fuliginosum , Sodiro, Recens. Crypt. Vase. Prov. Quit. 40, non Hook. Andes of Ecuador, Sodiro. 274*. A. esculentum, Presl. Further material shows that A. vitiense, Baker, is a form of this species, and I cannot from the description separate A. dietrieManum, Luerss. in Mus. Godef. V, 16. Queensland. 275*. A. platyphyllum, Baker, in Journ. Bot. 1890, 264. Ton- quin, Balansa , 1847. Genus 41. Scolopendrium, Smith . 1*. S. Delavayi, Franchet, in Bull. Soc. Bot. France, XXXII, 29 ; Clarke, in Journ. Linn. Soc. XXV, t. 41. Yunnan, Delavay. Manipur, Watt , Clarke. Frond small, orbicular; midrib none; veins free. 5*. S. Balansae, Baker, in Hook. Ic. t. 1653. Paraguay, Balansa , 2885. Genus 41*. Diplora, Baker. D. integrifolia, Baker, Solomon Isles, is figured Hook. Ic. t. 1651. discovered or described since 1874. 313 Genus 41*. Triphlebia, Baker . Differs from Scolopendrium and agrees with Diplora in having a prominent receptacle running down the centre of the sorus. Here it arises from a sort of adventitious vein, not always produced beyond the sorus, but in Diplora the receptacle runs along the proper vein, and the two valves of the indusium do not spring from veins. Four species are known, as follows : — 1. T. pinnata, Baker, in Malesia, III, 41 : Hook. Ic. t. 1652 = Scolopendrium pinnatum , J. Sm. Philippines, Cuming , 137, 31 1. 2. T. longifoBa, Baker, 1. c. = Scolopendrium longifolium , Presl. Rel. Haenk. I, 48, t. 9, fig. 1. Philippines, Haenke. Sarawak, Borneo, Dr. Hose. 3. T. Linza, Baker, in Malesia, III, 42, t. 5 — Asplenium Linza Cesati, Fil. Bee. Polyn. 4. New Guinea, Beccari . 4. T. dimorphophylla, Baker, in Malesia, III, 42, t. 4= Asplenium subserratum, Cesati, non Blume. Island of Andai, North of New Guinea, Beccari. Asplenium scolopendropsis, F. M. Notes, Papuan plants III, 49, gathered in New Guinea by D' Albertis, probably also belongs to Triphlebia and may be identical with T. Linza . Genus 43. Aspidium, Sw. Subgenus Polystichum. 3*. A. basipinnatum, Baker, in Journ. Bot. 1889, 176. China; Kwantung Province, Ford , 103. 5*. A. xiphophyllum, Baker, in Journ. Bot. 1888, 227. China; Mount Omei, alt. 5000 feet, Faber , 1040. Near A. munitum and falcinellum. 5*. A. auritum, Baker ; Phanerophlebia aurita , Fee. Fil. Bras. Suppl. 70, tab. 100, fig. 1. Rio Janeiro, Glaziou, 4431. 6*. A. Macleaii, Baker, in Hook. Ic. tab. 1654. Drakensbergen, Transvaal, Me Lea, Ayres. 9*. A. otophorum, Franchet, PI. David. II, 154. Moupine, Tibet, Father David. Between A. Lonchitis and auriculatum. 11*. A. Atkinsoni, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 506; Polystichum Atkinsoni, Beddome, Ferns Brit. Ind. tab. 362. Bhotan and Sikkim. 314 Baker. — A Summary of the new Ferns 12. A. Iriangulum, Sw. I place as a variety A. candatum, Jenm, in Journ. Bot. 1879, 260. Jamaica, Jenman. 13. A. anrieulatum, Sw., vars. submarginale and stenophyllum , Baker, in Journ. Bot. 1888, 227. China, Faber and Ford. 13*. A. deltodon, Baker, in Gard. Chron., n. s., XIV, 494. Ichang gorge, Central China, Maries. 13*. A. lanceolatum, Baker, in Gard. Chron., n. s., XIV, 494. China. This and the last are nearly allied to A. auricidatum. 14*. A. acanthophyllum, Franchet, in Bull. Soc. Bot. France, 1885, 28. Yunnan, Delavay. Nearly allied to A. ilicifolium. 14*. A. phaeostigma, Cesati, Fil. Becc. Polyn. 7. New Guinea, Beccari. Habit and texture of Nephrodium crassifolium , but indusium distinctly peltate. 1 8. A. aculeatum, Sw. I should now reduce as varieties of this species 21. A. obtusum, Mett., and 22. A. californicum, Eaton. 20. A. mohrioides, Bory. Has been found in California by Lemmon and Pringle, and in the Falkland and Auckland Isles, and also in the Antarctic Island of Amsterdam. 23. A. Richardi, Hook. A. oculatum, Hook, is evidently a mere variety. 26*. A. moupinense, Franchet, PL David. 153. Moupine, Tibet, Father David. Near A. prescottianum , Hook. 26*. A. bakerianum, Atkinson ; Baker, in Hook. Ic. tab. 1656. Himalayas. Placed by Beddome as a variety of A. pres- cottianum. 26*. A. capillipes, Baker, in Journ. Bot. 1888, 228. West China, Mount Omei, Faber , 1086. 29*. A. Haneoekii, Baker; A. reductum , Baker, in Journ. Bot. 1888, 105; Ptilopteris Haneoekii , Hance, in Journ. Bot. 1884, 139. Tamsui, Formosa, Hancock , 41. Very near A. tripteron , Kunze. 30. A. laserpitiifolium, Mett. I cannot separate A. festimim, Hance, in Journ. Bot. 1883, 269, found near Canton by Faber. This species has also been found in Tonquin by Balansa. 31. A. maximowiezianum, Miquel, Prolus. 343. Japan, Maxi- mowicZy Dickins. Intermediate between aculeatum and aris- ta turn. discovered or described since 1874. 315 35. A. ascendens, Sw. Here belongs Nephrodium duale, Donnell Smith, in Amer. Bot. Gaz. 1890, 29, tab. 4, gathered in Guate- mala by Baron von Turckheim. 37. A. aristatum, Sw. I place as a variety A. exile, Hance, in Journ. Bot. 1883, 268, gathered in Che-Kiang, by Stonach. 40. A. mnltifidnm, Mett. I cannot separate specifically Poly- stiehiim Pearcei, Philippi, in Linnaea, XXXIII, 805, gathered in Chili by Pearce. 41. A. sikkimense, Baker = Nephr odium sikkimense, Clarke, in Trans. Linn. Soc. ser. 2, Bot, I, 52. Distributed also as Lastrea della , Clarke. Like A . varium , this stands on the line between Aspidium and Nephr odium, which I should not in a new book keep up as genera. 42*. A. caruifolium, Baker, in Journ. Bot. 1888, 228. Mount Omei, China, alt. 3000-3500 ft., Faber , 1027. 42*. A. Wattii, Beddome, in Journ. Bot. 1888, 231. Manipur, Watt , 6715. Subgenus Cyrtomium. 46*. A. Boydiae, Eaton, in Bullet. Torrey Club, 1879, 359- Hawaii, Baldwin. Subgenus Euaspidium. 51*. A. Murrayi, Baker, n. sp. Stipe naked, stramineous. Fronds deltoid, membranous, glabrous, a foot long, with a shallowly pinnatifid oblong-cuneate end-segment and two pairs of sessile pinnae, the lowest produced on the lower side and deeply lobed towards the base. Main veins parallel, arcuate, \ in. apart, with copious hexagonal areolae between them, with free included veinlets. Sori small, copious, scattered irregularly. Indusium peltate, persistent, glabrous. St. Lucia, H. B. Murray. 52*. A. trilobum, Sodiro, Recens. Crypt. Vase. Prov. Quit. 41. Andes of Ecuador. 53*. A. becearianum, Baker, in Malesia, III, 43 ; A. calcareum , Cesati, Fil. Polyn. Becc. 4, non Presl. Island of Andai, olf the coast of New Guinea, Beccari. 53*. A. subrepandum, Baker, n. sp. A. repandum , Sodiro, Recens. 42, non Willd. Stipes tufted, naked, above a foot long. Fronds oblong-lanceolate, membranous, glabrous, simply pin- nate, above a foot long ; apex pinnatifid. Pinnae 3-4-jugate, 3 1 6 Baker —A Summary of the new Ferns lowest the largest, produced on the lower side, the others lanceolate acuminate, sessile, 6-8 in. long, an inch broad at the middle. Main veins fine, erecto-patent, under ^ in. apart, with copious hexagonal areolae between them. Sori in two rows near the main veins, 3-4 in a row. Indusium large, peltate, persistent. Andes of Ecuador, Sodiro. Genus 44. Nephrodium, Rich. Subgenus Lastrea. 4*. N. brachypodum, Baker, in Trans. Linn. Soc. ser. 2, Bot. II, 290. Roraima, im Thurn. 4*. N. longieaule, Baker, in Journ. Bot. 1881, 204 ; Hook. Ic. tab. 1658. Antioquia, New Granada, Kalbreyer , 1454. 6*. N. Dickinsii, Baker ; Aspidium Dickinsii , Franch. et Savat. Enum. Jap. II, 236, 639. Japan and China. 6*. N. Faberi, Baker, n. sp. Stipe stramineous, 6-8 in. long, clothed up to the top with ovate brown membranous paleae. Frond oblong-lanceolate, simply pinnate, moderately firm, \ ft. long, 3 in. broad, scattered over with scales beneath ; rachis paleaceous. Lower pinnae longest, lanceolate, sessile, in. broad, auricled on the upper side at the base, rounded on the lower side. Veins obscure. Sori principally in two rows near the midribs of the pinnae. Indusium small, evanescent. Ningpo, China, Faber , 205. Near N. decipiens and Dickinsii. 6*. N. parallelum, Baker, in Journ. Linn. Soc. XV, 417. Central Madagascar, Pool, Kitching. 7*. N. Sheareri, Baker, in Journ. Bot. 1875, 200; N. isolaium , Baker, in Gard. Chron., n. s., XIV, 494. Kiu-Kiang, China, Shearer , Maries ; Ningpo, Hancock. 8*. N. enneaphyllmn, Baker, n. sp. Stipe 8-9 in. long, densely scaly at the base ; paleae lanceolate, bright brown. Frond deltoid, simply pinnate, moderately firm, glabrous, 8-9 in. long and broad. Pinnae about 9, lanceolate, petioled, truncate at the base, crenate, the lowest the largest, 4 in. long, an inch broad. Veins in pinnate groups, free ; veinlets 3-4-jugate, ascending. Sori small, almost restricted to the central half of the pinnae. Ichang, China, Henry , 3217. Between N. po- dophyllum and Sieboldii. discovered or described since 1874. 317 10. H. hirtipes, Hook. Found in China by Hancock, and Samoa by Whitmee. Polypodium Seottii, Beddome, Ferns Brit. Ind. t. 345, appears to be a form without indusium. 10*. N. triehophlebium, Baker, in Journ. Linn. Soc. XVI, 201. Central Madagascar, Mrs. Pool . 10*. N. fibrillosum, Baker, in Journ. Linn. Soc. XV, 418. Central Madagascar, Pool, 15*. ET. semilunatum, Sodiro, Recens. Crypt. Vase. Prov. Quit. 46. Andes of Ecuador. Near N. insigne, Baker. 16. 1ST. gracileseens, Hook. Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 514, describes three Himalayan varieties, decipiens , hirsutipes , didymochlcenoides. I have not seen Aspidium laxurn, Franch. et Savat. Enum. Jap. II, 237. 16*. TL Humblotii, Baker, in Bull. Linn. Soc. Paris, 534. Comoro Isles, Humblot , 274. Allied to N. albo-punctatum and sub- biauritum. 16*. N. mongolicum, Baker. Aspidium mongolicum , Franchet, in David, Exsic. No. 2273. South Mongolia, Father David. 16*. N. ochrorachis, Baker, in Journ. Bot. 1854, 142. North-east Madagascar, Humblot , 272. 17*. FT. Eournieri, Baker. Aspidium flaccidum , Fourn. in Bull. Soc. Bot. France, 1880, 328. Mexico. 17*. FT. pubirachis, Baker, in Journ. Bot. 1876, 344. Samoa, Whitmee. 17*. N. Holmei, Baker, n. sp. Rootstock not seen. Stipe | ft. long, substramineous, glabrous, naked. Frond oblong-lanceo- late, bipinnatifid, membranous, a foot long, densely pilose on the rachis, and main ribs ; rachis not scaly. Pinnae lanceolate, sessile, the largest 3 in. long, f . in. broad, cut down nearly to the rachis into entire oblong segments |— §- in. broad ; lower pinnae reduced at the base. Veins very distinct, 8-9-jugate, simple. Sori few, medial. Indusium minute hispid, fugacious. Montserrat, Rev . H. R. Holme . 17*. N. borbonicum, Baker, n. sp. Rootstock not seen. Pinnae naked, 4-5 in. long, brown at the base, stramineous above it. Frond oblong-deltoid, bipinnate, \ ft. long, thick, with a few small bullate scales on the under surface. Pinnae lanceolate, sessile or shortly petioled, the lowest not reduced, iJ-2 in. long, f-f in. broad; segments entire, in. broad; lowest 3 1 8 Baker r — A Summary of the new Ferns sometimes slightly compound. Veinlets simple, erecto-patent, 8-io-jugate. Sori small, supramedial. Indusium minute, fugacious. Bourbon, D elide, 331. 17*. N. savaiense, Baker, n. sp. Rootstock rather creeping; pa- leae linear, brown. Stipe 6-9 in. long, naked, pilose. Frond oblong-lanceolate, bipinnatifid, subcoriaceous, 12-15 in. long, 8-9 in. broad, pilose on the rachis and under surface. Pinnae lanceolate, sessile, cut down to the rachis into oblong lobes ^ in. broad. Veinlets simple, 10-12-jugate. Sori basal, minute. Indusium fugacious, densely bristly. Samoa, Powell , 183. 19*. FT. tibetieum, Baker. Aspidium thibeticum , Franch. PL David. II, 156. Moupine, Tibet, Father David. Near N. patens. 19*. N. Turckheimii, Donnell Smith, in Bot. Gaz. 1887, 133, tab. 11. Guatemala, Baron von Turckheim , 714. 22*. N. paucijugum, Jenm. in Journ. Bot. 1886, 270. Jamaica, S herring. Near N. Sloanei. 26*. N. japonieum, Baker, n. sp. Stipe subcastaneous, |-ft. long. Frond lanceolate, deltoid, bipinnatifid, membranous, finely downy, 12-15 in, long, 9-10 in. broad; rachis castaneo- stramineous, downy, not scaly. Pinnae lanceolate, sessile, acuminate, the lowest the largest, 4-5 in. long, f in. broad, cut down to a narrow wing into obtuse subentire lobes i-i-J in. broad. Veinlets simple, 8-9-jugate. Sori supra-medial. Indusium large, membranous. Nagasaki, Japan, Capt. Blom - field . 28. N. albo-punctatum, Desv. Oldest name is Polypodium pec- ' tinatum , Forsk. 28*. "N . zambesiacum, Baker, n. sp. Stipe not seen complete. Frond large, bipinnate, slightly hairy. Lower pinnae lanceo- late, a foot long, 1 1 in. broad, cut down to the rachis into entire acute lanceolate segments in. broad. Veinlets simple, 14-15-jugate. Sori medial. Indusium fugacious, membranous, glabrous. Zambesi Highlands, Buchanan. 29*. N. lepidum, Baker. Lastrea lepida , Moore, in Gard. Chron., n. s. XXVI, 681. Polynesia, Hort . Henderson. Very near the Vitian N. Prenticei. 29*. N. Sangnellii, Herb. Moore. Stipe long, naked, with a few discovered or described since 1874. 319 brown basal paleae. Frond oblong-deltoid, moderately firm, hairy on the main ribs beneath, above a foot long, a foot broad ; rachis naked, stramineous. Pinnae lanceolate, 5-6 in. long, J-f- in. broad, cut down to a narrow wing into obtuse segments in. broad; lower pinnae rather reduced. Veinlets 8-9-jugate, simple. Sori medial. Indusium small, mem- branous. New Caledonia, Hort . Birkenhead. Near N. calca - ratum , Hook. 35*. "N . valdepilosum, Baker, in Journ. Bot. 1888, 204. New Granada, Antioquia, Kalbreyer , 1347, 1871. 33. N. erinitum, Desv., var. exaggeratum, Baker. Fronds deltoid, free lanceolate pinnules reach an inch long, obtusely lobed. Veins subpinnate in the lower lobes. Sori 2-4 to a lobe. Central Madagascar, Pool. Bears same relation to type that elongatum bears to Filix-mas. 36*. N. regulare, Baker, in Journ. Bot. 1875, 200. China, Province of Kiu-Kiang, Dr. Shearer. 40*. 1ST. Buckholzii, Baker; Aspidium Buckholzii , Kuhn, Reise Decken. Bot. 47. Cameroon Mountains, Buckholz. Habit of Poly podium cyatheaefolium. 40*. N, beecarianum, Cesati, Fil. Bee. Born. 23. Sarawak, Borneo, Beccari. 40*. N. Luersseni, Harringt. in Journ. Linn. Soc. XVI, 29. Buluku Island, Philippines, Steere. 41*. N. polytrichum, Baker, in Journ. Bot. 1891, 107. West Borneo, Sarawak, Dr. Hose. A fine large plant, near N, crassifolium and Leprieurei. 44. N. sanctum, Baker, Andes of Quito, Sodiro. Var. magnum , Jenm., in Journ. Bot. 1886, 290, connects the type with N. conterminum. 45*. N. Sewellii, Baker, in Journ. Linn. Soc. XV, 418. Central Madagascar, Pool. 45*. N. anateinophlebium, Baker, in Journ. Linn. Soc. XVI, 202. Central Madagascar, Miss Helen Gilpin. 47. 1ST. Beddomei, Baker. Lately found in the Philippines by Micholitz, in China by Dr. Henry, and in Moupine, Tibet, by Father David. 47*. N. perakense, Beddome, in Journ. Bot. 1888, 4. Perak, Day . Near N. Beddomei. 320 Baker.— A Summary of the new Ferns 48*. "No nevadense, Baker; Aspidium nevadense, Eaton, Ferns North Amer. 73, tab. 10. California, on the Sierra Nevada. 49. N. contermintim, Desv. Under this very variable species fall 3ST. brachypus, amphyoxypteris, lasiopteris, stenophyllum, and stramineum, Sodiro, Recens. Crypt. Vase. Prov. Quit, p. 43-51, from the Andes of Ecuador and the Jamaican N. earibaeum and noekianum, Jenm. in Journ. Bot. 18 86, 270. 49*. N. simulans, Baker, in Journ. Bot. 1890, 106. Mount Knuts- ford, New Guinea, Sir W. Macgregor. Very ne r N. con- fer minum. 49*. N. fasciculatum, Baker ; Aspidium fasciculaium, Fourn. in Ann. Sc. Nat. ser. 5, XVIII, 295. New Caledonia, Balansa , 1611, 3568. Not seen. 49*. N. Seemanni, Baker, n. sp. Rootstock not seen. Stipe short, naked. Frond oblong-lanceolate, bipinnatifid, 2-2 1 ft. long, 8-9 in. broad, moderately firm, slightly hairy ; rachis naked. Pinnae very numerous, sessile, lanceolate, acuminate, J in. broad, cut down nearly or quite to the rachis into entire segments, \ in. broad ; lower pinnae reduced. Veinlets, 5-6- jugate, simple, erecto-patent. Sori supra-medial. Indusium firm, glabrous, persistent. Oahu, Seemann. Very near N. confer minum. 49*. N. firmum, Baker ; Jenm. in Journ. Bot. 1879, 260. Jamaica, Jenman. 52. N". Sprengelii, Hook. N. Sherringii, Jenm. in Journ. Bot. 1879, 261, is, I think, a variety of this species. 52*. N. conforme, Sodiro, Recens. Crypt. Vase. Prov. Quit. 45. Andes of Ecuador, Sodiro, type and var. strigillosum. Near N. Sprengelii. 53*. N. polylepis, Baker ; Aspidium polylepis, Franch. et Savat. Enum. Jap. II, 236, 631. Japan, Savatier, Dickins. Allied to JV. conterminum and prolixum. Distinguished by its few veins and scaly rachis and lamina. 53*. N. longicuspe, Baker, in Journ. Linn. Soc. XVI, 202. Central Madagascar, Miss Helen Gilpin. Near N. prolixum. 55*. N. retrorsum, Sodiro, Recens. Crypt. Vase. Prov. Quit. 51. Andes of Ecuador, Sodiro. discovered or described since 1874. 321 55*. N. atomiferum, Sodiro, Recens. Crypt. Vase. Prov. Quit, 48. Andes of Ecuador, Sodiro. 55*. "N. Canadasii, Sodiro, Recens. Crypt. Vase. Prov. Quit. 48, Andes of Ecuador, Sodiro. 55*. N. macradenium, Sodiro, Recens. Crypt. Vase. Prov. Quit. 48, Andes of Ecuador, Sodiro. This and the three last are allied to N. resinofoetidum and Sprucei. 57*. N. subjunctum, Baker, n. sp. Rootstock decumbent. Stipe naked, 5-6 in. long. Frond membranous, oblong-lanceolate, bipinnate, 2J-3 ft. long, 8-12 in. broad at the middle, narrowed to the base, finely pilose beneath, principally on the midrib of the pinnae ; rachis pilose. Pinnae lanceolate, sessile, the largest 6-8 in. long, |-f in. broad, cut down nearly to the midrib into linear-oblong entire lobes yV- § in. broad. Veinlets simple, 8-10-jugate. Sori sub-marginal. Samoa, Powell , 248. Habit of N. sophoroides , but veins free. 62*. N. carazunense, Baker, in Journ. Bot. 1877, 163. Andes of Ecuador, Sodiro . 63*. N. Jenmani, Baker, in Journ. Bot. 1877, 263. Jamaica, alt. 4000-5000 ft., and found lately in St. Vincent, by Messrs. H. H. and G. W. Smith, whilst collecting for Mr. F. D. God- man. 66*. N. Wilsoni, Baker, n. sp. Rootstock not seen. Frond oblong- lanceolate, nearly bipinnate, ij ft. long, \ ft. broad, pubescent beneath ; rachis nearly black, finely pubescent. Pinnae lanceolate, sessile, 3 in. long, cut down nearly to the midrib, with entire or crenate segments J in. broad ; lower pinnae not reduced. Veins 8-9-jugate, often forked. Sori sub- marginal. Indusium large, reniform, persistent. Uganda, Tropical Africa, Rev. C. T. Wilson. Habit of least compound forms of Polypodium distans . 66*. FT. Maearthyi, Baker ; N. puberulum , Baker, in Journ. Bot. 1875, 201, non Syn. Fil. edit. 2, 495. Central China, Dr . Shearer , Mac ar thy. 68. N. apiciflorum, Hook., is now placed byBeddome as a variety of Filix-mas , with which it is connected by var. Nidus, Clarke : Hook, et Baker, Syn. Fil. edit. 2, 498. 70*. N. imifureatum, Baker, in Journ. Bot. 1888, 228. Mount Omei, China, alt. 3500 ft., Faber, 1051. 322 Baker —A Summary of the new Ferns 70*. N. singalanense, Baker, in Journ. Bot. 1880, 212. Mount Singalan, Sumatra, alt. 5000-6000 ft., Beccari ’ 471. 71*. N. Dayi, Beddome, in Journ. Bot. 1887, 323. Perak, Scortechini , Day . 73*. N. ehontalense, Baker, Aspidium chontalense , Fourn. in Bull. Soc. Bot. Paris, XIX, 254. Chontales, Levy, 516. Not seen. 73. N. Filix-mas, Rich. FT. cochleatum, D. Don, which is kept up as a species by Clarke in Trans. Linn. Soc. ser. 2, Bot. I, 521, is placed again under Filix-mas by Beddome. I cannot separate specifically the Chinese Aspidium oxyodon, Franch. PL David. I, 353, the Hawaian A. hawaiense, Hilleb. FI. Hawaii, p. 575, and now think N. antarcticum, Baker, in Journ. Linn. Soc. XIV, 479, from Amsterdam Island, had better be placed here. 73*. N. Mannii, Hope, in Journ. Bot. 1890, 145. Assam, Mann. Allied to the compound forms of N. Filix-mas , but rachis densely paleaceous. 73*. N. subtriangulare, Hope, in Journ. Bot. 1890, 327. Assam, Mann. Not seen. 77. N. laeerum, Baker. Chefoo, Hancock. Both lacerum and erythrosorum are, in a broad sense, only varieties of Filix- mas. 78. ~N. erythrosorum, Hook. Aspidium prolificum, Maxim., which has been introduced into cultivation, is a monstrous form of this species. 83*. N. fragile, Baker; Polyp odium fragile, Baker, in Journ. Linn. Soc. XVI, 203. Central Madagascar, Miss Helen Gilpin. Further material shows that this has a reniform indusium. 83*. ~N. assamense, Hope, in Journ. Bot. 1890, 326. Assam, Mann. Habit of Asplenium ( Athyriurri ) nigripes. Not seen. 89. FT. fragrans, Rich., has been found by Maries in Japan. 91*. FT. eoriaceum, Hope, in Journ. Bot. 1890, 328. Assam, Mann. Texture and cutting of a small form of Pteris aquilina. Not seen. 92*. N. bissetianum, Baker, in Journ. Bot. 1877, 366. Japan, Bisset. Cutting of N. spinidosum. Remarkable for its copious peculiar paleae. 93*. N. xanthotriehium, Sodiro, Recens. Crypt. Vase. Prov. Quit. 52. Andes of Ecuador, Sodiro. discovered or described since 1874. 323 93*. N. tricholepis, Baker, in Hemsl. Biol. Cent. Amer. Bot. Ill, 651. Guatemala. 94. N. sparsum, Don. I cannot separate specifically Aspidinm pellucidum, Franchet, PI. David. II, 157. Moupine, Tibet, David. 101. N. Faleoneri, Hook. Further material shows this is a more compound variety of N. barbigerum. 103*. N. Layardi, Baker, n. sp. Caudex erect. Stipes densely tufted, naked, a foot long. Frond deltoid, tripinnate, a foot long, membranous, glabrous ; rachis naked. Lower pinnae the largest, deltoid, unequal-sided, all cuneate-truncate on the lower side at the base. Largest pinnules oblong, sessile, obtuse, crenate, in. broad. Upper veinlets of tertiary segments simple ; lower forked. Sori small, medial. In- dusium minute. Polynesia, probably Fiji, Layard. Near N. hirtum and chinense. 105. N. chinense, Baker; Aspidinm Forbesii, Hance, in Journ Bot. 1875, 198, cannot be separated. 105*. N. gymnophyllum, Baker, in Journ. Bot. 1887, 170. Nanto, China, Dr. Henry. Between N. chinense and sparsum . 117. N. odoratum, Baker^iV crenatum , Baker, FI. Maurit. 497, its oldest name being Poly podium crenatum , Forsk. 117*. FT. Fordii, Baker, in Journ. Bot. 1889, 177. Kwantung, China, Ford, 104. Very near N. crenatum. 118*. FT. Hendersoni, Baker, n. sp. Stipe pubescent, 4-5 in. long. Frond deltoid, tripinnate, 5-6 in. long, very hairy, especially on the rachis and midrib of the pinnae beneath. Lowest pinnae the largest, much produced on the lower side, the rest lanceolate and simply pinnate, their pinnules oblong-rhomboid, obtuse, J in. broad, the lower inciso-crenate. Veinlets distant, distinct, erecto-patent. Sori small, medial. Indusium minute, fugacious. Fernando Po, Henderson. Near pubescens and the small forms of subquinquefidum. 123. N. decomposition, R. Br. Kirk wishes to separate as a species the New Zealand N. pentangnlarum, Colenso, which has a creeping rhizome. It is figured and described under the name of decomposiium by Field, Ferns New Zeal. 1 3 1, tab. 5, fig. 7. 126. N. dissectum, Desv. Clarke separates as a species in Trans. 324 Baker . — A Summary of the new Ferns Linn. Soc. ser. 2, Bot. I, 526, tab. 73, N. ingens of Atkin- son, which Beddome still regards as a variety of dissectum. 128. N. splendens, Hook. West China, Dr. Henry. 131. N. scabrosnm, Baker. A plant gathered by Mann, in Assam, is close to this, but evidently distinct specifically. 131*. FT. Lastii, Baker. Rootstock and stipe not seen. Frond ample, deltoid, decompound, glabrous; rachis naked, stra- mineous. Lower pinnae oblong-lanceolate, a foot long ; pinnules lanceolate; tertiary segments oblong, obtuse, in. broad, cut down to the rachis into contiguous oblong quaternary lobes, toothed on the outer edge. Veins pinnate in the quaternary lobes. Sori costular. Indusium firm, glabrous, persistent. Namuli Mukua Country, South-east Tropical Africa, J. T. Last. Near N. scabrosum. 131*. N. sarawakense, Baker, in Journ. Linn. Soc. XXII, 225. Sarawak, Borneo, Bishop Hose. 131*. N. aciculatum, Baker, in Journ. Linn. Soc. XXII, 226. Sarawak, Borneo, Bishop Hose. 131*. N. speetabile, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 526, non Hook ,—Lastrea Hendersoni , Bedd. Ferns Brit. Ind. t. 377. Khasia and Nepaul. 134*. N. intermedium, Baker. I cannot separate specifically N. rhodolepis. Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 526. Himalayas. 134*. N. leueostipes, Baker, in Journ. Bot. 1885, 105. Formosa, Hancock. 137*. N. oligophlebium, Baker, n. sp. Stipe slender, naked, stramineous. Frond lanceolate-deltoid, tripinnatifid, ij- ft. long, membranous, glabrous. Several lower pinnae opposite, subequal, oblong-lanceolate, 4-5 in. long; pinnules sessile, lanceolate, the lower cut down to a narrow wing into conti- guous lobes ^2 in. broad. Veins pinnate in the ultimate segments, with simple distant 3-jugate veinlets. Sori sub- marginal, very small. Indusium glabrous, fugacious. Kiangsu, China, Quekett. Near N. setigerum. 138*. N. obovatum, Baker, in Journ. Bot. 1890, 265. Tonquin, Balansa, 1815. 139*. N. multisetosum, Baker, in Journ. Linn. Soc. XXII, 226. Sara- wak, Borneo, Bishop Hose. Habit of Polypodium ornatum , Wall. discovered or described since 1874. 325 141*. N. megaphyllum, Baker, in Journ. Linn. Soc. XXII, 227. Sarawak, Borneo, Bishop Hose. 142*. 1ST. myriolepis, Baker, in Journ. Bot. 1888, 34. St. Do- mingo, Baron Eggers , 1575. Near N. amplum. 145*. 1ST. setulosum, Baker, in Journ. Bot. 1890, 265. Tonquin, Balansa, 1856. Habit of N. villosum. 146. N. arborescens, Baker. I had much correspondence with the late Rev. T. Powell about this plant, and finally he came to the conclusion that he had made a mistake in reporting it as arborescent. I propose therefore to drop the name and keep up two nearly-allied Samoan species, as follows. 146*. N. Powellii, Baker, n. sp. Caudex erect. Stipes tufted, densely clothed with linear paleae, of which the lower are ij in. long. Frond deltoid, decompound, firm, glabrous, 2J-3 ft. long. Lower pinnae the largest, deltoid, a foot long. Pin- nules oblong-lanceolate; tertiary segments lanceolate, deeply pinnatifid, cuneate-truncate on the lower side at the base; lobes obtuse. Veins pinnate in the quaternary lobes ; vein- lets simple, erecto-patent. Sori medial. Indusium firm, glabrous, persistent. Samoa, Powell , 245. 146*. FT. ludens, Baker, n. sp. Rootstock decumbent. Stipes 1-2 ft. long : basal paleae linear, the lowest i-if in. long. Fronds oblong-deltoid, decompound, moderately firm, glabrous, 4-4 \ ft. long. Pinnae deltoid ; quaternary segments oblong, cre- nate. Veins pinnate in the quaternary lobes. Sori medial. Indusium firm, glabrous, persistent. Samoa, Powell , 87, 167. 146*. N. maximum, Baker, in Journ. Bot. 1884, 162. Fiji, Sir J. B. Thurston. 151*. N. ochropteroides, Baker, n. sp. Stipe stramineous, a foot long, furnished towards the base with copious spreading lanceolate brown paleae. Frond deltoid, subcoriaceous, gla- brous, tripinnate, a foot long. Pinnae cut away on the lower side at the base ; lowest the largest, deltoid, unequal-sided ; final segments ovate or lanceolate, contiguous, acute, at most J in. long. Veins pinnate ; veinlets obscure, erecto-patent. Sori medial. Indusium firm, reniform, persistent. Fox's gap, Jamaica, Hart. 153*. N. magnum, Baker, in Hook. leones, tab. 1663. North- east Madagascar, Humhlot , 265, 326 Baker . — A Summary of the new Ferns 153*. N. granulosum, Baker, in Journ. Bot. 1891, 4. North-west Madagascar, Last. Near N. efifusum. Subgenus Eunephrodium. 154*. N. Bakeri, Harrington, in Journ. Linn. Soc. XVI, 29 ; Hook, leones, tab. 1664. Panay, Philippines, Steer e. 157*. N. subintegrum, Sodiro, Recens. Crypt. Vase. Prov. Quit. 54 ; Poly podium subintegrum , Baker, in Journ. Bot., n. s., VI, 164. Andes of Ecuador, Sodiro. 158*. 3ST. Harrisoni, Baker; N. stenophyllum , Baker, in Journ. Bot. 1884, 363, non Sodiro. Costa Rica, Harrison . Near N. incisum and Skinneri. 159*. N. debile, Baker, in Journ. Bot. 1880, 212. Mount Singalan, Sumatra, Beccari , 433. Habit of Poly podium reptans , Sw. 161*. N. calcar eum, Jenm. in Journ. Bot. 1886, 271, and N. usita- turn, Jenman, Jamaica, Sherring and Jenman , are, I think, indusiate forms of Polypodium tetragonum , Sw. 161*. TL hastatmn, Jenman, in Journ. Bot. 1879, 261, Jamaica, Jenman , is, I believe, an indusiate form of Polypodium oblite - ratum , Sw. 162*. N. unitum, R. Br. I cannot distinguish specifically the New Zealand N. inaequilaterum, Colenso, in Trans. New Zeal. Instit. 1888, 229. 163*. N. lucidum, Baker, in Gard. Chron. 1887, II, 456. Central Madagascar, Pool. Cultivated at Kew, Oct. 1877. 165*. N. Hopei, Baker = N. microsorum , Clarke; Beddome, Ferns Brit. Ind. 270, non Hook. Sikkim. 165*. N. Wakefieldii, Baker, n. sp. Rootstock and stipe not seen. Frond oblong-lanceolate, bipinnate, 3-4 ft. long, ij ft. broad, moderately firm, pubescent on the ribs beneath ; rachis naked. Pinnae lanceolate, 8-9 in. long, f in. broad, cut down to a narrow wing, with linear-oblong lobes ^ in. broad ; lowest pinnae not dwarfed. Veins 9-10, simple, only the lowest joined. Sori near the margin. Indusium firm, persistent. Mombasa, Rev. T. Wakefield. Near N. extensum. 168*. N. aneitense, Baker. Aspidium aneitense , Fourn. in Ann. Sc. Nat. s6*. 5, XVIII, 297. Aneiteum and New Caledonia. Not seen. 169. ~N. procurrens, Baker. Doubtfully distinct from IV. molle. discovered or described since 1874. 32 7 1G9*. ~N. rampans, Baker, in Journ. Bot. 1889, 177. Hupeh, China, Dr. A. Henry , 7814. 176*. H Peripae, Sodiro, Recens. Crypt. Vase. Prov. Quit. 54. Andes of Ecuador, Sodiro. 176*. ~N. eminens. Baker, in Journ. Bot. 1880, 213. Mount Singalan, Sumatra, alt. 5000-6000 ft., Beccari , 455. 179*. philippinense, Baker. N. candicnlaium, J. Smith, non Sieber. Rootstock and complete stipe not seen. Frond oblong-lanceolate, bipinnatifid, 2-3 ft. long, 1-1J ft. broad, moderately firm, glabrous ; rachis naked. Pinnae lanceolate- acuminate, 8-9 in. long, J in. broad, cut down less than half way to the rachis into oblong erecto-patent lobes in. broad ; lower pinnae not dwarfed. Veins simple, 8-9-jugate. Sori medial. Indusium firm, glabrous, persistent. Philippines, Cuming , 10, 84, 338. Near N. arbuscula , but lower pinnae not gradually dwarfed. 179*. N. tenebricum, Jenman, in Journ. Bot. 1882, 326. Jamaica. Nearly allied to N. arbuscula. 182*. H. siniulans, Baker, in Journ. Bot. 1888, 325. Borneo, Bishop Hose , 231. Near N. latipinna, Hook. 183*. H. eurostotrichnm, Baker, in Journ. Bot. 1880, 329. Tanala, Madagascar, Kite king. Near N. pennigerum. 183*. ~N. costulare, Baker, in Journ. Linn. Soc. XVI, 203. Central Madagascar, Miss Helen Gilpin. 185*. 1ST. jamaicense, Baker, in Journ. Bot. 1877, 264. Jamaica, Jenman. 185*. H. bermudianum, Baker, in Voyage Challenger, Bot. I, 86, tab. 13. Bermuda. Cultivated at Kew in 1879 from plants sent by Sir R. Laffan. 186*. "N. deeadens, Baker, in Journ. Bot. 1884, 183. Viti Levu, alt. 2000 ft., Sir J. Thurston. 187*. N. Sintenesii, Baker — Aspiditim Sintenesii, Kuhn, in Sintenis, PI. Poitorico Exsic. No. 2136. Porto Rico, Sintenis. Near N. molle. 187*. N. devolvens, Baker, in Journ. Bot. 1885, 217. Rio Janeiro, Glaziou , 15,766. Midway between N. molle and refr actum. 194*. N. Rodigasianum, E. Morren, in Linden 111. Hort. n. ser. t. 442. Samoa. Differs from AT. truncatum by having the frond narrowed gradually to the base. Cultivated at Kew, 1883. A a 328 Baker .—A Summary of the new Ferns 194*. If. sakayense, Zeiller, in Bull. Bot. Soc. France, XXXII, 74. Perak, Morgan. Near N. truncation. Subgenus Pleocnemia. 197*. If. mierochlamys, Baker, in Journ. Linn. Soc. XV, 107. Little Kei Island, Polynesia, Moseley (Challenger Expedi- tion). 199*. If. fnscipes, Clarke, in Trans. Linn. Soc. ser. 2. Bot. I, 536, tab. 75= Pleocnemia membranifolia , Bedd. Ferns Brit. Ind. 225, t. 1 1 5. Tropical Asia. Habit of N. dissectum, but venation pleocnemioid. 199*. FT. oligodictyon, Baker, n. sp. Rootstock and stipe not seen. Frond oblong-deltoid, bipinnatifid, moderately firm, glabrous ; rachis without scales. Lower pinnae largest, equilateral, 9-10 in. long, 2 in. broad, cut down, to a broad wing into entire linear-oblong segments J in. broad. Veins copiously pinnate in the secondary lobes, forming areolae only in the wing. Sori medial, 10-12-jugate in the lobes. Indusium membranous, fugacious. Malay Isles, Hutton , in Plerb. Veitch. Near N. giganteum. 199*. If. Fournieri, Baker. Aspidium Vieillardii, Fourn. in Ann. Sc. Nat. ser. 5, XVIII, 299. New Caledonia, Vieillard, 1602. Near N. giganteum. Not seen. 200*. If. ehrysotrichum, Baker, n. sp. Frond ample, decompound, moderately firm, furnished on the rachises and ribs beneath with short bright yellow hairs. Lower pinnae oblong-lanceo- late, 1-1J ft. long, 6-8 in. broad; pinnules lanceolate, sessile, |-| in. broad, cut down to a broad wing into pinnatifid tertiary segments with oblong lobes. Upper veins forked, lower forming an arch. Sori small, one in each final lobe. Indusium persistent, glabrous. Samoa, Whitmee. 200*. H. artinexum, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 536. Pleocnemia Clarkei, Beddome, Ferns Brit. Ind. Suppl. 15, tab. 368. Khasia, Clarke. Subgenus Sagenia. 201*. If. pleiopodum, Baker, in Journ. Bot. 1888, 325. West Borneo, Bishop Hose , 232. Near N. singaporianum. Stipe winged. discovered or described since 1874. 329 202*. TL nebulosum, Baker, in, Journ. Bot. 1880, 213. Sumatra, Beccari , 575. 202*. N. domingense, Baker, n. sp. Stipes tufted, castaneous and slightly scaly towards the base, green and naked upwards. Basal paleae small, lanceolate, dark brown. Frond deltoid, glabrous, 6-9 in. long, imperfectly or perfectly tripartite. Pinnae oblong-lanceolate, slightly lobed on the lower side at the base ; end segment deltoid-cuneate. Main veins distinct nearly to edge; intermediate areolae copious, with free included veinlets. Sori small, scattered irregularly, sometimes confluent. Indusium small, glabrous. St. Domingo, Imray. Cultivated at Kew, 1881. Allied to N ternatum. 203*. N. quinquefidum, Baker, in Journ. Bot. 1890, 265. Tonquin, Balansa , 1948. 203*. N. subpedatum, Harringt. in Journ. Linn. Soc. XVI, 30. Formosa, Steer e. 205*. N. an tioqmanmn, Baker, in Journ. Bot. 1881, 205. Antioquia, New Granada, alt. 3000-4000 ft., Kalbreyer , 1806. Near N. subiriphyllum. 205*. N. snbconfluens, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 536 ; Aspidium subconfluens , Bedd. Ferns Brit. Ind. t. 364. Khasia. 207*. N. subdigitatum, Baker, in Journ. Linn. Soc. XXIV, 259. West Borneo, Bishop Hose , 196. Allied to N. Eobbii and sub- bipinnatum . 211*. N. Sodiroi, Baker, in Journ. Bot. 1877, 164. Andes of Ecuador, Sodiro. Near N. polymorphum. 212*. 35T. stenopteron, Baker, in Journ. Bot. 1890, 265. Tonquin, Balansa , 1857. 212*. TL Sherringiae, Jenman, in Journ. Bot. 1887, 99. Trinidad, S herring. Habit of N. macrophyllum, but sori numerous and scattered. 2 1 3*. IT. Endresi, Baker, n. sp. Stipe long, slender, naked, castaneous. Frond oblong-lanceolate entire, glabrous, cordate at the base, 6-8 in. long, 1 J-2 in. broad, the fertile smaller than the sterile. Main veins erecto-patent, parallel, distinct nearly to the edge, •J— J- in. apart, with copious areolae between them with free included veinlets. Sori in rows near the main veins. In- dusium glabrous, subpersistent. Costa Rica, Endres (Herb. Veitch). A a 2 330 Baker. — A Summary of the new Ferns 213*. I. hederaefolium, Baker, in Journ. Linn. Soc. XIX, 295; Hook., leones, tab. 1665. Solomon Isles, Rev. R. B. Comins. Near RT. Pica. 213*. FT. tripartitum, Baker, in Journ. Bot. 1879, 296; Hook, leones, tab. 1 666. Fiji, Horne , 562. Near N. Pica. 213*. FT. lawrenceanum, Baker; Sagenia lawrenceana , Moore, in Gard. Chron. 1881, I, 8. Mountains of Madagascar, alt. 3000 feet. Humblot. Like N. Pica on a very large scale. Named in compliment to Sir Trevor Lawrence, M.P., President of the Royal Horticultural Society. 216*. FT. Keekii, Baker; Aspidiian Keckii , Luerss. in Bot. Cen- trablatt, 1882, 76. Near N. latifolium , Baker. Sumatra, Keck. 217*. FT. maerosorum, Baker, in Journ. Linn. Soc. XIX, 295. Solomon Isles, Rev. R. B. Comins. Near N. decurrens. 217*. FT. Gardneri, Baker, n. sp. Stipes castaneous. Fronds oblong-lanceolate, simply pinnate, moderately firm, glabrous, i-ij ft. long. Pinnae including the lowest, very decurrent on the main rachis. Pinnae 2-jugate below the pinnatifid apex ; lowest the largest, oblong-lanceolate, 8-9 in. long, 2-2 \ in. broad at the middle. Main veins very arcuate, parallel, distinct nearly to the edge, J-J in. apart. Sori mainly in rows nearly the main veins. Indusium glabrous, subpersistent. Brazil, Organ Mountains, Gardner , 5947. Gongo Soco, Gardner , 5315. Very near N. decurrens. 217*. FI. mamillosum, Baker; Sagenia mamillosa, Moore, in 111. Hort., ser. 4, VI, t. 598. Malay Isles, Introduced into cultivation about 1886. Near N. decurrens. 218*. FT. Wightii, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 538, tab. 76; N. siifolium , Baker, Syn. Fil. 299, ex parte. Court- allum, Wight. 219*. FL juglandifolium, Baker, in Journ. Bot. 1879, 296. Samoa, Horne. Near N. Barteri and pachyphyllum. 219*. FT. Hosei, Baker; N. stenophyllum , Baker, in Journ. Linn. Soc. XXII, 227, tab. 11, non Journ. Bot, 1884, 363. Sarawak, Bishop Hose. 219*. FT. nudum, Baker, in Journ. Bot. 1879, 41. Lawas River, Borneo, Burhidge. 219*. FT. grande, Baker; Aspidium grande , J. Sm.; Hook. Sp. Fil. discovered or described since 1874. 331 IV, 55. Philippines, Cuming, 356. Appears to be specifi- cally distinct from N. pachyphyllum . 219*. N. amblyotis, Baker, n. sp. Sagenia amblyotis , Moore, herb. Stipe long, naked, castaneous. Frond oblong-lanceolate, simply pinnate, moderately firm, glabrous, a foot long, \ ft. broad ; rachis naked, castaneous. Pinnae 4-jugate below the pinnalifid apex, lanceolate, 4-5 in. long, f-i in. broad at the middle, the lowest with a large oblong lobe on the lower side at the base. Main veins faint, with copious intermediate areolae. Sori in two rows near the main veins. Indusium firm, glabrous. Polynesia, Hort. Veitch , 1879. Near N. pachyphyllum. 219*. FT. Lazarzaburii, Sodiro, Recens. Crypt. Vase. Prov. Quit* 55. Andes of Ecuador, Sodiro. Near N. pachyphyl- lum. 221*. N. athyrioid.es, Baker, in Journ. Bot. 1884, 363. Costa Rica, Harrison. Habit of Aspidium trifoliatum. 221*. FT. melanorachis, Baker, in Journ. Bot. 1888, 325. Sarawak, Borneo, Bishop Hose. 221*. N. multieaudatum, Clarke, in Trans. Linn. Soc. ser. 2, Bot. I, 540, tab. 77 ; Aspidium multieaudatum, Wall. Base of Khasia Hills and Chappedong. 221*. FT. kanakorum, Baker; Bathmium kanakorum, Yomn. in Ann. Sc. Nat., sdr. 4, XVIII, 301. New Caledonia, Balansa, 823. Not seen. 224*. IT andinum, Baker, n. sp. Stipe naked, stramineous. Frond oblong-deltoid, simply pinnate, membranous, glabrous, 1 J ft. long; rachis naked, stramineous. Pinnae 4-jugate, oblong- lanceolate, 8-9 in. long, the side ones 2-3 in. broad at the middle, the end one broader. Veins arcuate, parallel, -J-J in. apart. Sori in regular rows near the main veins. Indusium firm, glabrous. Eastern Andes, Pearce, 307. Genus 45. NEPHROLEPIS Schott. 1*. FT. cordifolia, Presl. I cannot separate specifically the New Zealand "N . flexuosa, Colenso, in Trans. New Zeal. Instit. 1888, 231. N. Duffii, Moore, in Gard. Chron. 1878, tab. 1 13, from North Australia, is apparently a monstrous form of this species, and N, Plum a, Moore, in 332 Baker —A Summary of the new Ferns , &c . Gard. Chron. 1878, I, 588, fig. 68, from Madagascar, a marked variety. 2*. IN. exaltata, Schott. Clarke and Beddome both agree that IN. volufoilis, J. Sm., should be kept up as a distinct species. I cannot separate specifically the Andine IN. intermedia, Sodiro, Recens. Crypt. Vase. Prov. Quit. 57. 3. IN. acuta, Presl. I cannot draw any definite line between this and N. exaltata. IN'. Bausei, Hort. Veitch, is a fine garden form, with deeply pinnatifid pinnae. IN. rufeseens tripin- natifida, Hort. Veitch; Gard. Chron. 1887, I, figs. 90, 91, is another handsome garden form. {To be continued .) Notes on the F ertilisation of South African and Madagascar Flowering Plants. BY G. F. SCOTT ELLIOT, M.A., B.Sc., F.L.S. With Plates XXI, XXII, and XXIII. rFHE following are the somewhat scattered and miscel- -1 laneous notes which I was able to make during a two years’ botanical trip. I found it quite impossible whilst travelling to make as thorough and complete observations as are really required to properly understand all the adapta- tions of a flower to insect-visitors ; but as most of the forms have not hitherto been studied in their native haunts, the following may be of some interest. I endeavoured to collect every insect which I saw visiting the flowers, and brought home with me a numbered collection. I have to thank M. Henri de Saussure for his extreme kindness in naming for me all my Hymenoptera from Madagascar (about 60 species), many of which were new to science. Mr. L. Peringuey, Assistant Curator of the South African Museum, Cape Town, gave me also about 76 names most of which were specific as well as generic. These were chiefly Coleoptera from South Africa, and my thanks are due to him for his very valuable assistance with these difficult forms. I have also to thank Mr. Waterhouse, of the British Museum (Natural History), for about ten of the commonest generic names ; I have not, how- ever, been able to obtain any other assistance at home from the magnificent collection of South African and Madagascar insects in that institution, and many of my insects are there- fore still unnamed. [Annals of Botany, Vol. V. No. XIX. August 1891.] 334 Scott Elliot . — On the Fertilisation of South The literature of this part of botany is so well recorded in Muller’s c Fertilisation of Plants,’ edited by D’Arcy Thompson (London, 1883), and in the further list given by Professor Macleod in the ‘ Botanisch Jaarboek,’ Tweede Jaargang, 1890, Gent (Vuylsteke), that I have in the text simply quoted their numbers for the different papers consulted. I have ventured to do this as these two books should certainly be in the hands of any one who is studying this branch of botany ; both are so full and complete that their assistance is invaluable. Anemone eapensis, L. Visited abundantly by the hive bee c.p., and also by numerous small Dipfera. — Cape Town. Cariea Papaya, L. (Figs. 1, 2.) The flowers have been described by Muller (Macleod, No. 421). They are remarkable for the extraordinary difference between the male and female. In the male there is a long thin corolla tube with the anthers arranged round the entrance, while an abundance of honey is secreted by the rudimentary ovary. The female flower, on the other hand, has perfectly free petals, and is much larger and of quite a different shape (see Fig. 1). I saw a sugar bird ( Nectarinia souimangd) carefully suck- ing the male flowers. These are also scented at night and are then much frequented by a hawk-moth (No. 464), which I thought also visited the female flowers. — Fort Dauphin. Byrnphaea stellata, Willd. The bright blue flowers are busily visited by bees. While the stamens are dehiscing, no pollen can be shed upon the stigma as the younger stamens are bent forward over them ; afterwards, however, as the anthers ripen, they turn outwards exposing the stigmata. Mr. Watson has already pointed this out for Nymphaea (Macleod, No. 581). The opinion of Schultz that self-fertilisation is unavoidable and the only method (Macleod, No. 51 6 a) is therefore without any foundation particularly as Williams has shown that in the closely related Victoria regia only 60 seeds were produced African and Madagascar Flowering Plants. 335 by self-fertilisation, while 300 were formed by cross-fertilisa- tion. (Muller, No. 775, also see Macleod, No. 244.) — Near Uitenhage. Viola decumbens, L . (Fig. 3.) The stigma is simple in this species and bends down- wards so as almost to touch the concave lower lip. On entering an insect will probably carry the extremity inwards and so shake the circle of stamens. The stigma is thus even more primitive than that of Viola tricolor (cf. Macleod, No. 337). — Houwhoek, Cape Colony, Polygala bracteolata, L. (Figs. 4-6.) The one-sided development of this flower is far more marked than in P. myrtifolia. Looking at the petals from above (Fig. 5), one sees that the whole carina is bent laterally to the left, while the alighting brush v is only developed on the right side : both the style and the lip of the carina are slightly bent over to the right so that the style emerges in a direction pointing towards the body of an insect which would be standing on the alighting brush. The upper petals are almost entirely free from the three lower (which form the carina), and the right has a rounded projection, or peg, which overlaps the left (/, Fig. 5). The style ends in a peculiar hammershaped head, the upper part b being the pollen-cup, while the stigma is on the inferior inner concavity st. So far as I could see, the pollen is originally shed into the hollow or bay h below the stigma, but when the flower is ready for insect-visits, almost all of it is found on the cup or upper part b. The pollen appears to be forced round into this cup by the growth of the style-extremity over to the right, and this also produces a twisting of the tip of the carina in the same direction. When a bee alights on the brush, the carina yields at the hinge x, and the insect’s right side is touched by the stigma and also receives the pollen. Small insects are kept out by the overlapping of the upper petals and the hairs developed at the hinge hv and upper edges of the carina hr Self-fertilisa- 356 Scott Elliot,— On the Fertilisation of South tion is not entirely excluded, for some of the pollen remains in h (compare Schulz, Macleod No. 516 a). In the great excentricity, only approached by P. myrtifolia (Muller, Nos. 178 and 360), and in the greater relative length and depth of the carina, this species departs widely from those hitherto described ( P . Chamaebuxus , comosa, myrtifolia , vulgaris , alpestris , etc. Muller, p. 122, Nos. 609, 352, 360; Macleod, Nos. 217, 516 a). — Near Cape Town. Polygala myrtifolia, L. The flowers are not so excentric, but otherwise similar to those of the preceding species. The stamens dehisce early and the pollen is heaped up on the upper hollow part of the style which is turned very slightly to the right side. When an insect alights upon the brush, the style catches on the edges of the carinal pouch, and is carried back a little way ; then, being set free, it springs back elastically and the pollen is jerked out with some force. Even in the resting position it has a slight tension, and when carefully removed from the carina springs upwards. Visitors : — Xylocopa violacea , ab. — Near Capetown. Muraltia Heist eria, DC. (Figs. 7, 8.) The genus Muraltia carries even further the curious similarity of Polygalaceae to Leguminosae pointed out by Delpino (Muller, No. 178), for in this genus there is an explosive mechanism quite as well marked as in Genista. The rigid sepals overlap one another and are ciliate at the margin to prevent the entrance of unnecessary insects. The superior lateral petals have extremely thick rigid claws (cl, see Figs.), and lie in close contact with one another above the carina. The latter is formed of the anterior and the two inferior lateral petals which are united to form a tubular sheath enclosing the staminal cylinder and style. Their ends, however, are free and form a broad attractive surface about one-third of an inch in diameter. The upper margins of the tubular petal-sheath above mentioned are extremely thick, and form ledge-like protuberances on its inner side. African and Madagascar Flowering Plants. 337 and (as will be seen from the figure of a transverse section of the flower in this part) these ledges are held together over the style by the rigid claws of the uppermost petals and the sepals. Now the carina has a distinct tension leading it to spring downwards while the style (and in a less degree the staminal sheath) have a very strong tendency to fly upwards. Hence, when the carinal ledges are made to slip over the style by an insect forcing its way under the claws of the upper petals, an explosion takes place, and the style springs up to a right angle with its former position while the carinal sheath turns down : an insect must then be struck by the inner vertical stigmatic part of the style, si, and also be touched on the abdomen by the pollen from the seven anthers which emerges in a globular mass. Honey seems to be secreted by four finger- like projections from the top of the ovary or possibly by the bases of the sepals. Visitors : — Hymenoptera : a large bee Xylocopa violacea ? Apis mellifica sucking (from exploded flowers chiefly). Diptera : Syrphus capensis. Coleoptera : Anisonyx ursus . — Cape Town. Muraltia serpylloides, DC. (Fig. 9.) In this species there is the same union of the three lower petals to form a carina enclosing the stamens and style, but the upper edges of this sheath are held together over the style by a deep depression on its upper surface which is fitted by a basal projection of the upper petals, thus forming an even closer similarity to Leguminosae than the preceding species. There is the same explosive emergence. Muraltia diffusa, Burch . Similar to M. Heisteria , but in this species the ovary is hairy in its exposed upper portion between the superior petals. M. phylicoides, Thunb . Also similar to M. Heisteria . Mundtia spinosa, DC. The three lower petals are united as in Muraltia, but on 338 Scott Elliot . — On the Fertilisation of South depression the style and stamens emerge without any explo- sion ; the petals return to their original position by elasticity. Visitors : — Apis mellifica very abundant and effecting fertilisa- tion, also Diptera. — Muizenberg. Sida earpinifolia, DC. The styles are at first erect and well above the anthers, so that cross-fertilisation is probable; subsequently they curve downwards so that in the final state they way touch the pollen and effect self-fertilisation. Honey appears to be secreted by the thickened bases of the petals and staminal sheath. The carpels separate into two short, sharp, diverg- ing horns, adapted to catch in the fur or feathers of animals and so disperse the seeds. Visitors : — Apis mellifica , ab. — Fort Dauphin. Hibiscus Trionum, L. Visitors : — Apis mellifica and two kinds of Diptera, all sucking (see Macleod, No. 337). Abutilon albidum, L. (Fig. 10.) The corolla tube is narrower at the throat than lower down, so that the distance between the anthers (when de- hiscing) and the nearest petal is usually about one or two lines ; in older flowers the stigmas take up a position exactly the same distance from the petals. Honey is secreted by the cupular base of the sepals, and fills the cavity below the petals and inside the calyx tube ; entrance to it is obtained by oval apertures between the claws of the petals. Visitors : — Apis mellifica abundant, usually crawling down the corolla and so effecting cross-fertilisation, but sometimes crawling over the mass of stamens in which it may effect either cross or self- fertilisation (cf. Fritz Muller on Abutilon , ‘ Embira branca,’ Muller, No. 557). Dombeya dregeana, Sond. The five staminodes are curved outwards, and form a sort of arcade between themselves and the petals, round which an insect must crawl to obtain the honey secreted by the petaline African and Madagascar Flowering Plants. 339 claws ; whilst doing so it must be covered with pollen from the extrorse stamens. Visitors: — Hymenoptera : Apis mellifica , ab., also a small bee. — King William’s Town. Pelargonium Eekloni, Haw. The white or flesh-coloured flowers of this species are very conspicuous, as they are placed on a leafless peduncle nearly two feet high ! There are seven stamens gradually increasing in length from above downwards ; the lateral and inferior stamens are also twisted in such a way that their anthers dehisce upwards, forming a flat pollen-covered surface which must be touched by the abdomen of an insect visiting the flowers. The stamens are protandrous, and when the anthers have fallen off, the five stigmas ripen and spread out in a starlike manner, the three upper style-branches being more curved back than the two lower, so that the stigmata occupy exactly the place formerly taken by the dehiscing anthers. The honey-canal is if inch long. Visitors : — Probably night- flying moths. I found one Hymenopterous insect (No. 334) stealing honey by biting a hole above the canal. — Pretoria. Pelargonium betulinum, Ait. Agrees generally with above species, but the filaments of the five upper stamens are connate for one to two lines. Honey canal about f of an inch long. Pelargonium hirtum, Jacq. Similar to preceding species, but with a honey-canal fully fifteen lines long. (On Pelargonium cf. Muller No. 198, which I have not seen.) Oxalis. All the species which I gathered at the Cape were tri- morphic, and displayed a very peculiar difference in the relative number of the different forms. For instance, in Oxalis variabilis , Lindl., I found twenty-three long-styled, twenty- seven intermediate, and fifty short-styled forms as the usual proportion in one locality. In Oxalis versicolor , L., on the other hand, the long-styled forms were the most common, the 340 Scott Elliot. — On the Fertilisation of South proportion being forty, twenty-nine, and thirty. Probably a sufficiently large series would make these differences vanish, at least in part. Impatiens capens©, Thunb . The flowers are protandrous, and the inclination of the spur is such that an insect must touch the anthers while its proboscis is in the spur (see Muller, p. 160). — Perie bush. Adenandra obtusata, Sond. This agrees in most respects with A. fragrans , R. & Sch., thoroughly described by Urban (Macleod, No. 557). It is markedly protandrous, and in young flowers the style is bent down amongst the peculiar stalked glandules which cover the ovary. The stamens are at first bent inwards, but as they mature they successively rise so that they dehisce between the staminodes. Each anther bears a little glandular stalked knob, which is at first directed inwards, but becomes reflex during dehiscence (probably this secretes a substance which makes the insect’s proboscis sticky, as Urban suggests). The staminodes are longer than the stamens, and their inner surfaces are covered with white hairs ; they are at first bent in, but subsequently become erect. The style eventually rises and becomes upright in the centre of the flower. I found numerous small Diptera and Coleoptera in the flowers. Agathosma elegans, Cham . Abundantly visited by large Diptera, which, wandering through the umbellate flowers, become dusted with pollen. The flowers are protandrous, and the stamens ripen succes- sively just as in A. glabrata, Bart & Wendl., thoroughly described by Urban (Macleod, No. 557). Diosma ericoides, L . As described by T release (Macleod, No. 546) this seems to have exactly the same arrangement as Agathosma. Quivisia grandifolia, Scott Elliot , Ined. (Fig. 84.) In this genus the petals are united at the tip in the bud, and so enclose the tubular sheath formed by the united staminal African and Madagascar Flowering Plants. 341 filaments and style. As the flower ripens, however, the staminal sheath and style elongate more than the petals, and (forcing their way between two petals) become greatly curved while still held by the tip of the petals ; eventually they become quite straight by the separation of the latter. The staminal tube, in its final state, is two and a half inches long, while the petals are only one and three quarters of an inch in length. Cross-fertilisation is rendered probable by the globular stigma (which almost blocks the entrance to the staminal tube), being above the polliniferous part of the anthers. Still self-fertilisation is not wholly excluded, as in older flowers the staminal sheath falls downwards over the bent style, and may thus bring its anthers in contact with the stigma. Honey seems to be secreted by hairs which cover the ovary. The peculiar elongation of the staminal sheath and the barren tips of the anthers, are curiously like Pro- teaceae. Cyclopia genistoides, Vent. (Figs. 11-16.) This flower belongs to the piston-type. The vexillum is very large, and its thick dome-shaped claw fits closely down over the honey entrance ; it is, moreover, the sides of the broad part of the vexillum which hold the two alae together above the carina. There is also a vertical plait in the alae which fits on to a triangular peglike projection of the carina {af. pc. ) ; both alae and carina are in their anterior part bent upwards, almost at a right angle to the axis of the flower ; their horizon- tal part rests on the lowest calyx-segment, which is expanded and lengthened to support them. The style lies close to the outer edge of the carina in a well-defined tubular sheath ; the pollen is pushed forward by the anthers of the short-anthered stamens (whose filaments do not seem to be thickened). The stigma emerges before the anthers, and is protected to a certain extent from its own pollen by a small ring of hairs. I thought, however, that the stigma had the same peculiarity as that of Anthyllis (cf. Muller, ‘Fertilisation of Plants/ p. 172). 342 Scott Elliot . — On the Fertilisation of South Po&alyria serieea, R. Br. (Figs. 17-20.) The vexillum is, as is usual in the genus, excessively large, and so broad that the basal lobes of the wing reach to the lower edges of the carina. The alae have an almost vertical claw, and are very broad ; they are bent under the carina below, and as at the same time they are held together by the vexillum above it, and also overlap one another laterally in front, the union is as close as possible, and the alae and carina must move together. The honey entrance is covered by the vexillum-claw ; the bases of the two highest lateral stamens are, moreover, expanded in a triangular manner, and their insertion is overlapped by that of the vexillum, so that entrance to the honey is rendered very difficult, and is only possible for large insects. Podalyria calyptrata, Willd. (Figs. 21-24.) This species has a similar though more specialised mechanism. The claws of the alae are entirely vertical. The upper margins of the alae are held together by the grooved midrib of the vexillum, while the lower margins pass below the carina. On depression, bending takes place at the junc- tion of alar limb and claw (which is horizontal). The stamens and style lie along the outer border of the carina in a sort of tubular cavity, and the younger anthers push up the pollen of both whorls as in Cyclopia. A gentle depression causes a thin ribbon of pollen to emerge, but a violent one produces emerg- ence of the style and anthers. Although the filaments are free they are rigid and expanded, and also possess hairy interstices, so that they are equivalent functionally to a sheath. The bases of the two superior lateral filaments are united a little way with the vexillum-claw. Visitors : — Xylocopa caffra , very ab., Apis mellifica , and another Hyme- nopterous insect, all efficient. Podalyria eaneseens, E. Mey . (Fig. 26.) Very similar to P. calyptrata , but the superior backward margins of the alar limb are brought back behind and below African and Madagascar Flowering Plants . 343 the basal lobes of the vexillum, and also thickened so that the union of the two is still more close. Podalyria euneifolia, Vent. (Fig. 25.) Similar to the other species, but with the edges of the carina in front folded one within the other so as to form a more perfect tubular cavity for the style and pollen. This species (as probably all the others) is visited abundantly by Xylocopa caffra, which is very common near Cape Town. Liparia sphaerica; L. (Figs. 27-30.) This flower is the most modified of any of the South African Leguminosae . The lowest calyx segment is very large (13 lines long and 7 lines broad) ; the four lateral calyx teeth are tucked under the revolute edges of the standard (see Fig. 27). The vexillum also is very rigid and has a strong arched claw. The alae are rather narrow with their superior surface spread out horizontally, while at their ends they are rolled together round the tip of the carina through half a turn, so as to form a conical bag, out of which the tip of the carina protrudes. An insect standing on the vexillum can effect cross-fertilisation just as well or possibly better than when entering by the carina ; firsts because the vexillum being rigid and supported by the upper calyx- segmenls cannot yield to its weight, and, secondly , because the carina and alae, being supported by the lowest expanded calyx-segment, cannot give bodily but simply allow the tip of the carina to slip a little further through the alae ; the carina, being thus squeezed by the latter, will at first allow the pollen to emerge as a thin thread, and finally permit the stigma to appear. I devoted many afternoons to the discovery of the insect which fertilises this rare flower, but I was unable to find it. Xylocopa could, however, do this. Priestley a villosa, Thunb. The basal lobes of the vexillum come wrell down over the sides of the flower. The alae and carina are connected by, first , a shallow depression of the former fitting on to a similar B b 344 Scott Elliot . — On the Fertilisation of South groove in the latter, and, secondly , by the auricles of alae and carina which fit over one another behind. (The carinal edges are also swollen where they meet above the staminal sheath.) On depression the stamens and style emerge and cannot return within the carina. — Cape Town. Amphithalea ericaefolia, E. & Z. (Figs. 31-34.) The sides of the vexillum are revolute and the lateral sepals are tucked in behind them, as in Liparia , while the anterior sepal steadies and supports the carina. There is a large triangular peg on each side of the carina which fits into a deep socket-like groove of the alae ; the margins of the alae above this socket are thickened, while their lower margins turn inwards below those of the carina. Hence the alae and carina are quite inseparable. On depression the stamens and style emerge. The hairs on the ovary keep off small insects. Borbonia cordata, Z. (Figs. 35-37*) This flower is perhaps nearest in all essential points to Lotus (cf. Muller, p. 167). There are, however, some very marked differences in which it approaches very closely to some of the Aspalathi. The vexillum, e. g., has a long and arched claw, and the basal lobes of the limb are so turned down that they press upon the superior surfaces of the alae. The latter have rather deep longitudinal grooves corresponding to these points of depression (i.e. of the vexillum), and their lower surfaces are also bent inwards along their whole length and to such an extent that, at the junction of the alar claw and limb, the surfaces of the alae are entirely horizontal, and are in contact below the carina. The latter has a marked lateral bulging on either side, with a groove above and below, and this is closely embraced by the alae on both sides. Hence, on depression, alae and carina move together (the alae bending at the horizontal surface near the junction of limb and claw). The five outer anthers push up the pollen as in Lotus , and the odd stamen grows with them (sometimes showing an inter- mediate form of anther). The stigma and then the pollen (as a conical mass round the style) emerge on depression. The A frican and Madagascar Flowering Plants . 345 alae have a slight tendency to spring upwards when loosened from the carina, and this must tend to bring the carina back to its original position after depression. Rafnia angulata, Thunb . The outer whorl of stamens with the odd filament push up the pollen as in Borbonia , but the connection of alae and carina is much looser than in that genus. The upper edges of the alae are held together by the median groove of the vexillum and the upper edges of the carina form a flat trian- gular surface, fully 2 lines broad in front of the vexillum. The alae, however, embrace the carina below, as in Borbonia . Lotononis involucrata, Bth. (Figs. 42-46.) The effect of the elongated inferior calyx-tooth, character- istic of the genus, is to strengthen the carina which rests on it. The alae and carina are connected in three ways : first , by a deep groove in the carina, fitted by a depression of the alae ; secondly , by the overlapping of the superior backward pro- jections or auricles of both alae and carina; and, thirdly, by the inferior backward projections of the alar wings which are in contact below the carina. The alae are kept in contact with the carina by the downward prolongation of the vexillum- wings, which are almost as deep as the carina itself; they also overlap vertically in front On depression the alae are sepa- rated from one another, as well as bent down, and the carina opens very widely to allow the style and stamens to emerge. Lotononis prostrata, Bth. (Figs. 38-41.) Very similar to preceding species. Viborgia obeordata, Thunb. The structure is almost identical with the last species. Aspalathus aemula, E. Mey (Figs. 47-50). The vexillum has a long arched claw, and its two basal lobes fit into a deep groove on the superior surface of the alae, as in Borbonia : the lower edges of the alae are also slightly bent inwards below the carina at junction of the limb and claw. The carinal halves have a rather deep longitudinal B b 2 346 Scott Elliot . — On the Fertilisation of South depression along their upper surfaces, into which the alar depression fits. The style and stamens emerge by a rather oblique slit at the end of the carina. Aspalathus sareantha, Vog. (Fig. 55.) The basal lobe of the vexillum on each side fits into a deep superior hollow of the ala, which again works on a lateral projection of the carina. The lower edges of the alar claw (just before the limb) are turned inwards, and touch one another below the carina. On depression the alae rotate on this horizontal portion, which is just inside the calyx. The stigma and anthers emerge as in A. aemula. The alae have a marked tendency to curl upwards, so that when set free from the carina their tips come in contact with the vexillum ; this tendency will assist in bringing back the carina to its original position after depression. Aspalathus Chenopoda, Thnnb . (Figs. 51-54.) This form shows a further advance in structure, as the claws both of alae and carina are firmly adherent to the sta - minal tube , and bending is entirely confined to the junction of alar limb and claw. The inner edges of the vexillar basal lobes are extremely hairy, and their lower extremities fit into the hollow between alar limb and claw, so keeping out all useless insects and also keeping in the honey which is very abundantly secreted. Moreover, at first the pollen merely emerges as a ribbon-like mass (just as in Lotus), though after repeated depressions the stigma and anthers also emerge just as in A. aemula. Visitors: — Hymenoptera : (No. 192, an undescribed species). Diptera : a Bombylid, Pangonia angu - lata. Crotalaria eapensis, Jacq . (Fig. 56-60.) The flowers are of the same general type as those of Lupinus , but are marked by the extraordinary depth of the carina as seen from the side. The upper surfaces of the carina, moreover, are bulged out horizontally, and the alae having the same shape, embrace it very closely (Fig. 60) : their vertical superior margins are held together by the deep African and Madagascar Flowering Plants. 347 groove in the vexillum. The stamens are differentiated into two distinct whorls, of which those with the shorter anthers push up the pollen as in the Lupine. The style is protected from its own pollen by hairs on its inner surface. On depres- sion a thin streak of pollen exudes from the drawn out conical end of the carina, and subsequently the stigma appears. The honey is protected by the thick, flat, and rigid vexillum-claw which fits over the entrance. Visitors : — Xylocopa cajfra and Apis mellifica , both ab. Crotalaria retusa, L. (Figs. 61, 62.) Very similar to the preceding, but with the vexillum- claw even more specialised to cover the honey entrance. I also found that in the buds the vexillum completely covers the carina, the sides being wrapped together in front, and in consequence of this the style, which is at first directed obliquely upward from the end of the ovary, is unable to develop, and therefore takes the peculiar downward curve (see Figs. 58, 64), and which is characteristic of the genus. After the vexillum has been freed from the carina, no further elongation of the style takes place. Visitors : — Hymenoptera : (probably Xylocopa violacea ), Allodape Elliotii , De Sauss., standing on vexillum and sucking head downwards. Diptera : Philanthes diadema. Lepidoptera : two spp. sucking (Nos. 630, 634). — Fort Dauphin. Crotalaria humilis, E. Z. (Figs. 63-65.) In this species the tip of the carina and enclosed style are spirally twisted together, a further specialisation rendering the piston-action more complete. In other respects it agrees with C. capensis. Visitors : — Apis mellifica , ab. Psoralea deeumbens, Ait. The flower has an explosive mechanism : the staminal sheath having a distinct tendency to fly upwards, though the alae and carina have very little, if any, downward tension. Equilibrium is maintained by the vexillum which holds the alae together above the carina. The alae and carina are also united by, firsts a groove in the alae lying upon a slight 348 Scott Eltiot .• — On the Fertilisation of South bulging of the carina, and, secondly, by the swollen basal auricles of the alae which project backwards covering similar though smaller lobes of the carina. An insect raising the vexillum causes explosion. (Cf. Sprengel, loc. cit. p. 363 on P. bituminosa.) Visitors : — Apis mellifica , very ab.—Cape Town, Oct. Psoralea pinnata, L . Visitors : — Hymenoptera : Large bee (? Xylocopa), Apis mellifica , etc. Lepidoptera : spp. — East London. Indigofera filiformis, Thunb . That the carina of this genus has an elastic tendency to spring downwards was pointed out so long ago as 1837 by Don, ‘ General History of Dichlamydeous Plants.’ The flowers of Indigofera macrostachya , Vent, have been excellently described by Delpino (No. 178, Muller); those of /. speciosa by Henslow (No. 323, Muller), and those of /. Dosua by Meehan (No. 385, Macleod). In this species I found exactly the same general structure. The carina has a very strong tendency to spring downwards (residing chiefly in the thick- ened claw), while the staminal sheath and claw have a distinct tendency to spring upwards. The inner edges of the carina are strongly thickened and fit over the staminal sheath, thus keeping the carina from descending ; the alae form a perfectly horizontal platform, being supported on conical projections of the sides of the carina (cf. ‘ Bollazione od ernie ’ of the carina of /. macrostachya , Delpino, 1. c.) ; their inner edges, moreover, are grooved and fit over the thickened upper borders of the carina. This horizontal position seems to me to assist in keeping the flower from explosion in two wa ys, first, because the alae, if they are to allow the carinal edges to move outwards, must be twisted outwards in a plane which is the one in which they are expanded instead of being simply bent in a plane at right angles to their own surface, as would be the case if they were in the ordinary alar position, and, secondly , because the resultant of their weight (and that of a small insect stand- ing on them) is made to be directly downwards without any A frican and Madagascar Flowering Plants . 349 outward component, and is therefore counteracted by the staminal tube. In fact, in order to produce explosion, an insect must in- sert its proboscis between the thickened carinal edges, and so, by separating them, allow them to slip over the sides of the staminal sheath. If this is done by a needle an explosion occurs and pollen is scattered in all directions. This necessity of separating the carinal edges explains the fact that Meehan saw bumble-bees, hive-bees, and sand-wasps visiting the flowers without causing explosion. The Bombus at Philadelphia however could not have understood the flowers, as Delpino saw Bombus italicus causing explosion of /. macrostachya and being much alarmed thereby. (See also No. 346 Muller.) Sutherlandia fruteseens, R. Br. See Annals of Botany, vol. iv, 1890, p. 268. Lessertia pulehra, Sims (Figs. 66-68). The calyx-tube in this flower keeps the alae and carina together. The shape of the latter is peculiar ; its lower margin follows exactly the shape of the ovary and style, while its two upper margins are in contact above form- ing a vertical narrow edge ( a — Fig. 68). On depression pollen emerges as a ribbon-like streak all along this edge (a — b). The stigma is protected by a circle of long stiff almost upright hairs which are depressed by the weight of the insect. Clitoria heterophylla, Lam . (Fig. 69.) The flowers are blue and, like those of C. Mariana , in- verted. (Trelease, ‘American Naturalist,’ vol. XIII, Nov. 1879.) The vexillum is large and forms a broad alighting place for insects : pollen is very early shed on a brush of hairs which covers the inner face of the style ; the alae and carina are united and move together so that when they are forced upwards by the insect, the pollen-covered style protrudes. The nectary is peculiar, in fact so far as I know unique in the order ; it consists of a reflexed collar-like ridge rising from the staminal tube and lying like a saddle upon the ovary. — 35° Scott Elliot . — On the Fertilisation of South. Fort Dauphin. Visitors \—Apis mellifica and other Hyme- noptera. Erythrina eaffira, DC ., and E. indiea, L. See Annals of Botany, 1. c. p. 267. Canavalia ensiformis, DC. (Figs. 70-71.) The large reddish purple flowers are very conspicuous. The vexillum is strongly reflex and the basal ends of the limbs are produced downwards into thickened pegs which occupy the space between the auricles and claws of the alae. There is a longitudinal bulging along each side of the carina, which is fitted above and below by the alae ; the auricles of the latter are also carried back below the vexillum and thickened in such a way that they fill up the entrance so that no honey can escape. On depression both style and stamens emerge, and in young flowers some of the pollen is thrown a considerable distance as the edges of the carina catch the stamens. Honey is abundantly secreted. Visitors : — Xylocopa violacea , also Lepidoptera. — Fort Dauphin. Phaseolus lunatus, L . The carina in this form is bent into a spiral forming one complete turn and a half. The flower is fertilized exactly as n e. g. P. Caracalla (see Delpino, Muller, No. 178). It differs from P. coccineus described by Farrer (MUller, No. 242) in the appendage to the odd stamen being perfectly symmetrical (cf. Darwin, Muller, No. 169). Visitors : — Apis mellifica and several Lepidoptera. Phaseolus adenanthus, Mey (Figs. 73~75)* In this flower there is a very close similarity to Canavalia. The lower basal ends of the wings of the vexillum are similarly thickened, but there is also a pulley-like thickening at its point of curvature ; the auricles of the alae lie between these two thickened parts of the vexillum and rotate round the lower one on depression, but as each ala has also a small horizontal spur from its lower margin which passes below the carina, and as the calyx is strong and leathery, the effect of African and Madagascar Flowering Plants. 351 depression is to cause the vertical section of the alae to become circular instead of elliptical^ and this causes the carina to separate widely above leaving free egress to the pollen-covered style which is only slightly curved. Visitors : — Apis mellijica , ab., also Lepidoptera (cf. P. diver sifolius) described by Foerste, Macleod, No. 151). Vigna triloba, W alp. This form shows a further advance in structure on Phaseolus adenanthus , as the vexillum is connected with the alae in three ways : first , by the thickened basal lobes of its wing, which fit in between the alar claw and auricle ; secondly , by a pulley-like thickening in the middle line of the vexillum (just where the broad part of its blade begins), and which holds the superior edges of the alar blades together ; and, thirdly , by another pair of thickened pegs which are developed between the other thickenings and run forwards and inwards, fitting upon the outside of the auricles of the alae. On com- parison with P. adenanthus , it is easily seen that in this species the single pulley-like thickening in the front of the vexillum has become double, so that the auricle of the alae is still made to work in a groove between the basal and medial thickenings of the vexillum. The vexillum-claw has on its lower sides two raised edges, which clasp the odd stamen (this is similar to that of Phaseolus ) in its broad part very firmly. The style emerges in this species through a small orifice at the end of the carina. Vigna angustifolia, Bth. The flowers are very unsymmetrical. The vexillum has the usual turned-in edges on its claw to clasp the odd stamen, and on its expanded limb there is a conical peg to the right of the midrib, about 4 lines from the base. The peculiar want of symmetry in the alae and carina seems due to the style, which begins (after the horizontal ovary) by a vertical portion, and is then suddenly bent over to the left at right angles to its course, being at the same time twisted, so that the upper surface becomes wholly inferior : a slight lip on its 352 Scott Elliot . — On the Fertilisation of South flattened extremity is the stigma. The right carina forms at the tip a spoon-shaped covering to the horizontal terminal part of the style : It has at the basal end an auricle which is covered by the auricle of the right ala, whose edges are turned over to clasp it firmly: on depression the right carinal half simply slips down and outwards over the style. The left carinal half on the other hand is pushed under the style at its extremity, so as to form a sort of pocket enclosing the anthers, and on its side about half-way down is a conical protuberance ; on depression the edge of the left ala catches on this pro- tuberance, and causes the left carinal half to rotate about a horizontal axis, the tip turning directly outwards. Hence, when an insect alights on the alae and is struggling to pass round and under the peg on the vexillum, it causes the right carina to slip down and the left to rotate, fully exposing the style and anthers, and in passing out (probably under the style) will produce fertilisation. I have often examined this flower, and never seen an insect or a ripe pod upon it, so that it is doubtful what insect visits it, but Xylocopa would cer- tainly be able to produce fertilisation. — Pretoria. Dolichos Lablab, Z. (Figs. 76-83.) A glance at the figures will show the fundamental simi- larity of the vexillum in this species to that of Canavalia , Phaseolus , and Vigna . The frontal pegs are very large, semi- circular in shape, and hold the upper edges of the alae closely together in the middle line. The sides of the thickened vexillum-claw have a cavity hollowed out in their thickness, and in this cavity lies the odd stamen : as may be seen from Fig. 78, it is impossible for an insect’s proboscis to enter above the odd stamen, so that in this case at any rate the odd stamen must be levered up as described by Farrer (loc. cit.) for Phaseolus coccineus , and not as suggested by Francis Darwin (loc. cit.) ; there is a conical peg on each side of the carina which fits into a very deep socket on the ala. The stigma (with the pollen-covered hairs below) emerges African and Madagascar Flowering Plants, 353 from a vertical slit facing the vexillum, and I find that after fertilisation it grows forward till it takes a position inclined at 1800 to its original angle. The nectary is in the form of a band embracing the stipitate ovary (Fig. 83). Rhyne osia crassifolia, Bth, This has a general similarity to Vigna and the rest of the Phaseoleae. The odd stamen is similarly expanded and clasped by the arching claw of the vexillum. The carina has longitudinal bulgings on the side, which are fitted by depressions of the alae above, and a short tooth developed from the inferior margin of the alae below. The carina is distinctly turned to the left towards the tip (cf. Vigna and Phaseolus ), and the style emerges with the pollen borne on a mass of hairs below it.— -Durban. Virgilia capensis, L , In this flower the stamens and style emerge simply. The alae overlap one another below the carina, and their auricles also fit over those of the carina above, while there are slight swellings on the carinal upper margins which are fitted by grooves on the alae. Hence on depression the carina opens out, leaving free passage for the style. Although the stamens are not united for more than one-tenth of an inch, they form practically a sheath, as the edges of the alternate stamens are expanded (overlapping the others), and hairs are developed along these edges. Visitors : — Xylocopa violaceal and another large bee very abundant. — Near Cape Town. Cotyledon ramosissima, Salm. The scales of the disc are in this species flat and mem- branous and stretch across the spaces between the projecting backs of the five carpels so as to form pockets which are usually full of nectar. The filaments of the stamens, at about 3 lines from the base, become suddenly much thickened and hairy, and as these thickenings fit closely together, they form a kind of roof completely covering the lioney-pockets. — Somerset East. 354 Scott Elliot . — On the Fertilisation of South Kalanchoe vertieillata, Scott Elliot , ined. The flowers are bright scarlet and appear to be pro- tandrous. Brexia madagascariensis, Lindt. (Figs. 85, 86.) The midribs of the petals are much thickened and be- tween them lie the rather deep hollows formed by the con- cave sepals. Honey is secreted by a yellow thickened patch on the lower sides of the filaments near their base and drops into these hollows or pockets between the midribs of the petals. The filaments and the four-lobed staminodial discs between them conceal these pockets, so that they are not visible from above. These four-radiate discs or rudimentary stamens are yellow and appear to secrete a little honey on their upper surfaces near the ovary, so that small insects coming to the flower would never suspect the quantity below but fly away contented. The stamens twist downwards as shown in the figure, but only gradually as they ripen, so that the dehiscing face of the anthers is towards the entrance to the inferior honey-pockets. The short style ends in a flat stigma. Visitors : — The sugarbird Nectarinia souimanga sucking honey ! Also by a species of clear-winged moth in great abundance and other insects. — Fort Dauphin, also Ambahy. Montinia acris, Z. Honey is secreted in the male flowers by a well-developed disc which is accessible to most insects. Visitor : — Allodape , sp. (apparently undescribed, No. 139). Mesembryanthemum rep tans, Ait. (Fig. Sya.) The petals are red and the expanded flower measures fully an inch in diameter : the stamens are united at the base and form a sort of circular palisade arching inwards over the dark-green circular nectary. Insects cannot pass through this barrier from the outside, so that they will usually alight either on the styles or on the disc, and will probably cause cross- fertilisation, though self-fertilisation is quite possible. Visitors : African and Madagascar Flowering Plants . 355 Hymenoptera : Apis mellifica sucking between the stamens. Diptera : a small sp. and Syrphus capensis. Coleoptera : Peritrichia capicola , P 'achy enema crassipes , and others. M. aristulatum, Sond. Similar to preceding species. Visitors: — Diptera: Lucilia argyrocephala , L ophonotis sp. Coleoptera: Anisonyx ursus , -4. longipes . Hydroeotyle Solandra, L. f This flower is very markedly protandrous. There is no vestige of the styles while the anthers are dehiscing, and when the former are ripe the anthers have usually fallen off. Nec- tary dark purple and very large. Visitors : — Lucilia argyro- cephala, and other Diptera. Pleetronia ventosa, L. The style projects well above the stamens ; the corolla has a ring of short woolly hairs just above a basal constricted portion which forms a cavity to hold the honey secreted by the top of the ovary. Visitors : — Apis mellifica , very ab., also a Bombylid.— Durban. Kraussia floribunda, Harv . The corolla has a narrow tube with spreading reflex lobes. The style ends in a thickened clavate extremity which is marked by longitudinal furrows ; whilst in the bud the anthers closely surround this thickened portion and shed their pollen on the grooves, so that when the flower opens the end of the style is thickly covered with pollen. Subsequently the stigmatic lamellae unclose. The arrangement is there- fore the same as in Campanulaceae. Visitors : — Lepidoptera : four species (373, 378, 380, 381), very ab., and also Planema protea . Hymenoptera: Apis mellifica. Coleoptera: two species. Pavetta obovata, E. Mey, and Canthium ob ova turn, Klot have practically an identical arrangement. Pentanisia variabilis, Harv . The flowers are arranged in capitula and those towards the exterior open first. They are also distinctly dimorphic ! In the first form the style is exserted and the stigma stands 356 Scott Elliot . — On the Fertilisation of South about two lines above the corolla, while the anthers are per- fectly sessile and included within a small dilatation of the corolla-tube just inside the throat : in the second form the filaments of the stamens are not quite i lines long, and during dehiscence their anthers are almost horizontal with their inner pollen-covered face directed upwards, while the style is slightly shorter than the corolla-tube, so that the stigma is included. The narrowness and length of the tube (6-7 lines) shows an adaptation to Lepidoptera, and near Pretoria I have seen various species sucking the flowers. Honey is secreted by a small ring round the base of the style. Diplopappus fruticulosus, Less. In the florets of the disc the ends of the style-branches are covered with short rough hairs which brush out the pollen : the branches remain in contact at their extremities but curve apart so as to form an arch. The stigmatic papillae are on the sides of the outer edges of the branches. It is hence very similar to Agathaea coelestisi Cass., described by Hildebrandt (Muller, No. 357), and not very unlike Chrysoeoma (Muller, ‘ Fert. of Plants,’ p. 323). The rayflorets have no hairs. Visitors : — A peculiar little fly with a very elongate head, very ab., also other Diptera. Aster tenellus, L. Similar to Agathaea coelestis and Chrysoeoma Linosyris (see Muller, 1. c.) Visitors: — Small Hymenoptera: Halictus vittatus , Sm. very ab. Diptera : Systocheilus mixtus , Dischistus heteroceras , Macg. Coleoptera : Peritrichia capicola . Relhania genistaefolia, E Her. and R. ericoid.es, Cass. The branches of the style (in the disc-florets) end in hairy flat tops which push up the pollen in the usual way. Osmitopsis asteriscoides, Cass. I found that in this species there was a differentiation in the disc-florets. The outer circle of disc-florets being alone fertile and having larger nectaries and less pollen than the others. Their styles were open moreover, long before those of the inner florets were ready. — Cape Town. A frican and Madagascar Flowering Plants . 357 Bidens pilosa, L. Visited by Pieris hellica. Cenia turfoinata, L. The fertile florets alternate with the rays, and the branches of their styles are directed inwards. Visitors : — Hymenoptera: small species (No. 189). Lepidoptera: one sucking. Coleop- tera : 3 species. Diptera : Syrphus capensis. Cineraria geifolia, L. Visitors: — Diptera: Syrphus cognatus, sp. nov., Systocheilus mixtus . Coleoptera : Dicranocnemis sallicollis. Euryops abrotanifolius, DC. Visitors : — Hymenoptera : Alio dap e , sp. nov., Halictus albofasciatus . Diptera : Lucilia argyrocephala and small kinds very abundant, Scatophaga hottentota , Spilogaster , sp. Coleoptera : several species. Gymnodiseus capillaris, Less. (Fig. 87 b.) The style of the disc-florets ends in a thick conical head, at the base of which is a pretty long circle of hairs to hold the echinulate pollen-grains. The surface of this cone is also roughened (really covered with small hairs) for the same reason. Visitors : — Syrphus capensis , also small Diptera, ab. Othonna dentata, L . and O. arborescens, L . similar to preceding. Dimorphotheea annua, Less. Visitors: — Hymenoptera: Cosila sp. Diptera: very ab. a minute species with elongate head, Lasioprosopa Bigoti , Bombylius lateralis , Lucilia argyrocephala , and many other species. Coleoptera: Anisonyx ursus , A. longipes , Dichilus dentipes , D. simplicipes , and others. Tripteris dentata, Harv. and T. ampleetens, Harv. (Fig. 88). The styles of the disc-florets end in short blunt conical extremities covered all over by little rigid teeth and bounded at the base by a circle of much longer hairs. (Hildebrand, loc. cit. p. 31, describes and figures Calendula arvensis , in which hairs seem to cover the whole of the style-extremity in the central florets.) 35S Scott Elliot . — On the Fertilisation of South Osteospermum moniliferum, Z. Visitors Hymenoptera : species of Halic tus ? Diptera : small species ab. Coleoptera : Mylabris capensis Tromeces linearis. Ursinia, sp. Visitors : — Coleoptera : Dichilus dentipes , very ab., Ani- sonyx ursus , A. longipes , etc. Cryptostemma calendulaceum, R. Br. The arrangement of the hairs on the style, and its shape, is very similar to C. hypochondriacum , Br. described by Hilde- brand (Muller, No. 357). The styles rise and fall as in Gazania pinnata, Less, (vide infra). Visitors : — Hymenoptera : Blalictns de cep tus, H. vittatus , and another. Diptera : Bombylius styli- cornis , Lucilia argyrocephala , Systocheilus mix tus, Dischistus heteroceras , and another. Coleoptera : Dichilus simplicipes , and others. Arctotis aspera, Z. A. acaidis has been described and figured by Hildebrand (Muller, No. 357). This species possesses the same cylindrical thickening at the end of the style and this cylinder has a basal circle of hairs, besides being covered all over by short rigid teeth. The style below the thickened part is highly elastic and can be stretched half its length without breaking (see Gazania). Visitors : — Coleoptera : Dichilus acanthopus , Hedybius , etc. Gorteria diffusa, Th. (Fig. 89.) The style ends in a thickened part similar to other Arctotidae, but there is a peculiar constriction at point c below which the hairs are larger (see Fig.). The hairs are a bright purple and the pollen-grains yellow through the occurrence of oil-globules in their outer coats. Gazania pinnata, Less. (Figs. 90 a, 90 b) The terminal part of the style is thickened as in Arctotis ; the thickening begins with a rim-like projection which bears a circle of rather long hairs ; the rest of the thickened part is covered with short curved upward-pointing hairs. The style- branches are papillose over their whole inner surfaces (cf. African and Madagascar Flowering Plants. 359 Hildebrand ; it seems not to be so in G. r ingens). The most marked peculiarity however is the delicate elastic portion of the style below the thickened extremity. One may on a sunny morning almost see the pollen being pushed up through the anther-sheath by the style, and when the latter has finished extending, it stands fully three lines above the anthers. However, after the pollen has been removed, it sinks till the open stigmatic lips are just above the anther- sheath. This sinking, moreover, seems to be due to a con- traction of the style (not to withering), as in the younger styles the cells are longer than they are in the older state. Visitors : — Hymenoptera : Halictus vittatus . Diptera : Systo - cheilus mixtas , Dischistus heteroceras. Coleoptera : Peritrichia capicola. Cullumia setosa, R . Br. The pollen is echinulate. The style terminates in a thickened portion as in Arctotis. Visitors : — Coleoptera : Pa - chy enema crassipes , Dicranocnemis sallicollis , Dichilus dentipes. Berkheya carlinoides, Wild. In the shape of the style-extremities and the matter of retraction, this is exactly similar to Gazaniapinnata. Visitors : — Coleoptera : Peritrichia capicola , and others. Wahlenbergia procumbens, A. DC. In this species pollen is shed on the hairy outer surface of the stigma just as in Campanula. Visitors : — Lepidoptera, ab. — Also ants stealing honey. Wahlenbergia capensis, A. DC. This species differs from the preceding in the peculiarly- shaped thickened extremity of the style. This is hemispherical with the broad surface uppermost, and it is upon it that insects usually alight. The bases of the filaments are flattened and triangular in shape, and their edges being turned up and hairy probably prevent the entrance of small insects. Microeodon glomeratum, A. DC. The anthers shed their pollen upon rather long hairs which cover the style. The bases of the filaments are tri- 360 Scott Elliot —On the Fertilisation of South angular and very ciliate at the edges. Self-fertilisation is possible, however, as the five stigmatic branches eventually coil over so much that if any pollen is left on the style they must come in contact with it. Visitors : — Lepidoptera : Erebia cassius sucking. Ants also visit the flowers. Scaevola Thunbergii, E . Z. The corolla has somewhat the appearance of that of a Lobelia . The tube is about 7 inches long, and covered internally with long hairs which are all directed backward ; it is slit along the upper surface (just as in Lobelia) and through the slit projects the style which, however, is bent forwards and downwards in its upper portion. The stamens dehisce some time before the flower opens. The style in this condition of the flower is shorter than the stamens, and ter- minates in a membranous cup about 1 1 lines in diameter and a line deep. The anthers are bent inwards over the edge of this cup, and their pollen falls into its cavity (at the bottom of which is the quite undeveloped stigma) ; after dehiscence, however, the style grows past the anthers, and the edges of the indusium are flattened together in such a way that the entrance to the indusial cup is now a narrow transverse (i. e. horizontal) slit. The way in which insect-fertilisation is effected can be clearly seen by gently pushing one’s finger under the style into the corolla-tube ; while pushing inwards the style simply becomes more and more curved back, but on gently drawing the finger back a ribbon-like mass of pollen is left on the finger. This is because the upper margin of the slit is longer than the lower, and is pressed against it when it is being pushed inwards. If any pollen is left in the cup, it is subsequently forced out by the developing stigma which when fully ripe separates the edges of the slit, and forms a broad surface (indistinctly bi-lobed), ij line long and a line broad. The flower is thus protandrous, and exhibits a strong affinity with Lobelia ; the indusium is exactly comparable to the circle of hairs in Lobelia , and as Urban (Muller, No. 751) states that its microscopical structure looks very much like a circle of African and Madagascar Flowering Plants. 361 hairs united side by side, we have no difficulty in understand- ing how it arose. (See also Fritz Muller in Muller, No. 353, Bentham in Muller, No. 84.) Visitors:— Near Durban, Hyme- noptera: Nos. 385,365,367,366,368^11 large bees about the size of a Bombns , and sucking legitimately® Also Nos. 366, 369, and 370 all attempting to obtain the honey by inserting their pro- boscis in the upper slit of the corolla. I found the basal part of the style very hairy, probably an attempt to prevent this robbery. At Fort Dauphin, Madagascar, Xylocopa olivacea , Elis Romendi , Apis mellifica , and another (No. 617). Lepidoptera : Thorania , Durban, Nos. 372, 380, and another sp. Fort Dauphin, a large moth, No. 615. Coleoptera : Durban, No. 371. Goodenia. I have been much struck by the exact similarity of the description of this genus, as given by Mr. Hamilton (Macleod, Nos. 180 and 186), with the preceding; but neither Mr. Hamilton nor Mr. Haviland seem to have observed the fertilisation by insects. Lobelia. The fertilisation of Lobelia Erinus , L., has been very thoroughly described by Farrer (Muller, No. 240). Lobelia decipiens agrees closely with it. I found on the lower lip two ridges ending in a slot or groove, which affords a firm foothold for the bee. (Cf. Trelease, Muller, No. 727.) Apis mellifica was busily visiting the flowers (near East London) ; it pushes its head half-way down the tube, and, on retiring, its head and thorax are covered with a broad band of pollen ; in so doing it seemed to me that it pushed the bases of the lower filaments aside and so caused a thrusting down of the anther-cylinder on the circle of style-hairs. (Cf. Delpino, Muller No. 360 ; and Urban, Muller No. 751*) Lobelia eoronopifolia, L . Also visited by a Hymenopteron at East London. Erica leeana, Ait. The corolla is of an unusual length, viz. about 9 lines. C c 2 362 Scott Elliot. — On the Fertilisation of South The anthers are united in a ring round the style just as in Erica Wilmorei (?) described by Trelease (Macleod, No. 546). Erica baccans, L . The corolla is practically urceolate, but the closely appressed sepals are so folded inwards that they divide the interior into four tubular canals. The processes of the anthers (both of one anther and one from each of its neigh- bours) project into these cavities, and, as they are remarkably broad and long, occupy almost the whole space ; when these are touched by an insect’s head and proboscis, they cause a rotation of the anther on its filament, and the insect will thus receive a shower of pollen from three of the anthers. This is a further development of the simple type of E. carnea (Muller, No. 592) and E. tetralix (Muller, No. 633). Erica purpurea, Andr ., E. Plunkenetii, L., and E. fascieu- laris, L . See Annals of Botany, Vol. IV. p. 270. Blaeria purpurea, L. The stamens and style protrude from the mouth of the corolla, but the style being longest must first touch an insect’s head. I saw a large fly busily visiting this flower, and plunging head and thorax into the corolla ; also numerous small Diptera and Coleoptera. Orchipeda Dregei, Scott Elliot (Figs. 90 £-94). The flowers are white with a slight yellowish tinge, and are almost three inches in diameter. The corolla-tube (about one inch long) is peculiarly twisted, just as if it had been made to turn through 90° round its own axis ; in consequence of this twisting (which occurs pretty late in development, for there is no torsion in young buds) the inside of the corolla- tube is hollowed out into five spirally running grooves, each of which opens to the outside above by a circular aperture between the thickened insertions of the stamens. The anthers are almost sessile and very horny in texture ; they are all in contact at their upper extremity, and form a small cone which projects out of the throat of the corolla ; each pair of African and Madagascar Flowering Plants. 363 anthers is also in contact by their basal lobes ; a slit is, how- ever, left between the tip and their basal ends as their sides are not quite straight ; pollen is produced chiefly by the upper part of the anther (above its insertio ), but a slight amount is also found in the basal lobes. The style ends in a thickened extremity of which the uppermost part seemed to be barren ; below the level of the polliniferous portion of the anthers, however, it bears a membranous ring, which is formed of ten coherent scales with free triangular tips ; these triangular tips are alternately opposite the thickened insertion of the fila- ments and the entrances to the above-mentioned spiral hollows ; those which are opposite the hollows are horizontal, and occupy most of the entrance whilst the others are reflex on the style. The true stigma appears to be underneath this ring, and is therefore protected by it from most of the flower’s own pollen. It secretes a sticky matter. We are now in a position to understand the mechanism of the flower. If a bristle is intro- duced into one of the circular openings, its tip follows the line of the corresponding spiral groove until it reaches the base of the flower and nectary ; during the insertion, moreover, it is in contact with the corolla-tube through its whole length. Im- mediately, however, one withdraws the bristle, it straightens and slips between the horny basal lobes of two anthers so that on withdrawal, being rendered sticky by the secretion of the style above mentioned, it removes the pollen heaped up on the top of the style. The triangular tip of the stylar mem- branous ring will scrape off any pollen which may be on the proboscis on entering the corolla-tube of another flower. Cross-fertilisation would be therefore effected by, for instance, the proboscis of a moth. Self-fertilisation, however, is not wholly excluded, as the pollen of the basal lobes of the anthers might easily come in contact with the stigma. Visitors : — Probably night-flying moths. Beetles (No. 467) are often on the flowers gnawing the corolla. Vinca rosea, L. (Figs. 95-97). The flowers are red and have a long corolla-tube, which is enlarged at the insertion of the stamens, but only half a line 364 Scott Elliot*— On the Fertilisation of Sotitk in diameter at the actual throat ( t in figure). The anthers are inserted just below the entrance and their tips converge or arch together. Behind and above each anther is a small brush of hairs (developed on the corolla), and these hairs form a sort of roof protecting the pollen from rain. The style ends in a flat top (si) upon which the pollen is shed. The stigma is below this, and in its lower part secretes a sticky substance. When a butterfly stands on the spreading limb and inserts its proboscis, the latter slips down the tube along and against the inside of the corolla-tube without touching the pollen-mass, but on withdrawing its proboscis the latter is straightened and passes over the viscid convex stigma, and as this involves effort it is forced to slip between two anthers, and so catches and brings out a good deal of pollen. This can be clearly proved by introducing a bristle in the flowers. Abundantly visited by numerous (at least eight) species of butterflies. — Fort Dauphin. I could not see any motion of the staminal filaments as found by Wilson (Muller, No. 781) for V. minor, which has also been beautifully described by Charles Darwin (Muller, No. 153). Gomphoearpus arborescens, R. Br . Visited by small mosquito-like Diptera in great abun- dance.— Table Mountain, June. Camptoearpus crassifolius, Dene., No. 2871, Herb. Scott Elliot (Fig. 98). The corona is in the form of a cup-like ring about a line high, but opposite the stamens it is prolonged upwards into conical teeth about one and a quarter of a line in length. The filaments of the stamens are united to the coronal cup and as their anthers, as usual, lie upon the mushroom-like head of the style, a narrow passage only is left underneath the overhanging head of the latter c, c (see Fig. 98). The retinaculum consists of a rather long sticky disc which is placed horizontally on the flat lower surface of the style- head, and is therefore inclined at an angle of 6o° with the appendices of the anthers to which it is attached (see Fig. d)» African and Madagascar Flowering Plants. 365 On looking down on the flower from above, five circular aper- tures are seen between the stamens which lead down to the base of the flower. In consequence of the fusion of the staminal filaments and corona there is therefore a circular gallery running round the base of the flower under the over- hanging style and the base of this gallery appears to be fleshy and secrete honey. Introducing a bristle into one of these circular apertures and bending it about as an insect would its proboscis, the disc becomes usually attached and on withdrawal brings out the pollen. When one does this there is a sudden motion of the pollen-masses which immediately spring forward so that they are in a line with the disc and bristle to which it is attached (whereas formerly they were inclined at 6o° to it). Hence on entering another flower the pollen-mass will enter the circular aperture and be in the right position to touch the stigma. Visitors Numerous Lepidop- tera : Junonia Rhadama , Closterus flabellicornus , Limnas chrysippus , sp., Acraea Zitya , and three other species. Hymenoptera : Apis unicolor and a sand-wasp form. Diptera : No. 50a. Coleoptera : No. 520. Belmontia eordata, E. Mey (Fig. 99). The tube of the corolla is 6 to 7 lines long, while the limb measures nearly 10 lines in diameter. The anthers are lodged in a slight swelling just below the throat of the corolla. The greatest peculiarity lies in the occurrence of two stigmata quite separate and distinct from one another. The first is on the extremity of the style and projects out of the throat: so far as I could see, it had normal, well-developed stigmatic papillae ; the second is about 2 or 3 lines below this and consists of two longitudinal ridges on the style about a line long : I thought I distinguished germinating pollen-grains upon it. There are peculiar round knobs on the tips of the anthers; in young flowers these are erect and surround the style, while in older flowers they are reflexed and hang downwards; they may secrete a sticky substance ren- dering the pollen adhesive. The second stigma seems to me 366 Scott Elliot. — On the Fertilisation of South a contrivance to produce self-fertilisation in case the first stigma adapted to cross-fertilisation should receive no pollen. Visitors: — Apis mellifica ? also a Bombylid, Pangonia angu- lata ? — Muizenberg, Cape Town. Taehiadenus. In this genus the stigma is well above the anthers. Honey is secreted by a minute ring round the ovary. Visitors : — Lepidoptera abundant. — Imerina and Fort Dauphin. Ipomoea palmata, Forsk. The stamens are united to the corolla for about 3 lines and by bending forward towards the style leave a sort of chamber below in which honey is secreted. The nectary is in the form of a ring round the ovary. The staminal fila- ments are very hairy and the pollen appears to drop on to these hairs. Insects creeping down the corolla will receive pollen on their back from the anthers in young flowers and touch the style in older ones. Visitors : — Apis mellifica and Coleoptera. — Fort Dauphin. Ipomoea Pescaprae, Roth . The filaments are not united to the corolla. Cf. Bur- ger stein (Macleod, No. 64 a). Bobostemon frutieosum, Buek. (Fig. 100.) The flower is distinctly protandrous. The stamens are of different lengths varying from 5 lines (superior) to 9 lines (inferior). A honey chamber is formed by the hairy pro- jecting bases of the filaments (h in figure). Subsequently the style elongates growing beyond the anthers. Visitors : — Hymenoptera : Xylocopa cajfira^ Apis mellifica , Ceratina sub- quadrata , Tetratonia longicornis. Coleoptera : Anisonyx ursus , A. longipes , Dichilus dentipes , D. simplicipes , Peritrichia capicola. For Xi. montanum, see Ann. of Bot. 1. c. p. 271. Lyeium capense, Mill, non Thunb. (Fig. 101.) This is extremely similar to Lyeium barbarum described by Muller. The nectary is a small ring round the ovary. Visitors: — Apis mellifica , ab. also various butterflies. — Fort Dauphin. African and Madagascar Flowering Plants. 367 . On Lycium see Muller, p. 426 and No. 590 III ; also No. 703 ; also L. tubulosum , Ann. of Bot. 1. c. p. 271. Craterostigma naniim. Bth. There is a short corolla-tube and a well-marked lower lip more than half an inch long. At its highest point, about two lines before the entrance to the tube, the lower lip is furnished with two yellow solid tubercles about a line high and half a line thick. The outer filaments are attached to the lower lip near the origin of these tubercles : the filaments themselves have a basal horizontal portion and then suddenly bend at right angles and converge together just under the relatively short upper lip. The inner filaments are short and also converge to a point 2 lines below the outer anthers. The two pairs of anthers are united severally and are some- what hairy. On depressing the lower lip by pushing the tubercles gently downwards, the upper pair of anthers is brought forwards so as to lie in the line of entrance to the corolla-tube. Such a motion of the stamens is as far as I know unique in Scrophulariaceae. Subsequently when the anthers have finished dehiscing, the stigma elongates and its two lips unclose in a position between the two pairs of anthers. Visitors : — a Hymenopteron, No. 342. Nemesia floribunda, Lehm. Visited by Apis mellifica which inserts its head in the spur and sucks the honey. In so doing, it must remove the pollen from the four anthers arranged above and below the stigma. The flower is probably protandrous. Nemesia barbata, Bth. (Fig. 102.) The calyx and pedicels are covered with stalked glandular hairs on which one finds the bodies of unnecessary insects. I was not able to satisfy myself whether honey is wholly secreted by the base of the ovary in this genus (so as to drop into the spur), but I could not make out clearly any secretion by the spur itself. 368 Scott Elliot. — On the Fertilisation of South Zaluzianskya coriacea, Walp. (Fig. 103.) In this genus the stigma projects out of the corolla-throat and must first come in contact with an insect standing on the limb. The two anterior stamens are exserted and their anthers are transverse or horizontal during dehiscence, while the posterior anthers are wholly included and their anthers dehisce parallel to the corolla-tube, lying close to its lower surface. The nectary is chiefly developed on the upper part of the ovary at the base of the flower. The length (14 lines) of the corolla-tube would lead one to suppose Lepidoptera to be the chief fertilisers of this flower. The limb appears to be closed over the corolla-entrance in dark or cloudy weather. Phyllopodium diffusum, Bth . The stigma stands well in front of the anthers and of the entrance to the corolla-tube. The longer stamens are ex- serted and dehisce outwards with anthers inclined at 450 to the horizon : the shorter stamens are almost wholly included and dehisce upwards. Visited by a long-tongued Dipteron remarkable for the extremely hairy yellowish brown abdomen. — Near Cape Town. Chaenostoma polyanthum, Bth. The style and anthers are both exserted in this species. One insect (? Odynerus , sp.), which I was able to watch, was standing tipon the style and inserting its head between the reniform anthers. Also visited by Diptera. — Somerset East. Manulea Cheiranthus, L. (Figs. 104, 105.) In this genus there is a very short style which only reaches about half-way up the corolla-tube. The anthers are both included in a slight dilatation just below the throat of the corolla. On looking at the corolla from in front, it will be seen (see Fig. 105) that the transverse section of the tube is not circular, but that, owing to a folding inwards of the lines of union of the petals, two canals are formed opposite the two upper petals down which an insect’s proboscis must pass c, c (see Figs.). The ridges between these canals and the canals themselves are continued inwards for about one line African and Madagascar Flowering Plants. 369 (that is past the insertion of the stamens). Each of the ridges bears three longitudinal rows of yellow clavate hairs. This arrangement is very complicated at first sight, but is really a simple and beautiful adaptation to cross-fertilisation. When an insect is inserting its proboscis, the curve in the latter will cause it to travel along these canals and quite out of the way of the stamens : moreover the hairs on the internal ridges, r, will also prevent any of the plant’s own pollen being shaken down the tube. On withdrawing the proboscis, how- ever, it will slip downwards (while straightening) amongst the hairs and stamens and cannot fail to be covered with pollen. The anthers of the two pairs of stamens have the same dif- ference in shape which occurs in Zaluzianskya (see above). A long watch did not enable me to find any insects on this plant. Manidea rubra , L. seems identical with the above species. Ilysanthes eapensis, Bth. (Figs. 1 06-1 08.) The corolla is much like that of Mimulus but the arrange- ment of the stamens is very peculiar. The two upper are erect and arch together so as to dehisce downwards on the back of an insect entering the flower, while the two lower have longer perfectly horizontal and straight filaments lying flat on the lower surface of the corolla. These latter are scabrous and have an appendage or seta usually pointing backwards at an angle of 450 to the filament, and which affords apparently a foothold for insects while entering. The flat triangular stigma lies above the upper anthers. Self-fertilisation is how- ever possible. The capsules when ripe become bent downwards at an angle of 450 to the stem. This appears to be due to growth taking place at the inner (stem) side of the base of the pedicel, where a small tubercle is formed. If * however , ripe capsules are not produced no growth takes place (cf. Hemi- meris sabidosa). Utricularia spartioides, E . Mey. The lower lip of the corolla forms an enormous spur with 370 Scott Elliot— On the Fertilisation of South the lateral margins slightly bulged and these margins are completely fitted and covered by the upper lip. The stamens lie close together against the upper lip, and the stigma is above them. A bee entering must touch the stigma before it reaches the anthers. The irritability of the stigma pointed out for U. vulgaris by Hildebrand (Muller, No. 356) and Beal (Muller, No. 44) is scarcely distinguishable in this species. Visited by a small Hymenopteron, Odynerus , sp. ? sucking and gathering pollen. Colea decora, Boj. (Figs. 109-m.) The flowers are an inch long and the corolla is at the throat 5 lines broad and only 3 lines deep. The style is well in front of the stamens and is additionally protected from its own pollen by a distinct upward curvature which in the young condition keeps it in contact with the upper part of the corolla-tube : if loosened from the corolla in this state, it bends back, as shown in the figure, proving that it has a distinct tension. The stamens have their filaments slightly curved and dehisce upwards. The corolla is white but dark red inside except the two longitudinal ridges, seen in section, Fig. no, which are bright yellow and are covered with hairs. These ridges are due to the arrangement of the petals in bud (see Fig. 1 l i). Visitors : — Birds, Nectarinia souimanga is very fond of this flower. Also various butterflies and moths (one species of clear-winged moth is a very regular visitor) as well as Apis mellifica collecting pollen.— Fort Dauphin. Rhytiglossa eekloniana, Nees. The peculiar twisting of the corolla-tube so that the anterior and posterior lips are reversed in position ensures that insects will enter above the stamens and style. The method of fertilisation is similar to that of Plectranthus. The two stamens are at first straight and dehisce upwards : after dehiscence they move sideways, and curl themselves round the lower lip of the corolla. The style then elongates till it occupies their former position and the stigmatic surfaces unclose. Visited by numerous Diptera and Hymenoptera. — Bedford. African and Madagascar Flowering Plants. 371 Asystasia gangetica, T. And. The corolla is rather like that of Digitalis but much smaller and somewhat contracted at the base so as to form a sort of honey-pouch. There is marked protandry : in the first stage the stamens are arranged in pairs close to the upper lip of the corolla, and dehisce downwards while the immature style lies behind and above them ; in the second stage first the two anterior stamens and then after an interval the two posterior bend sideways while the end of the style curves downwards and the stigmatic lips are open and ready for the pollen (cf. Stachys , see below). Visitors : — Hymenoptera : 8 spp. (Nos. 388-395). Lepidoptera : 1 sp. (384). Coleoptera : 1 sp. (378). — Durban. Rhinacanthus oblongus, Nees. This is markedly protandrous. The style in the second stage bends forward between the anthers and in so doing may effect self-fertilisation if all the pollen has not been removed by insects (cf. Delpino, Muller, No. 177). Visitors : — Lepidoptera. — East London. Braehystephanus cuspidatus, Scott Elliot (Fig. 112). The flowers are mauve in colour and there is marked protandry ; the final condition being that shown in the figure. Visitors : — Nectarinia souimanga not uncommon ! Lepidoptera : at least seven species including two species of Papilio . Hymenoptera : Apis mellifica , Icaria Rhodorae, and another, all stealing honey from holes bitten at the base of the flower. Oftia africana, Bocq . (Fig. 113.) The flowers are small and white and are strongly scented. There is a short and curved corolla-tube with a small spread- ing limb. The style is included and the stigma faces the upper side of the corolla-tube just behind the anthers, and yet, in spite of its apparent certainty, self-fertilisation is probably quite impossible ; first, because the curve of the corolla-tube is such that the anthers are not above the stigma but in front of it , and pollen cannot therefore naturally fall upon it : secondly, because the inside of the tube is largely covered by hairs, all 372 Scott Elliot . — On the Fertilisation of South of which point upwards, and by using a bristle, I came to the conclusion that the pollen (which seems to come out bodily from the four anthers) cannot be forced down the tube but is only removed on withdrawal. It is difficult to see how pollen can be introduced to the stigma as these hairs would tend to prevent it, but probably they eventually wither. Visitors : — Coleoptera : gathering pollen. Diptera ; a Bombylid ? Probably the main fertilisers are night-flying moths. Disehisma ciliatmn, Chois. (Fig. 114.) The flowers are marked with red and fairly conspicuous from their aggregation in a pretty long raceme. The corolla has a delicate tube about 4 lines long which is split half-way to the base. Probably this apparent splitting is due to the non-development of one petal which is represented as a small tongue at the end of the slit. There is a difference in the shape of the anthers ; the two upper anthers being horizontal and the two lower vertical (cf. Z aluzianskya , Phyllopodium , Maniilea). The style projects a long distance out of the corolla, and is curved with the concavity of the curve ap- pressed to the rudimentary petal. The flowers are visited by Apis mellifica which, as I saw clearly, plunged its head between the anthers and touched the stigma with its abdomen. The method of fertilisation is therefore identical with that of Chaenostoma (p. 368). Ocimum hians, Bth . The stamens and style are both widely exserted in this flower, but the latter lies well in front of and above the an- thers. The essential organs are not in contact with the lower lip because the staminal filaments curve upwards in a slanting direction. There is a hairy enlargement of the filaments in the throat of the corolla which probably completely excludes small insects from the honey. (Cf. Sprengel, who pointed this out in 1793, Muller, No. 702.) Synelostemon densiflorus, E. Mey . The mechanism and shape of this flower is very similar to that of Plectranthus Eckloni. The outer stamens roll African and Madagascar Flowering Plants. 373 forward and dehisce whilst the filaments are straight, then by a continuation of the rolling motion become bent back over the lower lip : the inner stamens follow suit and finally the style elongates and the stigma occupies the position taken by the anthers during dehiscence. The calyx is extremely viscid and hairy, but in spite of this ants are able to enter the flowers and steal honey. The nectaries consist of two short tongue-like projections behind and in front of the ovary. Visitors : — a Bombylius with a proboscis T9oth of an inch long, very abundant ; a large yellow butterfly, a small Odynerus ? gathering pollen but effecting fertilisation accidentally. — Perie Mountains. Synelostemon dissitiflorus, Btk. This is very similar to the preceding species. The nectary is in the form of four tongue-like pieces surrounding the ovary. Visitors: — Syrphus ? capensis. Pleetranthus Eckloni, Bth. The flowers are blue, and as the plant is sometimes eight feet high, it forms a very beautiful part of the undershrub in the Perie Bush. In the young state all the anthers are rolled backwards and included in the corolla-tube, but as the flowers ripen, the outer stamens uncoil and roll forwards dehiscing while the filaments are in a line with the corolla-tube : then by a continuance of the rolling motion they coil themselves round the lower lip. The second pair of stamens follow them and dehisce almost in the same position and then like the first roll themselves round the lower lip. Lastly the style rises and occupies nearly the same position as the stamens, while its stigmatic lips unclose and are ready for fertilisation. Visitors : — Apis mellifica collecting pollen ; a Bombylid sucking and effecting cross-fertilisation. Two Lepidoptera. P. fruticosus, Herit. A near ally of the above species has been described and figured by Hildebrand (Muller, No. 360).— Perie Bush. 374 Scott Elliot. — On the Fertilisation of South Pleetranthus Melleri, Bkr . The flowers are small and mauve with dark spots (honey- guides) on the upper lip. The four stamens in this species roll forward and dehisce together at a point opposite the entrance to the corolla-tube. Subsequently they continue the unrolling process and bend down on each side of the lower lip. The stigma then elongates and rises slightly. The nectary consists of both an anterior and a posterior ridge. Pleetranthus ealycinus, Bth. The corolla is covered externally with woolly hairs and has a very peculiar shape ; the tube is extremely deep and its axis is inclined to that of the pedicel. The lower lip has the two sides bent up so as to have a boat-shaped appearance, something like the carina of a leguminous flower : when at rest the two edges of this carina fit between the lateral petals which form cushion-like ridges on either side of the broad opening of the corolla-tube and so completely close it. The essential organs are contained in this carinoid lower lip. An insect must alight on this carina or lower lip and force it down, and whilst doing so the stamens emerge and dust its sides with pollen, whilst in older flowers it must also be touched by the stigma. The lower lip flies back elastically after depres- sion and it requires considerable force to press it down. The nectary is chiefly developed on the front of the ovary and a small pinching-in of the corolla just before it forms a sort of cup in which honey accumulates. The woolliness of the corolla is to prevent insects biting an entrance to the tube. I found many flowers with a small hole at a point just above the nectary, and caught a small fly with a proboscis x3^ of an inch long sucking through these holes. Pleetranthus laxiflorus, Bth . This species is remarkable for the sudden bend at right angles in the corolla-tube. The lower lip has the same boat- shaped appearance as in P. ealycinus and also the same tension which makes depression hard to produce. I watched a bee enter and could see that it required considerable force to African and Madagascar Flowering Plants. 375 press the carina down. The stigmatic lips do not appear to unclose till the anthers have dehisced. Pleetranthus tomentosus, E. Mey. Agrees with preceding species. P. glaucocalyx, Maxim, has been described by Loew (Macleod, No. 394) and appears to belong to the type of the three last-described species. The genus contains therefore two quite distinct modifications leading to different ways of fertilisation. The first marked by the very strong protandry and coiling of the stamens round the lower lip, and the second by the elastic boat-shaped lower lip including both stamens and style. Stachys Lyallii, Benth. This has practically the same arrangement as S. palustris , L. (cf. Muller, Nos. 178, 702). In the first (male) condition the lateral outer stamens have their anthers in front of those of the median stamens and dehisce in that position : they afterwards twist sideways so that their anthers are carried out of the way and drop off outside the flower. The median anthers then bend a little forward and dehisce, afterwards turning sideways like the outer lateral ones. Last of all the style bends considerably forward and the stigmatic lips open. Visitors : — Apis mellifica , probably Ody nevus spp. Lepi- doptera: T sp. (No. 284)— Hebron and Klerksdorp. Stachys eafifra, E. Mey> and S. aethiopiea, L. (Figs. 1 1 5-1 17.) Seem to have exactly the same arrangement as the pre- ceding species. S. annua, L. as described by Schulz (Macleod, No. 516) is quite similar, but as he makes the extraordinary statement that spontaneous self-fertilisation is easily possible, I cannot understand his description. Surely this observer cannot have failed to notice protandry in this species. At any rate in no other species of Stachys is self-fertilisation possible so far as published observations go. D d 376 Scott Elliot . — On the Fertilisation of South Salvia africana, L. (Fig. 118.) The style stands in front of, or a little above, the extremity of the lower lip, and does not, so far as I could see, alter its position during the flowering. The lever-apparatus is of the ordinary type. Visitors : — Xylocopa cajfra , also Peritrichia capicola . — Wy nberg. Salvia stenophylla, Bth . There is a lever-motion of the stamens but it is not of a high type. The inner anther-lobes apparently even produce a little pollen, and the rotation is very slight, only sufficient to bring the outer anther-lobes in the direction of the straight line passing from the stigma down the corolla-tube. Visitors : — Pieris hellica and two other species of Lepidoptera. — Pretoria. Teucrium africanum, Thunb. Visited by Lepidoptera. — King William’s Town. Vitex Bojeri, Schauer (Fig. 119). The corolla is pink and covered externally with short hairs. The four anthers lying close together project con- siderably out of the corolla-tube while the stigma always lies behind them. The nectary is a small rim round the base of the ovary. — Fort Dauphin. Hepenthes madagascariensis, Poir. I found the pitchers in this species to be usually from a third to half full of the decomposing remains of insects. In almost every pitcher there are live maggots or worms, which I could not manage to preserve, apparently living on the remains. Amongst the insects I selected at least thirteen species of Coleoptera (a species of Hoplia being very abundant) ; ten species of Lepidoptera ; seven kinds of Hemiptera ; four species of Hymenoptera, of which one was a sand-wasp nearly an inch long ; twelve species of Diptera, including specially Tipulae, green flies, and house- flies ; two Grasshoppers ; two Dragon-flies ; and one spider. — Fort Dauphin. African and Madagascar Flowering Plants. 377 Leucadendron adseendens R. Br. (Figs. 1 20-131). The flowers are unisexual and dioecious. In the male flower, the pollen is shed upon the barren style which is marked by eight faint longitudinal grooves corresponding to the anther-loculi, and which are homologous to the deep ones on the style of Protea : it appears to be held upon the style, however, mainly by a yellow, sticky secretion in the epidermal cells of the latter. The female flowers have the stigmatic surface always inclined outwards, usually at about 450 to the style. For Protea and Leucospermum , see Ann. of Bot. Vol. IV, No. xiv, p. 274. Serruria congesta, R. Br. (Fig. 122.) The sepals in the bud are closely united over the tip of the style. If they are touched when the flower is ripe, they spring sharply back and immediately become strongly re- flexed, showing that their outer surface has a stronger tension than the inner. A certain amount of pollen is scattered by this sudden separation, but most is held on the thickened style-extremity, which is faintly ribbed and seems also sticky. The stigma lies in a minute depression at the summit of the style, and does not ripen till after the pollen has been in large part removed. The anthers end in barren tips, t. Visitors : — Apis mellifica and other Hymenoptera. Pterygodium alatum, Sw. (Figs. 123-126.) In this species the posterior sepal and petals are connate into a helmet-like hood, the ‘galea’: the labellum and column are adnate, and form what is called the ‘ lamina,’ the shape of which will be clear from Fig. 123 (the view in front) and Fig. 124, a longitudinal mesial section. It consists of an upright column blocking the entrance to the galea, and in the lower part of a broad membranous bilobed wing, which on both sides turns slightly sideways so as to be visible in the longi- tudinal section. The anther and stigmata occupy the cavity of the galea behind the upright part of the lamina, and a deep groove which is lowest in the middle (i. e. at insertion of lamina) separates them from it. The two lobes of the anther D d 2 37$ Scott Elliot.— On the Fertilisation of South and stigmata are widely separated from one another and as seen from in front appear as two little projections above the lateral wings of the lamina (see Fig. 126, a, c). Honey appears to be secreted at the point n, which is a most unusual position, corresponding, as it apparently does, to the missing stigma, and being exactly behind the middle point of the lamina ; the groove already noticed leads down to this point over the lateral wings of the labellum, and obviously is the path by which an insect’s proboscis much reach the honey. This explains the position of the disc which is exactly at the en- trance to the groove (see Figs.), and, as may easily be shown by making a slender bristle travel down the groove, an insect’s proboscis must on withdrawal bring away the disc and attached pollinium : when this happens there is a slight curvature of the caudicle, bringing the base of the pollinium closer to the disc. The pollen-masses are transversely fringed and broad at the base, so that they will readily enter the galea cavity, but must on withdrawal catch on the stigmatic surfaces. What the use of the two pit-like cavities ( n, h) at the top of the lamina can be, I was unable to make out. Probably visited by some Dipterous insect. Angraecum superbum, Pet. Th . (Figs. 127-129.) The structure of this flower can be readily understood from the figures. The labellum is hood-shaped, and pos- sesses a thickened crest (cr) seen in section (Fig. 128) on its inner face. There is a pit or ditch excavated in the column between the spur entrance and the anther. The latter is raised on a round c boss,’ as seen from the outside (really the top of the column) ; the disc lies in a narrow groove at the highest point of this ‘ boss,’ just in front of the pit and en- trance to the spur. The method of fertilisation is very simple. An insect must stand on the sepals and petals, and insert its proboscis into the spur. As the crest, however, projects so much forwards, the proboscis (being also naturally curved) must be made to slip over the groove o, and on retraction must take off the disc and pollinia. This can easily be verified by means African and Madagascar Flowering Plants. 379 of a bent bristle. On entering another flower the pollinia will be left in the ditch or pit, the sides of which are stigmatic. Visitors : — I found a male Nectarinia souimanga sucking the flowers, and certified that it removed at least one pollinium, but as the flowers are scented at night it is probably chiefly fertilised by night-flying moths, such as the Sphingidae (of whom some have proboscides eighteen inches long or more). Cf. Moore (Muller, No. 537), Darwin (Muller, No. 165). Disperis villosa, Swartz (Figs. 130-133). In this form the posterior sepal and the lateral petals are connate into a galea which has almost exactly the shape of a poke-bonnet (Salvation Army type). The anterior sepals spread out diagonally in front. The labellum has a narrow thread-like basal portion, and ends in a slightly thickened boat-shaped extremity which appears to secrete a sweet sub- stance. It is bent upwards and then folded back at a right angle so that this thickened extremity lies inside the galea and upon the top of the column. The column ends in the large anther-case, which is horizontal and reniform in shape. The end of the labellum lies in the groove of this reniform anther. The most striking peculiarity of the flower is the manner in which the anther-case terminates at both ends in front. The membrane of the anther-case at each anterior point is drawn out into a spiral ribbon which projects out of the opening to the galea, and is about two lines long : these two little coils stand further forward than the labellum which lies between them, and are close to one another. The cau- dicle of the pollinium lies along the inner side of their coils, and its disc is on the under surface of the extremity at d (Fig. 131). In consequence of this arrangement, the readiest way for an insect to reach the honey secreted on the upper surface of the thickened end of the labellum (point n, Fig. 132) is by passing its proboscis under the arching extremity of the coil, i.e. below the disc. In doing this, it must search for the nectary by bending its proboscis about, and cannot fail to touch the disc, which immediately clasps it firmly. On 380 Scott Elliot,— On the Fertilisation of South withdrawing the pollinium by a bristle in the way an insect would do, the pollen-mass immediately drops through 6o°, or even 90°, and if one now introduces the bristle with the attached pollinium below the coil of another flower, it is seen that this inclination brings it in contact with the stigmata which lie on either side and just below the labellum. I found that in a hundred flowers examined, six had one, and two both pollinia removed. Some of the numerous long-tongued Diptera would be quite able to fertilise this flower (cf. Bolus, ‘ Orchids of the Cape Peninsula ’). Mr. Weale has described a species of Disperis from the Kagaberg, but unless I misunderstand his description, the structure is very different from this species (Muller, No. 765). Moraea. The different species of this genus show a great deal of variation in some important characters. Thus in Moraea tristis, Ker (No. 1148 I)1, there is no very obvious difference between the external and internal perianth-segments, which together form a campanulate tube down which insects may crawl in any direction : moreover, the style-branches are short (though broad) and supported on a column fully 3 lines long. In Moraea tripetala , Ker (No. 1081 !) the internal perianth-segments have almost disappeared, while the style-branches are separate almost to their bases and each is so closely applied to its corresponding external perianth- segment as to form a complete tube down which the insects are obliged to crawl. All the species which I studied may be grouped between these two, and form a gradual series of transitions (Figs. 133 and 142). Moraea tristis, Ker (No. 1148 !) (Figs. 133, 134). Honey is secreted at the base of the external perianth- segment. Visitors very rare. Moraea edulis, Ker (No. 1199 !). The flowers are purple and the external perianth-segments 1 The species are so hard to distinguish that I have quoted my collecting numbers throughout. The originals are at Edinburgh or Kew. African and Madagascar Flowering Plants. 381 have a white dot at the tube-entrance ; there are three distinct longitudinal rowsof hairs along the claw. This is a dimorphic species (cf. Muller, p. 545). One form is exactly like another species, No. 1095 ! while in the other the arrangement is much like that of Moraea tristis, No. 1148! Visitors: — Anisonyx ursns and other Coleoptera. Moraea trieuspis, Ker (No. 1096! Figs. 135-137). The style-branches are supported on a very distinct column in this species. The internal perianth-segments end in a peculiar three-lobed tip (see Fig. 135), while the external perianth-segments are distinctly concave and possess at the base a small square scale which forms a pouch for the honey. Visitors : — Coleoptera : Anisonyx ursus , which I saw crawling down the external perianth-segment and sucking the honey. — Sea Point, Cape Town. Moraea angusta, Ker (Nos. 1095! 1150! 1198! Figs. 138- 140). The flower is large and in this species each style-branch and its corresponding external perianth-segment are closely approximated to form a complete tube as in Iris. The inner perianth-segments prevent the entrance of small insects at the base. In some cases however this tube was not complete (cf. Muller, 1. c. p. 545.) Visitors: — -Hymenoptera : Ceratina sp., ants stealing honey. Diptera : Pangonia angulata , Lucilia argyrocephala , and others. Coleoptera : Anisonyx ursus , Dichilus simplicipes , and another sp. (No. 186.) — Devils Mtn. and Washhouses. — Cape Town. Moraea papilionaeea, Ker (Fig. 141). Except for the presence of large internal perianth-seg- ments, this scarcely differs from the preceding. Visitors : — Apis mellifica , very ab. covering its back with pollen, visiting each segment of the flower and crawling backwards out of each (cf. Sprengel, 1. c. No. 702 and Muller, l.c. p. 54 5)> also ants stealing honey and Empis bivittata , sucking. 382 Scott Elliot . — On the Fertilisation of South Moraea tripetala, Ker (No. 1081 ! Fig. 142). In this form the style-branch and external perianth- segment form a perfect tube, while the internal perianth-seg- ment has vanished. Visitors : — Hymenoptera. Homeria elegans, Sweet. The flower is of a very simple type, similar to that of a Crocus but without the elongate perianth-tube which charac- terises that genus. The anthers are longer than the style- branches, which however being broad, project sideways between them ; the bifid teeth on the dorsal side of the style- branches are at first erect as in H. collina , but subsequently become reflex and pendulous (cf. Crocus , Henslow, Gard. Chron. Vol. V. p. 504, and Muller, ‘Alpen-Blumen,’ p. 56). Visitors : — Apis mellifica, , very ab., also Coleoptera. — Cape Town. Homeria collina. Sweet. In the typical form the stigmata are at first lower than the anthers, but eventually elongate till they are about a tenth of an inch above them. The segments of the perianth are reflexed at the apex, and it is chiefly on the reflexed part that insects alight. In the variety miniata , Bkr. the segments are erect, and insects usually alight upon the stigmata and then crawl down over the anthers. Visitors : — Typical form. Hymenoptera : a large ? Xylocopa (possibly accidental), three kinds of ants. Diptera : Syrphus , a form very like the house- fly, both efficient and two small sp. Coleoptera : Anisonyx ursus , Dichilus simplicipes. — Twelve Apostles, Cape Town. Var. miniata. Visitors : — Hymenoptera : Apis stealing honey from base of perianth. Diptera : 2 sp. unnamed. Coleoptera : Anisonyx ursus , A. longipes , Chilomene lunata , and another. — Muizenberg and Cape Town. Ferraria undulata, L. (Figs. 343, 144.) The perianth forms a capanulate tube about 6 lines deep and the horizontally spreading limbs are about 8 lines long with crisped wavy margins. Honey appears to be secreted by the very thick bases of the segments, and collects in longi- African and Madagascar Flowering Plants. 383 tudinal hollows on either side of the midrib. The anthers lie well below the style-branches, which are cut up into laciniae forming a sort of bush of papillae above the pollen. The colour is a sort of lurid purple with yellow blotches and appears very attractive to saprophytic flies, e. g. Scatophaga hottentota , Chrysomia regalis , Lucilia , sp., and others. Some- times these alight on the laciniae of the style and sometimes on the perianth-segments. — Botanic Garden, Cape Town. Romulea. The general method of fertilisation in this genus is almost exactly similar to Crocus (cf. Muller, ‘ Alpen-Blumen,’ p. 56) ; but the style-branches are divided and the neighbouring stigmata project in pairs between the anthers and not (in those I saw) above them (cf. Benth. and Hook., Gen. Plant, p. 694). Honey is secreted by the base of the filaments and is usually protected from rain by hairs on the filaments, or perianth- segments. A tube similar to that of Crocus is found in all stages of development in the various species. Romulea rosea, Eckl. (Fig. 145.) There is a short tube in this form ; the throat of the perianth is yellow with black honey-guides, while the general colour is a deep scarlet. Visitors: — Allodape pictifrons. — Near Cape Town. Romulea hirsuta, Eckl. The flowers are pink, but in most points very similar to the preceding species. The sepals have strongly marked black lines on their lower surfaces which may be honey- guides for insects creeping up the flowers. Visitor: — Halictus, sp. Romulea bulboeodioides, Eckl. Flowers white, very similar to the preceding. I never saw any flowers with the style twice as long as the anthers such as those found by Battandier (Bull. Soc. Bot. de la France, t. XXX. p. 238). Galaxia graminea, Thunb. (Fig. 146.) In this form the stigmata are well above the anthers. 384 Scott Elliot . — On the Fertilisation of South The very long perianth-tube distinguishes this genus from Homeria and Romulea . Honey is secreted (so far as I could see) by the base of the perianth-segments and it is hard to see of what possible use the long tube can be to the plant (cf. Sprengel, on Crocus, Muller, No. 702). Visitors : — Anisonyx ursus and two species of small Diptera. Aristea pusilla, Ker. The flowers are extremely small and fugacious. They are rendered unsymmetrical by the excentricity of the style, which being relatively very long falls over to one side. The flower-axis is almost vertical. Francke (Macleod, No. 156) has described and figured this species correctly in his Inaugural Dissertation. Visitors: — Hymenoptera : Halictus, sp. Diptera: Lucilia , sp. Coleoptera : Anisonyx ursus (all of which are under five lines long). Aristea spiralis, Vahl. (Fig. 147.) The flowers are almost one and three quarters of an inch in diameter. They are markedly zygomorphic and compared with Gladiolus and Antholyza show exactly the same difference that one finds between Plectranthus and S tacky s. The style is almost straight and lies on the lower part of the perianth ; it is much longer than the stamens whose dehiscing face is directed upwards. Insects enter the flower by passing above and over the anthers and style. In consequence of the rigid and broadly inserted spathe, the flowers are obliged to come out on the other side of the stem, viz. at 1 8o° inclination to their natural position. In young buds, the stamens are quite regular, and the twisting by which the lateral stamens are made to dehisce upwards and not outwards, takes place very late ; in some buds, in fact, which opened in my room, it did not take place at all. Visitors : — probably Xylocopa caffra . — Wynberg. Hesperantha falcata, Ker. There is a narrow cylindrical tube, fully 5 lines long in mature flowers, which is full of honey. As the flowers open and are scented in the evening, they are probably visited by night-flying moths. African and Madagascar Flowering Plants. 385 Ixia graminifolia (Fig. 148). There are only two or three flowers at the extremity of the long pendulous stalk. The perianth has a very narrow tube, 2-3 lines long, ending in a campanulate limb about half an inch in diameter. The filaments are only one line long, and the subulate style-branches project between the anthers and rest upon the perianth-segments. Ixia excisa, Thunb . (Fig. 149.) In this species the perianth-tube is 7 lines long. The style is well above the stamens, and as the perianth-limb is only about 3 lines in diameter, insects probably alight on the style and not on the perianth as in the preceding species. I found one Dipterous insect acting in this way. I have, how- ever, found the flowers fully expanded so as to be nearly 8 lines in diameter, and in such a case, the fertilisation is pro- bably the same as in the preceding. Ixia columellaris, Ker. The perianth-tube is long (5 lines), and rather slender; the limb is campanulate or almost stellate and measures 13-14 lines across. The style-branches appear between and about half-way up the anthers. The filaments are fairly long and united both to one another and the perianth, so that entrance to the honey in the tube can only be obtained by passing the proboscis between the anthers and inside the tube formed by the filaments. G-eissorhiza seeunda, GawL (Fig. 150*) The perianth-tube is extremely short. There is also a distinct tendency to zygomorphy ; thus the anterior external perianth-segment is distinctly longer than the other two and the two anterior-lateral inner perianth-segments are broader than the others. The style moreover is longer than the anthers and bent upwards, lying above them as in Gladiolus . The anthers, however, dehisce extrorsely, and are quite regular. Visitors : — Apis mellifica , Halictus , sp., and another (No. 194), also Bombylius lateralis . — Wynberg. 386 Scott Elliot.— On the Fertilisation of South Freesia xanthospila, Klatt . The style is longer than the anthers before the latter begin to dehisce. Hence a bee beginning, as it usually does, on the oldest flower, will first touch its stigmata producing cross-fertilisation, and as it goes along the spike, will become well covered by the pollen of the younger. It can scarcely avoid fertilising the second and third flowers with pollen from the first however. — Visitors : — Apis mellifica , c. p., ab. — Cape Town Gardens. Lapeyrousia corymbosa, Ker. The flowers are arranged in a dense corymb and are usually mauve with a white star in the centre, bordered by dark purple lines. The flowers are markedly protandrous ; in the first stage the style with closed branches rests on the perianth, while the stamens are erect in the centre of the flower and their anthers dehisce upwards. In the second stage the style straightens, becomes upright and stands in the centre of the flower with its branches very widely open. Self-fertilisa- tion is possible, but only during the straightening process. Visitors : — Hymenoptera : small species of Ceratina. Diptera : Pangonia angulata } Forsk., another fly (much like the blue- bottle). Coleoptera : Anisonyx ursus , abund. ( Pangonia , a large Bombylid, particularly abundant and visiting the flowers in a very thorough and conscientious way.) Melasphaerula graminea, Ker (Fig. 15 1). The flowers are small, and the perianth is distinctly zygomorphic. The three inferior perianth-segments form the alighting surface for insects, and their edges are peculiarly turned upwards and undulate : the three upper segments are almost erect : there is a very minute perianth-tube usually full of honey, and entrance to it is obtained by two minute openings on either side of the anterior stamen. Visitors \~Altodape sp. nov. (a very small Hymenopteron). Syrphus capensis . Sparaxis grandiflora, Ker (Fig. 152). This flower really belongs to the Gladiolus-type, but there are some interesting peculiarities. First, the flowers are not pendulous, but inclined backwards towards the axis on which African and Madagascar Flowering Plants. 387 they are supported. The style is long (about one inch) and its branches when open are on the same level as the tips of the perianth-segments, and afford a convenient point for the insects (usually beetles) to alight upon. The wide infundibular perianth ends in a short tube about 3! lines long, which is full of honey. The stamens, however, have a special arrange- ment ; for while the odd stamen is turned back towards the style and curved so as to have its dehiscing face directed for- wards, the two lateral stamens are so twisted (through i8o°) that they dehisce introrsely, so that the entrance to the honey- tube at a (see Fig.) is surrounded by three dehiscing anthers. This is, in the case of the lateral stamens, an advance on Gladiolus in which these anthers are only turned through 90°. Visitors : — -Anisonyx ursus and A. longipes% both very ab. (Usually this beetle seizes hold of the two lateral stamens by its hind claws and swings itself down into the centre of the flower, and in doing so its hairy back becomes covered with pollen. Self-fertilisation occurs when two are in the same flower and chasing one another round it.) Tritonia squalida, Ker . This form is rather like Sparaxis , but the lateral stamens are not so much twisted and the style usually lies against the lower part of the perianth. Babiana spathaeea, Ker (Fig. 153). The arrangement is in this species quite similar to Gladiolus. The perianth -tube is only about 34 lines long. The two inferior perianth-segments are turned up along the edges, and these edges are crinkled and wavy (cf. Gladiolus pilosus). The stigmatic lips hang in front of the anthers and are also below them. It is visited by Anisonyx ursus , which lays hold of the upturned edges of the perianth by its hind claws. The length of its hind legs will then bring the extremity of its back (which is covered with hairs) first against the bifid extremity of the style-branches, and then against the anthers. Self-fertilisation, however, is not excluded. — Kloof Road, Cape Town. 388 Scott Elliot . — On the Fertilisation of South Babiana plicata, Ker (Figs. 1 54-1 55). The perianth-tube is in this flower nearly eleven lines long. The stigma is at first well above the anthers, but self- fertilisation may be produced by the way in which the anthers curl upwards when withering (see Fig.) and by a slight sinking of the style. Visitors : — Anisonyx ursus also visits this flower, but it probably is not the most important visitor. — Sea Point, Cape Town. Babiana ringens, Ker. See Annals of Botany, Vol. IV. p. 278. Gladiolus. In this genus there appears to be great variation in the relative position of the style-branches and anthers which has led Treviranus (Bot. Zeit. Bd. XXI. p. 1) and Musset (Comptes Rendus, T. CVIII. No. 17) to consider the flowers as self-fer- tilised. There is no doubt, however, that the flowers are distinctly protandrous, as shown by Delpino (see Hildebrand, Bot. Zeit. Bd. XXVIII. p. 670), and this clearly appears from Musset’s own account of the same species ( G . segetum). My own observa- tions (on G. pilosus , gracilis , and inflatus') led me to conclude, first , that the anthers always begin to dehisce before the style- branches have unclosed ; secondly, that there is in most flowers a second stage in which the open mature stigmata lie quite in front , though sometimes below the level of the anthers (Fig. 157) ; and thirdly , that self-fertilisation can only take place in such conditions as those drawn (see Figs. 158, 159), where the style-branches have finally been brought against the anthers either by themselves curling back or by the gradual sinking of the style itself. Gladiolus gracilis, Jacq. (Figs. 160, 1 61.) The mauve-coloured flowers of this species have the edges of the inferior lateral perianth-segments turned upwards so as to form four crinkled ribs running into the base of flower ; Anisonyx ursus makes use of these edges to haul itself laboriously inwards. Its hairy body is adapted to African and Madagascar Flowering Plants. 389 convey the pollen, and I have often found its back covered by it.™ North West Side Lion’s Head, Cape Town. Gladiolus pilosus (Figs. 156-159). Very similar to above and probably fertilised by the same insect. — Houwhoek. Gladiolus inflatus, Thunb. (Fig. 162.) The perianth has a remarkable similarity in shape to that of the Foxglove, and probably is visited by large bees. — Houwhoek. Gladiolus longicollis, Baker. The perianth ends in a tube 3*5 inches long and the flowers are visited by the Spurge Hawkmoth (on the authority of Mr. Medley Wood). — Natal. Antholyza. See Annals of Botany, Vol. IV. p. 277. Xridaceae [general remarks) 1. From the preceding it follows that there is really a very strong similarity in Homeria , Ixia, and Romulea , and if we were to take a sort of generalised Romulea as ancestor, the other genera would naturally group themselves into main lines of development, which are represented by Moraea and Gladiolus respectively. In the first line of development the species of Moraea afford a nearly perfect series of transitions from a form not very far removed from Homeria to one almost as highly specialised as Iris itself. The two main features in this evolution of Moraeas are, first, the gradual disappearance of the internal perianth-segments. Now Heinricher (Sitz. d. Kon. Acad, der Wiss. Wien, Bd. LXXXVII. 1883, p. 114,) points out that this inner perianth- circle does not appear till very late in the development of the flower (after that of the stamens); hence we can perhaps see how 1 One can scarcely regard Weismannism as anything but a theory unsupported by facts. I therefore maintain the following suggestions, based on undoubted facts, which may to a certain extent explain the origin of variations. 390 Scott Elliot —On the Fertilisation of South a form being early visited by insects might begin to form its seeds before this inner circle was complete. It would have in this way an advantage, and the inner perianth-segments would become permanently more and more checked in development till they disappeared altogether. The second great distinction is the enormous development of the style-branches, and here one may get a little nearer to the solution of the question. In almost all Iridaceae the stamens are fully formed before the style has finished grow- ing ; and this late growth of the style is one of the most striking features of the order. In Sparaxis , e. g., the young style lies feebly on the sides of the perianth, but as it becomes mature rises up, and stands eventually quite upright. Hence in flowers with a perfectly vertical axis we see how, if this excessive growth of the style late in life is any advantage, there would always be favourable variations arising. More- over the separation or splitting of the style-branches down to their very base which characterises some Moraeas, is not entirely inexplicable, for their weight must tend to produce this result. In the zj^gomorphic or Gladiolus-line of development there are also transitional forms. Geissorhiza secunda , Ker, tends in that direction and in a (possibly abnormal) form of Babiana (B. stricta var. v-illosa fide Prof. Macowan) I found the stamens quite straight and the style-branches appearing between the anthers just as in Romulea ! The greater development of the lower perianth-parts is of course a common feature of zygo- morphic flowers, but I thought I found that in those where this was most marked the upper perianth-segments were in the direction of the incident light and the lower transversely inclined to it. Of course the action of gravity would equally afford an explanation. At any rate in Babiana ringens , where the upper perianth-segments are much larger than the lower, the inclination of the flower is such that the lower are in the direc- tion of the incident light and the upper transverse to it. In Aristea spiralis there is the same zygomorphy of the perianth, but the parts are morphologically different. The twisting of the filaments in Gladiolus , by which the anthers are made to African and Madagascar Flowering Plants. 391 dehisce downwards, might be explained by the weight of the latter, which would tend to pull them into the position they assume. I append a list of the literature dealing with the family. Crocus.— Henslow, Muller No. 337 : Sprengel, Muller No. 702 : Reid Macleod, No. 476. Iris. — Muller, 1. c. p. 543 : Sprengel, Muller No. 702 : Kickx, Macleod No. 387(not seen) : Focke, Macleod No. 131 (not seen): Heinricher, Macleod No. 193 : Ludwig, Macleod No. 324: Licopoli, on pollen-grains only, Macleod 282, 283, 284. Cypella. — Muller No. 597 : Muller, F., Macleod No. 419. Romulea. — Battandier, Mac- leod No. 42. Aristea. — Francke, Macleod No. 1 56. Gladio- lus.— Muller, 1. c. p. 548: Sprengel, Muller No. 702: Trevi- ranus, Muller No. 742: Delpino, Muller Nos. 178 and 360: Arnaud, Muller No. 9: Focke, Macleod No. 131 (not seen): Meehan, Macleod No. 380 : Musset, Macleod No. 435 : Urban, Macleod No. 560. Wachendorfia hirsuta, Thunb. The structure of this species is almost the same as that of W. paniculata described and figured by Mr. Wilson (Trans, and Proc. Bot. Soc. Edin. Vol. XVII). I found it abundantly visited, on the Cape Flats near Kenilworth, by Apis mellifica , which however usually misses both stamens and style. Also Xylocopa caffra which was effecting fertilisation. Myrsiphyllum asparagoides, Willd. The filaments are triangularly flattened at the base, and thus form a sort of pouch in which a great deal of honey is secreted. Visitors : — Apis mellifica , very ab., s. and c. p. — Near Cape Town. Kniphofla aloides, Moench. This has been so thoroughly described by Stadler (; Beitrage zur Kenntniss d. Nectarien,’ Berlin, 1886) that there is little further to give. I found the colour to be in younger flowers a deep red with the base and midribs darker, while in the older flowers as they fade and become closely appressed to E e 392 Scott Elliot.— On the Fertilisation of South the peduncle it changes through pink to a light orange-yellow or almost white, so that if, as I think, it is fertilised by Nectarinae, this is of advantage as showing the birds which to avoid ; I never found bees in South Africa entombed in the perianth (Macleod, No. 274 a).— Somerset East. Lachenalia tricolor, Thunb . Bees frequently bite holes in the perianth of this species and so steal the honey. — Cape Town Gardens. Albuea major, L. (Fig. 163.) The three inner perianth-segments are closely appressed to the style which projects a little beyond them ; their ex- tremities are abruptly bent inwards and this incurved portion (one line long, two lines broad, and about half a line thick) is movable at the bend (pt. a Fig. 163). The lower part of the inner filaments (f) is flattened and about a line and a half broad, and this flat basal portion stretches across the groove formed by the projecting lobes of the ovary, so as to form a pouch for the honey which is secreted by the base of the ovary ; at a distance of one and a half lines from the base, however, the edges of the flat filament are brought inwards so as to form a narrow canal (f2) which is the entrance to the above honey-pouch, while the uppermost part of the filament again flattens out and supports the freely movable anther, whose extremity lies beneath the incurved end of the inner perianth- segment. On pushing the inner perianth-segment gently away from the ovary, the tip of the anther is held by this incurved piece and the anther rotates on its filament till it forms an angle of 450 with it. At the Washhouses, Cape Town, I saw Xylocopa violacea and another large black bee hanging on to the pendulous flowers and inserting their heads within the inner perianth-segments ; in so doing they will produce this rotation of the anther and their heads will remove most of the pollen, while they are inserting their proboscis in the filamentary groove and sucking the honey. This arrangement seems to me to prevent their backs being (except to a small extent) dusted with pollen as it is only the head that can African and Madagascar Flowering Plants. 393 come in contact with the projecting stigma. The outer stamens are barren, and fit over the ridges of the ovary. M r. Wilson has described and figured Albuca corymbosa , Bkr. (Macleod, No. 592), which seems extremely near this species. A. juncif olio,) Bkr., also described by him, appears to have an almost identical arrangement. A. major was described and figured by Sprengel (Muller, No. 702) in 1793. Androcymbium leue antiram, Willd . (Figs. 164-1 66.) The flowers are completely enclosed by the dome-shaped floral leaves ji , and within the cavity so formed many insects appear to take refuge. Each perianth-segment is wrapped round and (in the lower part) united to its filament in such a way that it forms a small pouch into which honey is secreted by a dark red swelling at the base of the free portion of the filament at n. The versatile anthers are per- fectly horizontal and dehisce upwards. They are usually considerably above the level of the stigma so that it is hard to see how self-fertilisation can be avoided. The insects most common in the cavity are Forficaria , always very abundant, a species of Anthicus , two other ants, and Heteroodeus pulchilus . These probably usually creep into the flowers by the base and may leave by the upper opening after crawling over stigma and anthers. — Rose-Bank, Cape Town. Baeometra eolumellaris, Salisb. The anthers end in a flat sterile top which probably tends to prevent self-fertilisation. Insects probably alight on the broad three-cornered summit of the ovary, and then collect pollen or crawl down to the base of the perianth. I could not find a distinct nectary, but the base of the perianth and filaments are of a brownish purple colour and appear secretive. Visitor : — Dichilus simplicipes. — Cape Town. Commelina nudi.fl.ora, L . The flowers are either male or hermaphrodite and are of a bright blue colour. The median inferior stamen is curved upwards and stands exactly in front of the rudimentary ovary; E e 2 394 Scott Elliot. — On the Fertilisation of South the two lateral inferior stamens have longer filaments which are also less curved upwards and hence their anthers, which are also fertile (though shorter than that of the preceding), lie below and more in advance of it. The two superior lateral stamens have short straight filaments and four-lobed barren connectives (though sometimes bearing a little pollen). The sixth stamen is always absent, though I fancied honey was secreted at the point where it should exist. In the female flower the stamens are as in the male and the style originally lies below them, subsequently curving upwards so as to lie in the path of the insect. Visitors: — Apis mellifica , very ab. — Fort Dauphin, Madagascar. Commelina tuberosa, L., C. Karawinskii, Mart ., and C. communis, L. have been excellently described and figured by Macleod (Botanisch Jaarboek, 2nd Jaargang, 1890, p. 143 ; English abstract). Except by the constant hermaphroditism and presence of the sixth stamen, they do not differ much from this species. C. coelestis , Willd. has been described by Muller (Macleod, No. 416) : also by Macleod, No. 343, and by Brei- tenbach (Macleod, No. 57). The male flowers being those that appear first from the spathe leads to the fertilisation of older flowers by the pollen of younger ones, and hence induces cross-fertilisation. African and Madagascar Flowering Plants. 395 EXPLANATION OF THE FIGURES IN PLATES XXI, XXII, and XXIII. Illustrating Mr. Scott Elliot’s paper on the Fertilisation of South African and Madagascar Flowering Plants. PLATE XXI. Carica Papaya. Fig. 1. Female flower. Fig. 2. Male flower, st. stigma, sta. stamens, n. nectary ; both reduced greatly. Viola decumbens. Fig. 3. Flower after removal of sepals and petals but with outline of spur and lower lip. ap. outline of anterior petal and sp. of its spur, s. spurs of anterior filaments, sti. stigma. Polygala bracteolata . Fig. 4. Flower from side with the lateral sepals removed. Fig. 5. Flower from above. Fig. 6. Style. s. sepal, p2 carina formed of fused anterior petals, with alighting brush v. and hairs hv at hinge or joint x , and along upper margin h^Pi posterior petals with over-lapping projection t. on right posterior petal, o. opening through which style appears, b. upper hollow on surface of style, h. lateral hollow, st. stigmatic surface. Muraltia Heisteria. Fig. 7. Longitudinal mesial section of an exploded flower. Fig. 8. Section in line x-y (Fig. 7) before explosion, se. sepals, ap. anterior, and pp. posterior petals, a.l. thickened ledge on inside of carina, cl. thickened claws of posterior petal, c. cavity of anterior petals enclosing essential organs. b. anterior vertical ridge on front of anterior petal, /x limb of anterior lateral petal, h half of limb of anterior median petal, s. sh. st. staminal sheath, .r. style, si. stigma, f. fingerlike projections on the ovary, n. nectary. Muraltia serpylloides. Fig. 9. Flower after sepals have been removed, lettering as above except x. hinge. Abutilon albidum. Fig. 10. Flower in longitudinal mesial section, h.c. honey cup of sepals, n. nectar tissue, sty. styles. Cyclopia genistoides. Fig. 11. Flower from the side with half the calyx and part of the vexillum-wing cut off. Fig. 12. and Fig. 13. Left ala from within and without respectively. Fig. 14. Flower with vexillum, calyx, and left ala removed. Fig. 15. Extremity of carina enlarged. Fig. 16. Staminal column towards the base viewed from above. s. sepals, ve. vexillum-claw, a. curved claw of ala, ad. alar depression fitting on corresponding depression cd. of carina, af. fold in ala fitting over pc. projecting lateral peg of carina, c. carina, ct. tubular cavity of carina in which style and stamens lie, x. opening through which style protrudes, n. opening to honey. 39 6 Scott Elliot.— On the Fertilisation of South Podalyria sericea. Fig. 17. Flower with calyx removed. Fig. 18 and Fig. 19. Alae from inside and outside respectively. Fig. 20. Carina and stamens. Podalyria calyptrata. Fig. 21. Flower viewed laterally, part of vexillum being cut away. Fig. 22. After removal of vexillum and right ala. Fig. 23. Left carina with essential organs in situ. Fig. 24. Transverse section along line a-b (Fig. 21). vc. vexillum-claw, al. ala, gr . groove on vexillum, se. reflex sepals, sti. style. Podalyria cuneifolia. Fig. 25. End of carina showing over-lapping or rolling together of alae and carina ; tu. tubular cavity. Podalyria canescens. Fig. 26. Part of flower from above with vexillum almost entirely removed. al. backward extremity of alar limb. Liparia sphaerica. Fig. 27. To show relative arrangement of calyx and vexillum seen from above (the latter being cut across). Fig. 28. Right ala from above. Fig. 29. Flower from the side with calyx and right half of vexillum removed. Fig. 30. Extremity of carina seen from in front : letters as above, except vr. rolled- in edges of vexillum, as. expanded anterior sepal, ac. alar claw, cc. carinal claw. Amphithalea ericaefolia. Fig. 31. Flower from the side. Fig. 32. Right ala from inside. Fig. 33. Left carinal half from outside. Fig. 34. Left ala and carinal half in situ from inside, cp. lateral peg of carina fitted by ag. deep socket on ala, ca. auricle of carina. Borbonia cordata. Fig- 35- Flower from side with calyx removed. Fig. 36. Right ala from inside. Fig. 37. Right carinal half from outside. agx. depression of ala fitting on upper groove, cgl of carinal half, ag2 lower margin of ala bent inwards so as to fit into cg2 lower groove of carinal half, b. the point to which the calyx extends. Lotononis prostrata. Fig. 38. Flower from the side with half the calyx removed. Fig. 39. Alae seen from above. Fig. 40. Left ala from outside. Fig. 41. Left carina from outside, ac. alar claw, a ., ad. groove on upper surfaces of left and right alae fitting on eg. deep groove on carina, az extremity of left ala wrapped sideways over right ala, cc. claws of carina. Lotononis involucrata. Fig. 42. Whole flower from the side. Fig. 43. Left ala from outside. Fig. 44. Left ala from inside. African and Madagascar Flowering Plants . 397 Fig. 45. Left carina from outside. Fig. 46. Alae and carina from below. Letters as above except au2 auricular connection of ala and carina ; au3 inferior bent-in edges of alae. Aspalathus aeimila . Fig. 47. Flower with calyx removed. Fig. 48. Left carinal half from outside. Fig. 49. Left ala from inside. Fig. 50. Stigma enlarged ; h. hairs. Aspalathus Chenopoda. Fig. 51. Longitudinal section of vexillum from inside. Fig. 52. Vexillum claw and basal lobes from behind. Fig. 53. Right ala and carinal half from outside. Fig. 54. Right carina from outside,/, joint or hinge of ala, cp. peg on carina. Aspalathus sarcantha. Fig* 55* Flower from side with half calyx removed; letters see above. Crotalaria capensis. Fig. 56. Alae and carina from above (left ala bent sideways). Fig. 57. Alae and carina from below. Fig. 58. Carina and ala from the side. Fig. 59. Vexillum-claw from below. Fig. 60. Cross section of ala and carina in line x-y, n. entrance to nectary. Crotalaria retusa. Fig. 6 1. Vexillum-claw seen from below. Fig. 62. Carina from above, tt. transverse thickened ridge, t2 thickened anterior pegs, h . honey-canal. Crotalaria humilis . Fig. 63. Flower from side with calyx removed. Fig. 64. The carina in situ. Fig. 65. Left carinal half separated from within. Letters as above. Lessertia pulchra. Fig. 66. Vexillum, calyx, and right ala removed. Fig. 67. Left ala from inside. Fig. 68. Outline of carina from above (line a-b). Clitoria heterophylla . Fig. 69. Longitudinal basal portion of flower in section to show peculiar saddle- like nectary n. Canavalia ensiformis. Fig. 70. Flower from the side with calyx removed. Fig. 71. Section along lin &a-b. Phaseolus adenanthus. Fig. 72. Longitudinal section of vexillum. Fig. 73 • Right carinal half. Fig. 74. Left ala from the inside. Fig. 75- Style, c. anterior callosity of vexillum, s. spur of ala fitting in groove g. of vexillum, r. spur of vexillum, st. stigma, b. brush of hairs. Dolichos Lablab. Fig. 76. Flower in longitudinal section. Fig. 77- Vexillum in longitudinal mesial section. 39 8 Scott Elliot. — On the Fertilisation of South Fig. 78. Section along line a-b. Fig. 79. Left ala from without. Fig. 80. „ from inside. Fig. 81. Carinal half. Fig. 82. Odd stamen from above and below. Fig. 83. Style, s. odd stamen, pl groove in ala, h. style-hairs, b. vexillum- limb, n. nectary, a. projecting corner of carina fitted by a 1 of ala, ph. hairs on lower part of style ; other letters see above. Quivisia grandifolia. Fig. 84. Longitudinal section of flower, j-. sepals, p. petals, sU staminal tube, a. anthers, si. stigma, t. barren tips of anthers. PLATE XXII. Brexia madagascariensis. Fig. 85. Longitudinal section through the flower. Fig. 86. Stamens and staminodes seen from above, s. sepals, p. petals, st. stamens, a. anthers, r. starlike staminodes, n. nectary, h. honey-pouch, m. midrib of petal in section. Mesembryanthemum reptans. Fig. 87 a:. Flower in longitudinal section, s. sepals, p. petals, a. anthers, n. nectary, si. stigmata, ov. ovules. Gymnodiscus capillaris. Fig. 87 b. Extremity of style enlarged, r. roughening of small hairs, h. lower circle of large hairs, p. pollen-grains. Tripteris amplectens. Fig. 88. End of style enlarged. Gorteria diffusa. Fig. 89. End of style, g. hairs with which it is covered, c. constriction near the base, y. yellow globules on pollen-grain, s. stigmatic papillae. Gazania pinnata. Fig. 90. Position of style in a 6 and b ? condition. Orchipeda Dregei. Fig. 90 q. Flower from above. Fig. 91. Anther-cone enlarged. Fig. 92. Corolla-tube (with limb removed) from the outside. Fig. 93. Same in longitudinal section. Fig. 94. Style-extremity, b opening into canals c. running spirally round inside of corolla-tube, a. anther, p. pollen, s. flat top of style, s.c. ring of mem- brane ending in g horizontal and v 1 reflex teeth, n. nectar ring, si. stigma. Vinca rosea. Fig. 95. Longitudinal section of flower. Fig. 96. Thickened end of style (enlarged). Fig. 97. Anther-pouch (enlarged), t. entrance to corolla, c. circle of hairs, a. anther, p. mass of pollen on top of style, si. stigma, r. membrane ring, n neetarial ring. Camptocarpus ? crassifolius. Fig. 98. Flower in longitudinal mesial section, p. petals, t. tube or cup and l. lobes of the corona, c. Canal running round below the thickened mushroom-like head s. of the style, n. nectary, f. filament, d. disc or retinaculum, p. pollen- mass, a. anther, si. stigma. African and Madagascar Flowering Plants . 399 Belmontia cordata . Fig. 99. Flower in longitudinal section. stx. first, st2. second stigma, a. anther with knob, k. Lobostemon fruticosum. Fig. 100. Longitudinal mesial section of flower, h. honey-pouch. Lycium capense. Fig. 1 01. Longitudinal section of flower, h. hairs on filaments. Nemesia barbata. Fig. 102. Longitudinal mesial section of flower. Zaluzianskya coriacea. Fig. 103. Longitudinal mesial section of flower, s. sepal, anx. first and an2 second pair of anthers, n. nectary, ov. ovary, sty . style. Mamdea Cheiranthus. Fig. 104. Longitudinal mesial section of the flower. Fig. 105. View of entrance to corolla from in front, c. canals or grooves on inside of corolla-tube separated by ridges r. ; ax first and a2 second pair of anthers, si. stigma, gl. glandular hairs of calyx. Ilysanthes capensis. Fig. jo6. End of flowering plant. Fig. 107. Base of pedicel,/, commencing to drop, t. tubercle, /. leaf. Fig. 108. Two lower filaments with setae s. Colea decora. Fig. 109. Longitudinal section of flower. Fig. no. Cross-section of corolla-tube at pt. /. Fig. in. Arrangement of free ends of petals in bud to explain ridges on corolla, se. sepals,/, corolla, a. anther, s. style, si. stigma, n. nectary, m. midribs of petals. Brachy stephanus cuspidatus. Fig. 1 1 2. Flower in longitudinal section (reduced), a. anther, si. stigma. Oftia africana. Fig. 1 1 3. Flower in longitudinal section (letters see above). Dischisma ciliata. Fig. 1 1 4. Flower (calyx removed) seen from above and slightly diminished in size. Stachys aethiopica. Fig. 1 1 5. Flower from side in first condition. Fig. 1 16. From in front during second stage. Fig. 1 1 7. From side during last p stage. ax first and a2 second pair of anthers. Salvia africana. Fig. 1 1 8. Flower from the side: the dotted lines show the position of the anthers. Siam, connective-lobe. Vitex Bojeri. Fig. 1 19. Flower in longitudinal section (letters as above). Leucadendron adscendens. Fig. 120. Female flower in section. Fig. 1 2 1. Male flower from side. si. stigma, a. anthers,/, pollen. 400 Scott Elliot. — On the Fertilisation of South Serruria conges ta. Fig. 122. Flower from the side. Letters as above, t. barren tips of anthers, f their filaments, b. bract, s. sepals. Pterygodium alatum. Fig. 123. Whole flower from in front. Fig. 124. Longitudinal mesial section of flower (enlarged). Fig. 125. Left half of lamina and anther seen from behind (enlarged). Fig. 126. Disc, anther-case, and stigma from in front (Part of Fig. 123 enlarged). gal. Galea, se. anterior sepals, lam. upright part of lamina ending in nectar- holes nh ; w. wing or membranous part of labellum, ac. anther-case, d. disc, si. stigmatic surface, n. nectary, gr. groove leading to nectary. Angraecum superbum. Fig. 127. Whole flower from in front, clinandrium removed. Fig. 128. Same flower in longitudinal section. Fig. 129. Rostellum from exactly in front: flower in same position as last. se. sepals, lab. labellum, h. hood in which it ends, sp. spur, cr. crest or mesial expansion of labellum, a. pollinium, pit. pit in which pollinia fall, 0. groove in which disc d lies, ov. ovary. Disperis villosa. Fig. 130. Flower from in front, natural size. Fig. 1 31. Flower in longitudinal median section (lateral sepals removed). Fig. 132. Anther and labellum from above. j1# posterior sepal or galea, si. lateral sepal, p. petals united to galea, /. basal part of labellum, n. nectary on upper part of its thickened extremity, cl. case of anther ending in front in spiral ribbons, d. attachment of disc at extremity of those ribbons, can. caudicle, c. anther. Iridaceae. PE. external and pi. internal perianth-segment, pt. perianth-tube, co. column of filaments, a. anther, si. stigmatic lip, n. scale covering nectar-cup. Moraea tristis. Fig. 133. Whole flower. Fig. 134. Staminal column and style with perianth removed. PLATE XXIII. Moraea trictispis. Fig. 135. Flower with external perianth-segments removed. Figs. 136 and 137. External perianth- segment seen from within and in longitu- dinal section. Moraea angusta. Fig. 138. Perianth removed. Figs. 139 and 140. External perianth-segment from within and in section. Moraea papilionacea. Fig. 141. Flower in longitudinal vertical section. Moraea tripetala. Fig. 142. Flower with one external perianth-segment and style-branch removed. Ferraria undulata . Fig. 143. Flower in median vertical section. Fig. 144. A style-papilla enlarged. Pa. papillae. A frican and Madagascar Flowering Plants . 40 1 Romulea rosea. Fig. 145. Flower in longitudinal mesial section. lip. hairs on petals, is. inner and os. outer spathes, HF. hairs on filaments. Galaxia graminea. Fig. 146. Flower in vertical section. Aristea spiralis. Fig. 147. Longitudinal mesial section of flower. Ixia graminifolia. Fig. 148. Longitudinal mesial section of flower. Ixia excisa. Fig. 149. Longitudinal mesial section of flower. Geissorhiza secunda. Fig. 1 50. Flower with part of perianth cut away. Melasphaerula graminea. Fig. 151. Flower seen obliquely from the side. Sparaxis grandijlora. Fig. 152. Flower in longitudinal mesial section, po. pollen-covered faces of anthers, a. entrance to honey. Babiana spathacea. Fig. 153. Flower in longitudinal mesial section, cr. up-turned edges of lower perianth-segments, the natural position is as in Fig. 154. Babiana plicata. Fig. 1 54. Flower in longitudinal mesial section : first or male condition. Fig- 155. Relative position of anthers and style -branches in second or female condition. Gladiolus pilosus. Fig. 156. Flower seen obliquely from in front. Figs. 157, 158, and 159. Successive positions relatively of anthers and style- branches. Gladiolus gracilis. Fig. 160. Flower in longitudinal section (male stage), natural position as in Fig. 154. Fig. 1 61. Second or female condition. Gladiolus injlatus. Fig. 162. Corolla from the side. Albuca major. Fig. 163. Internal perianth- segment from within, ip. incurved terminal part of inner perianth-segment. fx. basal pouching part of inner stamen, p\ groove formed by bending inwards of filaments,^ upper flat portion, a. anther, sti. stigma. Androcymbium leucanthum. Fig. 164. Flower half natural size. Fig. 165. Flower with floral leaves removed. Fig. 1 66. Perianth-segment with attached filament in longitudinal section, /. leaves (cut off), fl. dome-shaped floral leaves, c. pouch for honey secreted by n. nectary, a. anther. 402 Scott Elliot. — On the Fertilisation of South GENERIC INDEX. Abutilon, Fig. jo, p. 338. Adenandra, p. 340. Agathosma, p. 340. Albuca, Fig. 163, p. 392. Amphithalea, Figs. 31-34, p. 344. Androcymbium, Figs. 164-166, p. 393. Anemone, p. 334. Angraecum, Figs. 127-129 p. 378. Antholyza, p. 389. Arctotis, p. 358. Aristea (2 sp.), Fig. 147, p. 384. Aspalathus (3 sp.), Figs. 47-55, p. 345- Aster, p. 366. Asy stasia, p. 371. Babiana (2 sp.), Figs. 153-155; P- 3S7. Baeometra, p. 393. Belmontia, Fig. 99, p. 365. Berkheya, p. 359. Bidens, p. 357. Blaeria, p. 362. Borbonia, Figs. 35-37, p. 344. Brachystephanus, Fig. 112, p. 371. Brexia, Figs. 85, 86, p. 354. Camptocarpus, Fig. 98, p. 364. Canavalia, Figs. 70, 71, p. 350. Canthium, p. 355. Carica, Figs. 1, 2, p. 334. Cenia, p. 357. Chaenostoma, p. 368. Cineraria, p. 357. Clitoria, Fig. 69, p. 349. Colea, Figs. 109-m, p. 370. Commelina, p. 393. Cotyledon, p. 353. Craterostigma, p. 367. Crocus, p. 391. Crotalaria, Figs. 56-65, p. 346. Cryptostemma, p. 358. Cullumia, p. 359. Cyclopia, Figs. 11-16, p. 341. Cypella, p. 391. Dimorphotheca, p. 357. Diosma, p. 340. Diplopappus, p. 356. Dischisma, Fig. 114, p. 372. Disperis, Figs. 130-132, p. 379. Dolichos, Figs. 76-83, p. 352. Dombeya, p. 338. Erica (2 sp.), p. 361. Erythrina, p. 350. Euryops, p. 357. Ferraria, Figs. 143, 144, p. 382. Freesia, p. 386. Galaxia, Fig. 146, p. 383. Gazania, Fig. 90, p. 358. Geissorhiza Fig. 150, p. 385. Gladiolus (4sp.), Figs. 156-162, p. 3 88. Gomphocarpus, p. 364. Goodenia, p. 361. Gorteria, Fig. 89, p. 358. Gymnodiscus, Fig. 87 b, p. 357. Hesperantha, p. 384. Hibiscus, p. 338. Homeria (2 sp.), p. 382. Hydrocotyle, p. 355. Ilysanthes, Figs. 106-108, p. 369. Impatiens, p. 340. Indigofera, p. 348. Ipomoea (2 sp.), p. 366. Iris, p. 391. Ixia (3 sp.), Figs. 148, 149, p. 385. Kalancboe, p. 354. Kniphofia, p. 391. Ivraussia, p. 355. Lachenalia, p. 392. Lapeyrousia, p. 386. Lessertia, Figs. 66-68, p. 349. A frican and Madagascar Flowering Plants. 403 Leucadendron, Figs. 120, 121, p. 377. Liparia, Figs. 27-30, p. 343. Lobelia (2 sp.), p. 361. Lobostemon, Fig. 100, p. 366. Lotononis (2 sp.), Figs. 38-46, p. 345. Lycium, Fig. 101, p. 366. Manulea (2 sp.), Figs. 104, 105, p.368. Melasphaerula, Fig. 151, p. 386. Mesembryanthemum, Fig. 87 a , p. 354. Microcodon, p. 359. Montinia, p. 354. Moraea (6 sp.), Figs. 132-142, p. 380. Mundtia, p. 337. Muraltia (4 sp.), Figs. 7-9, p. 336. Myrsiphyllum, p. 391. Nemesia (2 sp.), Fig. 102, p. 367. Nepenthes, p. 376. Nymphea, p. 334. Ocirnum, p. 372. Oftia, Fig. 1 13, p. 371. Orchipeda, Figs. 90 c-94, p. 362. Osmitopsis, p. 356. Osteospermum, p. 358. Othonna, p. 357. Oxalis, p. 339. Pavetta, p. 355. Pelargonium (3 sp.), p. 339. Pentanisia, p. 355. Phaseolus (2 sp.), Figs. 72-75, p. 350. Phyllopodium, p. 368. Plectranthus (6 sp.), p. 373. Plectronia, p. 355. Podalyria (4 sp.), Figs. 17-26, p. 342. Polygala (2 sp.), Figs. 4-6, p. 335. Priestleya, p. 343. Psoralea (2 sp.), p. 347. Pterygodium, Figs. 123-126, p. 377. Quivisia, Fig. 84, p. 340. Rafnia, p. 345. Relhania, p. 356. Rhinacanthus, p. 371. Rhyncosia, p. 353. Rhytiglossa, p. 370. Romulea (2 sp.), Fig. 145, p. 383. Salvia (2 sp.), Fig. 118, p. 376. Scaevola, p. 360. Serruria, Fig. 122, p. 377. Sida, p. 338. Sparaxis, Fig. 152, p. 386. Stachys (3 sp.), Figs. 115-117, p- 375- Sutherlandia, p. 349. Syncolostemon (2 sp.), p. 372. Tachiadenus, p. 366. Teucrium, p. 376. Tripteris, Fig. 88, p. 357. Tritonia, p. 387. Ursinia, p. 358. Utricularia, p. 369. Viborgia, p. 345. Vigna (2 sp.), p. 351. Vinca, Figs. 95-97, p. 363. Viola, Fig. 3, p. 335. Virgilia, p. 353. Vitex, Fig. 119, p. 376. Wachendorfia, p. 391. Wahlenbergia (2 sp.), p. 359. Zaluzianskya, Fig. 103, p. 368. BIBLIOGRAPHY. Muller : ‘ Fertilisation of Flowers.’ London, 1883. 9 Arnaud :-Bull. d. 1. Soc. Bot. de France, Tome XXIV, 1877. 44 Beal : American Naturalist, Vol. XII, p. 308, 1878. 84 Bentham : Journ. Linn. Soc. Bot., Vol. X, p. 203, 1869. 153 Darwin, C. : Garden. Chron., pp. 552, 831, 1861. 162 • — - — , * On Various Contrivances by which British and Foreign Orchids are fertilised.’ London, 1877. 404 Scott Elliots — On the Fertilisation of South 169 Darwin, F. : Nature, Vol. IX, p. 189, 1874. 177 Delpino : Nuovo Giorn. Bot. Ital. II, 1870. — : Atti d. Soc. Ital. d. Sci. Nat. in Milano, Vols. XI and XII. 198 Denny : Florist and Pomologist, Jan. 1872 (not seen). 240 Farrer : Ann. and Mag. of Nat. Hist., Series 4, Vol. II, 1868. 242 — - : Nature, Vol. VI, pp. 478, 498. 1872. 323 Henslow : Journ. Linn. Soc. Bot., Vol. IX, 1867. 3 2 7 : Gard. Chron., Vol. V, p. 504, 1876. 346 Hildebrand: Bot. Zeit., Bd. XXIV, 1866. 352 : Bot. Zeit, Bd. XXV, 1867. 353 — : Bot. Zeit., Bd. XXVI, 1868. 356 — : Bot. Zeit, Bd. XXVII, 1869. 357 • Verh. der Leop. Carol. Acad. Dresden, Vol. XXXV, 1869. 360 ~ — — ■: Bot Zeit, Bd. XXVIII, 1870. 387 Kicks: Rev. de l’Hort. Belg., 1877 (not seen). 537 Moore: Journ. of Botany, New Series, Vol. V, 1876. 590 Muller, H. : Verh. des naturhist. Ver. d. preuss. Rheinl. u. Westf., 1878, 1879, an(l 1882. 592 — : Nature, Vol. XX, p. 147, 1879. 597 : American Naturalist, Vol. XIII, 1879. 609 : i Die Alpenblumen/ 8vo, Leipzig, 1881. 633 Ogle: Popular Science Review, Vol. IX, 1870. 702 Sprengel : Das entdeckte Geheimniss,’ &c. 4to, Berlin, 1793. 727 Trelease : American Naturalist, Vol. XIII, p. 427, 1879. 729 American Naturalist, Vol. XIII, p. 688, 1879. 742 Treviranus : Botan. Zeit., Bd. XXI, 1863. 751 Urban : Jahrbuch d. K. Botan. Gartens zu Berlin, Vol. I, 1881. 765 Weale : Journ. Linn. Soc. Bot, Vol. XIII, 1873. 775 Williams: Gard. Chron., Vol. XVI, p. 276, 1881. 781 Wilson, A. S. : Brit. Ass. Reports, p. 568, 1878. Macleod : Botanisch Jaarboek, Tweede Jaargang, Gent (Vuylsteke), 1890. 42 Battandier : Bull. Soc. Bot. de la France, Vol. XXX. 57 Breitenbach : Kosmos, 1885, Bd. I. 64 a Burgerstein : Ber. deut. Botan. Gesells., Bd. VII, 1889. 1 31 Focke : Kosmos, 1884, Bd. I (not seen). 151 Foerste : American Naturalist, Vol. XIX, 1885. 156 Francke : ‘ Einige Beitrage z. Kenntniss der Bestaubungseinricht.’ Inaug. Diss., Halle, 1883. 180 Hamilton: Proc. Linn. Soc. N. S. Wales, Vol. X, p. 154, 1885. 186 Haviland : See Hamilton, p. 237. 193 Heinricher : Sitz. der K. Akad. der Wissens. Wien, Bd. LXXXVII, 1883. 217 Hoffer: Kosmos, 1885, Bd. II. 244 Jordan : Flora, Bd. LXIX, 1886. 274 a Lange : Garden. Chronicle, Vol. XXVI, 1886, p. 339. 282 Licopoli : Rendic. Acad. sc. fis. e mat. Napoli, Vol. XXIV, 1885. 283 — — : Journ. de Micrographie, 1886, No. 2. 284 — — : Atti d. r. Acad, delle sci. fis. e mat., Series 2, Vol. II, 1888. 294 Loew : Ber. deut. Botan. Gesells., Bd. IV, 1886. 324 Ludwig: Biolog. Centralblatt, Bd. VI, 1887. Scott Elliot del. 'AtumiIs of Bolocny SCOTT ELLIOT.— ON FERTILISATION. Vol. V,PLXX1. Annals of Botany Vol. V, PL XXI. SCOTT ELLIOT.— ON FERTILISATION *5 Vol.V, PUXIJ University Press, Oxford. Voi. v7pi.mu University Press, Oxford. L/tnruzZs ofBotxxjiy SCOTT ELLIOT.— Scott Elliot del. Vol. V;PI.IX1II n. 'l FERTILISATION. 5 ,/tnr>MJJs of Botany YoL. V,PL.WII. SCOTT ELLIOT.— 0 FERTILISATION. African and Madagascar Flowering Plants. 405 337 Macleod: Botanisches Centralblatt, Bd. XXIII, 1885. 343 : Botan. Jaarboek, 1890, p. 143. 380 Meehan: Garden. Chron., Vol. XXII, 1884. 385 — : Proc. Acad. Nat. Sci., Philadelphia, 1886. 416 Muller, H. : Kosmos, Bd. VII, 1883. 419 F. : Ber. deut. Bot. Gesells., Bd. I, 1883. 435 Musset : Comptes Rendus Acad. Sci. Paris, Vol. CVIII, 1889. 476 Reid : Trans. Entomol. Kent. Soc., I, 1886 fnot seen). 516 Schulz : Bibliotheca Botanica, Heft 10, Cassel, 1881. 51 6a : „ „ „ 17, Cassel, 1890. 527 Stadler: c Beitrage znr. Kennt. Nectarien,’ Berlin, 1886. 546 Trelease : Proc. Boston Soc. Natur. Hist., Vol. XXI, 1882. 557 Urban : Jahrb. d. K. Botan. Gartens Berlin, Bd. II, 1883. 560 : Ber. d. deut. Bot. Gesells., Bd. Ill, 1885. 581 Watson : Gard. Chron., Vol. XXI, 1884, p. 87. 592 Wilson : Trans. Bot. Soc. Edinburgh, Vol. XVI, 1886. 593 : Trans. Bot. Soc. Edinburgh, Vol. XVII, 1887. : Botanisch Jaarboek, Derde Jaargang, 1891, p. 233. NOTES. PKOLONGED VITALITY OP THE SEEDS OP SEA- SHOEE PLANTS. — Although it has long been well known that the seeds of many sea-shore plants retain their germinating power after long immersion in sea-water, there are few exact observations on record. Dr. H. B. Guppy, who spent some months in the Keeling Islands (the scene of some of Darwin’s earliest work), and specially investigated the flora with reference to the germination and growth of seeds cast ashore by the waves, brought home seeds of many of the plants for further experiment. Some interesting results have been obtained. About the middle of last June he sent to Kew a germinat- ing seed of Thespesia populnea. This was collected fresh in the Keeling Islands in October, 1888, and kept dry until June 8th, 1890, when it was placed in sea-water, where it remained floating until June 8th, 1891. It was then subjected to conditions favourable to germ- ination, and in less than a fortnight it began to sprout, and it is now growing at Kew. On the 15th of July Dr. Guppy sent a germinating seed of Ipomoea grandijiora, collected in the same islands in No- vember, 1888, and subjected to the same treatment subsequently as the seed of Thespesia , with the only difference that it was five weeks before it germinated. Of course these tw^o instances merely confirm what was assumed before, namely, that the seeds of many of the plants found in remote islands must be able to endure long immersion in sea-water without injury ; yet they are none the less interesting. Both are ornamental plants — the Thespesia being a small tree and the Ipomoea a climber or trailer. Both have densely hairy seeds. The trigonous seeds of the latter are about a third of an inch long, and are furnished with an additional fringe of long hairs around the longer circumference, so that when they float, in still water at least, this fringe rests on the surface. Both have an exceedingly wide range of distribution, partly due, doubtless, to human agency on account of their ornamental character ; but also largely due to their capacity for colonisation from seeds cast ashore by the sea. Both occur on remote Notes . 407 uninhabited islands of the Pacific and Indian Oceans, whither it is highly improbable that they have been carried by man. W. BOTTING HEMSLEY, Kew. A BURMANNIA IN JAPAN.-— Through the kindness of Mr. Tokutaro Ito we have lately received at Kew specimens of a Bur- mannia , discovered by him in Japan, which, on comparison, proves to be B. nepalensis , Hook. f. ( Gonyanthes nepalensis , Miers). A few years ago Mr. Ford, Superintendent of the Hongkong Botanic Garden, collected the same species on the Lofau mountains, in the province of Kwangtung ; but it does not appear to have been found between there and India. It is however an exceedingly slender colourless plant two or three inches high, and might easily be overlooked. The Japanese habitat is Obi in the province of Hiogo, Kiusiu. W. BOTTING HEMSLEY, Kew. FLORA OF THE SOLOMON ISLANDS. — The Rev. R. B. Comins, who has spent some years in these islands, brought home a small but interesting collection of dried plants towards the end of last year. This collection is being worked out at Kew, and will form the subject of some notes in an early number of the Annals of Botany \ It contains several curious new plants, including a new genus of Scitamineae, and the very singular apocynaceous Lepinia taitensis , Decne., figured in the * Annales des Sciences Naturelles' in 1849. W. BOTTING HEMSLEY, Kew. ON RHYNCHOSIA? ANTENNULIFERA, /. G. Baker . In a note at the end of the enumeration of the genus Rhyne hosia in Oliver's ‘Flora of Tropical Africa,' vol. ii. p. 223, Mr. Baker described, under the above name, an imperfect specimen of a plant collected by Dr. Meller in Zambesi-land. Since then much better material has been received at Kew. Sir John Kirk appears to have been the first to collect it, though the specimens did not reach Kew until 1883, having formed part of a collection that was ‘lost' in a government warehouse at Southampton for nearly a quarter of a century! He collected it at Mungazi, in Zambesi-land, in 1859, and Dr. Meller collected it in 1861; both specimens wanting leaves and ripe fruit. In 1881, the Botanical Society of Edinburgh sent excellent specimens to Kew, collected by Mr. Buchanan in the Shiri F f 408 Notes. Highlands. More recently it has been collected in a leafless con- dition by a German traveller very much farther to the north, in the Uniamwesi country. A very marked peculiarity of the plant is that the bracts, bracteoles, and long narrow calyx-lobes, terminate in a club-shaped gland, and on this account Mr. Paul Taubert, of Berlin, has considered it should be classed as a new genus. Not having identified it with the plant described by Baker, Taubert first described and figured it under the name of Eminia eminens (Ber. der deutsch. Bot. Gesellschaft, ix. 1891, p. 28), and on being informed from Kew that it was the same as Rhynchosia! antennulifera , J. G. Baker, he altered the name to Eminia antennulifera (Bot. Centralblatt, xlv. 1891), following the rule of according priority to the first specific name given to the plant. As already mentioned, he had only a leafless specimen to deal with, and it was otherwise imperfect, as is clear from his description of the inflorescence. Whether Eminia can be regarded as a good genus it is not easy to decide without examining a large number of the plants most nearly allied ; but the gland -tipped calyx -segments seem to aflord a very slender character on which to found a genus, especially if we take into consideration the extreme variation in the calyx of the genus Rhynchosia, as usually limited. This, however, is a secondary matter. Buchanan's specimens afford complete material for a description, but it will be sufficient to supplement the previously published descriptions here : Radix grandis, carnosa ( fide Buchanan), caulibus pluripedalibus scandentibus liquescentibus interdum fere semipoll, diametro. Folia pinnatim trifoliolata, saepe longe petiolata, crassiuscula sed vix coriacea, utrinque sed praecipue subtus appresse sericeo-hirsuta vel strigillosa, cum petiolo usque ad 6 poll, longa, stipulis parvis oblongis ; foliola breviter petiolulata, late trilobata (usque 3 poll, longa lataque) lobis rotundatis simul minute apiculatis, lateralibus multo minoribus, foliolorum lateralium lobo interior interdum fere obsoleto, venis subtus saepe ferrugineis, stipellis subulatis ferrugineis. Flores fasciculato-racemosi, racemis usque sesquipedalem longis. In looking through the tropical African species of Rhynchosia in the Kew Herbarium, in connection with the foregoing, a second species having gland-tipped bracteoles and calyx -lobes was detected. This was collected by Dr. E. Holub in the Leshumo Valley, Zambesi, and Notes . 409 is quite distinct from R. antennulifera. But this second species rather weakens than strengthens Eminia as a genus, and it is proposed to treat it as a section of Rhynchosia here, Rhynchosia (§ Eminia) Holubii , HemsI. nov, spec. : foliis per anthesin persistentibus, foliolis oblongis sinuatis ; racemis folia vix superantibus ; calyce quam corolla dimidio breviore, laciniis 3 inferior!- bus saepius 2-3 glandulosis ; stylo per totam longitudinem glabro. Herba , ut videtur, perennis, caulibus . . . . ? Folia graciliter petiolata, pinnatim trifoliolata, coriacea, strigillosa, cum petiolo 3-5 poll, longa ; foliola breviter petiolulata, oblonga vel anguste ovato- oblonga, 2-3 poll, longa, lateralia paullo minora, sinuata vel obscure paucicrenata, utrinque obtusissima, simul apice minute apiculata, supra parce strigillosa, scabrida, venis elevatis grosse reticulatis, subtus argentea, dense strigillosa, venis primariis lateralibus utrinque circiter 5, stipellis obsoletis. Flores circiter 9 lineas longi, fasciculato- racemosi, brevissime pedicellati, racemis axillaribus folia subaequanti- bus calyceque argenteis strigilloso-hirsutis ; calyx sub-bilabiatus, alte inequaliter 4-fidus (i. e. laciniis 2 superioribus fere ad apicem con- natis), lacinia inferiore saepius apice 3-glandulosa, laciniis lateralibus saepius 2 -glandulosis, labio superiore saepius eglanduloso ; petala fere aequilonga, unguiculata, glabra, vexillo lato le viter emarginato ; stamina glabra ; ovarium subsessile, apice praesertim longissime setulosum, stylo longissimo breviter exserto glabro. Legumen ignotum. Apart from the great difference in foliage, and apparently in habit, this species differs in the relative length of corolla and calyx, and especially in the two upper calyx-lobes being connate nearly to the apex and eglandular, and in the three lower being furnished with two or three glands at the apex. W. BOTTING HEMSLEY, Kew. ON THE PRESENCE OF A DIASTATIC FERMENT IN GREEN LEAVES. — I have been led to re-investigate this subject in consequence of the statement made by Wortmann1 in a paper recently published, that green leaves contain no diastase or only such a minute quantity that it cannot be of any serious importance in the transformation of starch into sugar which takes place so actively in those organs. In contradiction of the results obtained by Baranetzky 2 1 Botanische Zeitung, 1890. 1 Die starkeumbildenden Fermente in den Pflanzen : Leipzig, 1878. F f 2 4io Notes . and of Brasse 1, which seem to prove the presence of diastase, Wort- mann finds that watery extracts of green leaves have no diastatic action, and concludes that the normal conversion of starch into sugar is effected in the living leaf by the direct action of the protoplasm. I am unable, within the limits of a note, to criticise Wortmann’s experiments in detail, or to give a full account of my own. In the way of criticism I would only point out that Wortmann’s method is open to serious objection : the mixing of a certain quantity of leaf- extract with a certain quantity of starch-solution, and then using the iodine-reaction as a means of determining the amount of chemical change effected, is not a method calculated to give definite results; for, as Wortmann himself admits, the colouring-matters and other foreign substances in the leaf-extract interfere with the colour-reactions with iodine. Again, it is disadvantageous to filter, as Wortmann did, the watery extract of the leaves before adding it to the starch-solution. I have found that the turbid extract, merely strained, is much more active than the clear extract obtained by filtration : probably Wortmann’s negative results were mainly due to this cause. There is one experiment upon which Wortmann lays so much stress that it calls for special notice. He finds that the starch will not disappear from the cells of a living leaf if the leaf be kept in an atmosphere of carbon dioxide; and from this he concludes that the transformation of starch into sugar must be a direct vital act of the protoplasm, dependent upon the supply of free oxygen. Assuming the correctness of the observation, a more simple and satisfactory explanation of it would be that, in the absence of free oxygen, the protoplasm is unable to secrete the necessary diastatic ferment. My experiments appear to establish the fact that a diastatic ferment is present in green leaves. The following description of a single typical experiment will give an idea of the methods adopted and of the nature of the re suits obtained : 500 grmes. of grass (with some Clover and Achillea intermixed), cut from a lawn, were well triturated in a mortar with 500 cc. distilled water : the mass was pressed through a strainer and a turbid slightly acid liquid, the leaf-extract, was obtained. In the afternoon, about four hours later (4.30 p.m.), the following mixtures were made in six jars, and were allowed to stand on the laboratory table till 6.45 a. m. the following morning, when they were all boiled at once ; they were 1 Comptes renclus, t. xcix, 1884. Notes . 411 then decolourised, and the presence of sugar and its amount in each was volumetrically determined by means of carefully prepared Fehling’s solution : Jar No. Nature of Mixture. Amt. of Sugar ( estd . as Dextrose'). per 100 ce. 1 — 50 cc. extract + 50 cc. starch-solution . . . -0793 grme. 2— 50 cc. extract ( boiled ) + „ ... .0450 „ 3— 50 cc. extract + 50 cc. „ + thymol . . -0740 „ 4 — „ „ + „ „ + boracic acid -5 grme. -0690 „ 5 - it „ + » distilled water . . . .0444 „ 6 — ,, starch-solution + ,, „ ,, . .. no trace. The starch-solution used was obtained by boiling *5 grme. of starch with 100 cc. of dist. water; the liquid was allowed to cool and settle in a closed vessel, and only the nearly clear supernatant por- tion was used. The activity of the ferment is represented by the difference between the amount of sugar in the leaf-extract to begin with, and the amount ultimately found in the mixture of leaf-extract and starch-solution : thus, from Nos. 2 and 5 it appears that the amount of sugar originally in the extract was about -045 per cent., so that the amount of sugar formed from the starch-solution by the ferment in No. 1 is about *034 per cent. It may be objected that this represents a very small amount of diastatic activity, so small indeed that it may be neglected as a factor in the almost wholesale conversion of starch into sugar which takes place in the living leaf ; but this objection is deprived of weight by the consideration that, though the amount of ferment which can be extracted from leaves at any given moment is so small, yet the ferment is doubtless being constantly secreted, so that the total amount secreted during a night, for instance, would suffice to effect the observed con- version of starch into sugar. In two cases ( Rheum hybridum , Daucus Caro/a) somewhat peculiar results were obtained. In the former, the mixture of leaf-extract and starch-solution was found to contain less sugar (-1587°/^) than the mixture of leaf-extract and distilled water (-2 7o2°/0), after standing for 24 hours: in the latter also the mixture contained less sugar - (-io527o) than the leaf-extract diluted to the same bulk (*1250°/^). It would appear that, in these cases, the added starch was not attacked at all : hence the question arises as to the explanation of these varying amounts of sugar. An explanation is suggested by the further observation, made as a control-experiment in the case of Daucus , that 412 Notes. an equivalent quantity of diluted leaf-extract which was boiled at the beginning of the experiment contained only about -o8 °/Q sugar. Since the unboiled leaf-extract, whether diluted with water or with starch- solution, contained more sugar than the boiled leaf-extract, it is clear that some amount of starch must have become converted into sugar ; and it is also clear that, since this increase of sugar is most marked in the leaf-extract to which no starch- solution had been added, it must be due to the conversion of starch already present in the cells of the leaf. The presence of added starch appears to interfere with the action of the ferment upon the leaf-starch. I have assured myself that the substance which reduces the Feh- ling’s solution is really a sugar; but it does not appear to be maltose, as might be expected, for it is not dextrorotatory though it seems to be fermentable. Further details are given in the paper which I am preparing to be read at the meeting of the British Association at Cardiff. S. H. VINES, Oxford. On Aggregations of Proteid in the cells of Euphorbia splendens. BY R. E. FRY, B.A. With Plate XXIV, HILE examining sections of the stem of Euphorbia splendens (using spirit-material) I observed in many of the cells, particularly in the parenchyma immediately surrounding the vascular bundles, certain spherical bodies, which refracted light strongly and in some cases had double contours, though they were not doubly refracting. They stained deeply with the following reagents : — - haematoxylin, Hanstein’s violet, eosin, Hoffmann’s blue. With iodine they were stained the yellowish brown colour characteristic of proteids. They were exceedingly insoluble, not being affected by saturated NaCl-solution, 5 per cent, potash, hydrochloric or acetic acids, or ether. These reactions suggested the presence of a coagulated proteid. This view was confirmed by the use of Millon’s reagent, and the xanthoproteic test, which gave the characteristic red and deep yellow colours. I also used a test described by Loew 1. It consists in precipitating the proteid by the action of a solution of potassium ferrocyanide and acetic acid, washing out these by treatment with 60 per cent, alcohol for half an hour and 1 Bot. Zeit. No. 18, May, 1884. [Annals of Botany, Vol. V. No. XX. November, 1891.] Gg 414 Fry —On Aggregations of Proteid in adding dilute ferric chloride. The proteid is then stained blue. This test confirmed the results already obtained. Thus the bodies were shown to consist of coagulated masses of proteid ; the coagulation being probably in part the result of the action of the alcohol. In the fresh state the proteid occurs in various forms : — (i) It may be distributed throughout the cell-contents either as a fluid or in finely divided granules. If cells containing this diffused proteid be treated with i per cent, ammonium carbonate for twenty-four hours the proteid crystallizes out. (f) A form common in young shoots is that shown in Fig. i a. These long crystalloids occur either singly in bundles or united to form sphaerocrystals. They are similar to those of Galtonia candicans 1 and Urtica urens 1 2. (3) The long rod-like crystalloids produced artificially by the action of ammonium carbonate on (1) also occur naturally. They are shown in Fig. 1 /3. They correspond to the forms found in Griffithsia neapolitana 3. (4) A form of crystalloid that is common in the epider- mis of the leaf is the common rhombohedral crystalloid which is found in the tuber of the Potato, the berries of Solanum americanum , and in Bertholletia excelsa. Like the crystalloids of the last-named plant, those of Eu- phorbia splendens are not doubly refracting. The crys- talloids of the potato-tuber, on the contrary, are doubly refracting. Fig. 1 y. Thus we see that this one species contains all the more remarkable forms of crystalloids that have been described as occurring elsewhere in widely different plants. But besides these there is a peculiar form. This is shown in Fig. 2, which represents a section of the stem in the fresh state mounted in water. There are really two forms here, (1) the loose aggregations 1 Leitgeb, Mitth. aus dem Bot. Inst, zu Graz, 1886. 2 Kallen, Flora, 1882, No. 5. 3 Klein, Pringsheim’s Jahrb. fiir wiss. Bot., vol. XIII. 4i5- the cells of Euphorbia splendens. of proteid granules shown at (c), and (2) the compact spheres (a) with strongly marked double contours ; these are highly refracting. Possibly (1) is only a stage in the formation of (2) . The granules showed Brownian movements and appeared to consist of globulin, as they were immediately dissolved with 10 per cent. NaCl-solution. The more aggregated spheres only became clearer in the centre, indicating possibly a globulin centre with a more insoluble shell. But the outer part also dissolved in dilute acids and was therefore probably composed of derived albumin. Such are the forms which the proteid contained in this species assumes under various conditions. I will next discuss their distribution with a view to showing its probable func- tion in the economy of the plant. Distribution in the stem. This is best seen by a reference to Fig. 3, which shows a cross-section of part of the stem. The cells containing proteid occur (1) in the inner layers of the cortex just outside the bast, (2) in the medullary rays (m), (3) in the pith (/) just within the wood. The inner parts of the cortex contain large numbers of latex-tubes whose thick walls were stained faintly blue when treated with Loew’s ferrocyanide-test, a fact which may be worth noticing by the way as it tends to support Wiesner’s hypothesis of the impregnation of the cell-wall by proteid. Although the cells surrounding the latex-tubes frequently contained proteid, there did not appear to be any such definite relation between the two as to suggest that the latex- tubes function as channels of distribution for the proteid. Scattered irregularly here and there are cells containing starch (.$*), which do not, however, form a regular starch- sheath. Cells containing proteid do not occur quite so con- stantly in the medullary rays and pith as in the inner layers of the cortex, but large quantities of proteid were frequently found in those parts. In quite young stems proteid was frequently observed in the peripheral layers of the cortex. G g 2 4i 6 Fry . — On Aggregations of Proteid in The cells of the growing-point and the pulvinus of young leaves are also full of proteid in a diffused form. Distribution in the leaves. The epidermis of the petiole and lamina of the leaves frequently contains crystalloids of the cubical form. In the mesophyll there is also a certain quantity of proteid, mostly diffuse or in irregular lumps. It is especially abun- dant in the cells of the palisade-parenchyma (/) lying over the small fibro-vascular bundles and tracheid-bundle-endings (Fig. 4). The ordinary elongated cells of the palisade-paren- chyma are here replaced by a number of small isodiametric cells with abundant cell-contents, consisting for the most part of irregularly formed masses of proteid. From the same figure it will be seen that the parenchy- matous sheath immediately surrounding the fibro-vascular bundles and tracheid-endings contains a number of spherical highly refracting bodies which at first sight seem to resemble the proteid masses of the stem ; their outlines, however, are more regular and they have a faint yellow tinge. Indeed they are not unlike oil-drops. They are not doubly refracting. They were insoluble in a mixture of absolute alcohol and ether, which showed they were not of an oily nature. They were also insoluble in 5 per cent, potash, and in saturated and 10 per cent, common salt solution. Dilute nitric and strong hydro- chloric acid dissolved them completely. With dilute hydro- chloric they became granular, less highly refracting, and less spherical. When treated with ammonium chromate they gave no colour, showing the absence of tannin. Nor did they stain with corallin-soda, alkanet or methylene-blue. With eosin, Hoffmann’s blue and Hanstein’s reagent they stained deeply. With iodine they gave a deep yellow colour. Such a behaviour towards reagents would lead one to suppose that they might be of a proteid nature, but all attempts to confirm this by positive methods failed. With Millon’s reagent they gave a dull brown, with the xanthoproteic test I sometimes thought I obtained a faint yellow, but it was 4i; the cells of Euphorbia splendens. exceedingly difficult to apply, as they were dissolved in any but very weak nitric acid. With Loew’s ferrocyanide-test I sometimes obtained a faint blue, very different to the deep clear blue given by the proteid masses of the stem. Perhaps the best hypothesis is to consider them as bodies very closely allied to proteid, but not answering to all the tests for it. One might perhaps compare with them mucin, which gives the characteristic proteid-reaction with the xanthoproteic test, but not with any other. Moreover since it is probable that nitrogenous food-material travels from one part of the plant to another in the form of glycines, we may provisionally regard these bodies as intermediate between the true pro- teids which constitute the nitrogenous reserve material, and the glycines which diffuse from cell to cell. This view is supported by the fact that they disappear in a starving leaf. The question naturally arises, What is the value of these proteid masses in the economy of the plant ? With a view to answering this I made several observations. The very nature of the substance makes it probable that they are of im- portance to the plant as reserve material, and all my observa- tions tended to support this view. I took some quite small cuttings from a plant of Euphorbia splendens and grew them with a strong bottom heat, so that they might form roots rapidly. The plants were then cut in half longitudinally and a thin slice treated with hot Millon’s reagent. The distribu- tion of proteid could then be observed macroscopically by the distribution of the red colour. The base of the stem was much redder than the apex, owing to the quantity of proteid required there for the growing roots : whereas under normal conditions the apex, where cell-division is going on, is more plentifully supplied than any other part of the stem. I then applied a macroscopic proteid-test to the leaves. They were treated thus : — decolourized with alcohol, the cuticle carefully removed with strong and hot hydrochloric acid, and Loew’s ferrocyanide-test applied. This treatment was applied to two similar leaves of two similar cuttings, 4i 8 Fry. — On Aggregations of Proteid, &c. one of which had been kept in the dark for some days, the other in the light. As was to be expected, the etiolated leaf had used up much of its reserve proteid. I next investigated the effect of light on the formation of proteid by imitating exactly Sachs’ macroscopic starch-test, except that I substituted Loew’s ferrocyanide-test for treat- ment with iodine. In no case did I find that light had any effect on the quantity of proteid formed. These observations then tend to show that the proteid is used as reserve nitrogenous material, answering to starch among carbohydrates. It is noteworthy that the distribution in the stem of the cells containing proteid is similar to that of the irregular starch-sheath, cells containing proteid al- ternating with cells containing starch. In all physiological respects these proteid-containing cells resemble the ‘ Eiweiss- schlauche ’ of the Cruciferae described by Heinricher 1, as also in many respects in their distribution. I may mention that I examined many species of the Euphorbiaceae and many latex-containing plants of other families, belonging to the genera Manihot , Hoya, Hevea , Oxypetalum , Ficus , Sapium , Pharmacosycea , without finding any such aggregation of reserve proteids. I ought to add that Euphorbia Bojeriy by some considered as a variety of E. splendensy is exactly similar to it as regards its accumulations of proteid. In conclusion I must thank Professor Vines and Mr. Gardiner for their helpful suggestions and advice in this investigation. 1 E. Heinricher, Eiweissschlauche d. Cruciferen, Mitth. aus dem Bot. Inst, zu Graz, 1 886. Jbincds of. Bofxmy Vol. V.Pl.XXIV. Fry del. University Press, Oxford. FRY.— ON PROTE1D IN EUPHORBIA SPLE N DENS. *0n the Fructification of Bennettites gibson- ianus, Carr. BY H. GRAF ZU SOLMS-LAUBACH. With Plates XXV and XXVI. E have long been acquainted with numerous stems which V V are found in the Jurassic and Lower Chalk of Eng- land ; and which, wrapped all round in a close armour of leaf- bases, are, on account of the similarity of habit, usually classed with Cycadeae. It was only gradually that it became known that many of these stems, especially when silicified, show the internal structure in the most beautiful manner. Buckland2 was the first who established this fact in the case of the objects known as ‘ birds’ -nests ’ from the dirt-beds of the Island of Portland. He also succeeded, with the help of R. Brown, in giving a satisfactory explanation of the most important features in the internal structure of the stem and of the panoply of leaf- bases. Further investigations in the same direction were made 1 The Editors have thought that this important paper, based as it is entirely on English material, should have a place in the pages of the Annals. They desire to express their thanks to Graf Solms for the permission to translate his paper ; and to Mr. H. E. Garnsey, of Magdalen College, Oxford, for the trouble he has taken in preparing this careful translation. The paper was originally published in the Botanische Zeitung for 1890. 2 Buckland, ‘ On the Cycadoideae, a family of fossil plants found in the Oolite quarries of the Isle of Portland/ Trans. Geol. Soe. of London, ser. 2, vol. ii. (1829), p. 395. [Annals of Botany, Vol. V. No. XX. November, 1891.] 420 Solms-Laubach . — On the Fructification by G. A. Mantell1 with material obtained from the Isle of Wight. He says of a stem which he had picked up as a pebble on the shore of Brook Bay : * This fragment is highly interesting, for the calcareo-silicious earth, of which the stem now consists, is of a finer texture than in any of the Tilgate Forest specimens, and transverse sections display under the microscope more satisfactory indications of the organisation of the original. Without many figures and more lengthened descriptions than our space will admit of, the peculiarities of structure exhibited in these slices could not be demonstrated ; it must therefore suffice to state that the organisation, so far as it can be determined, shows a near approach to that of the Cycadeae.5 I believe that I recognise this specimen in a stem at present in the Geological Department of the British Museum, which has been cut through and marked on the upper surface with the word ‘ Brook ’ written in ink. I am not perfectly certain on this point, because there are several fragments of the same mineral substance lying close to it and known to have come from Mantell ; and because this particular specimen, strange to say, does not bear the number which indicates its place in Mantell’s collection. Mantell also states 2 that Mr. Saxby, of Bonchurch, in the Isle of Wight, had lent him the section of a Clathr arici-s tem showing structure, ‘ in which the bundles of vascular tissue in the petioles appear to be made up of spiral vessels.’ I have not been able to ascertain where this preparation is preserved. Almost at the same time Corda3 published a figure and description of the structure of the leaf-bases of his Zamites Bucklandi which belongs to this group ; he suspects that the specimen in the imperial collection at Vienna came from England. It may seem strange that, under such circumstances, no further contribution to our knowledge of the anatomical struc- 1 Mantell, ‘The Medals of Creation,’ ed. 2, vol. ii. p. 162, and ‘Geological Excursion round the Isle of Wight,’ p. 215. London, 1854. 2 Mantell, ‘The Medals of Creation,’ ed. 2, vol. ii. p. 162. 3 Corda, ‘ Beitrage zur Flora der Vorwelt,’ p. 38, t. 17. Prag, 1845. 42 f of Bennettites gibsonianus \ Carr. ture of the stems in question made its appearance before the year 1868, when Carruthers’ excellent account of them was published \ and that nothing has since been added respecting them with the exception of Camel’s description of his Raumeria cocchiana 2, though a rich store of material has been lying waiting for examination in various museums. Massalongo and Scarabelli. indeed, began the study of the specimens found in Upper Italy, and a number of drawings had been completed when the work was interrupted by the death of Massalongo ; it has been resumed by Capellini and myself, and the Marchese Scarabelli, of Imola, has in the kindest manner handed over to us the material and also the figures which have been already executed. But the neglect of this very interesting subject, even after attention had been drawn to it by Carruthers, becomes in- telligible when we learn to know the peculiar difficulties with which its study is surrounded. The specimens are rare, often unique, the ornament and pride of the different museums ; they are scattered over the whole of Europe, and have recently been heard of from America also, and unfortunately it is not always easy to obtain leave for the close examination which necessarily presupposes the making sections through them. Another specially embarrassing circumstance is the size of the specimens, which in some cases is astonishing, and makes it difficult to transport them, and extremely laborious and costly to cut them. It is only in a few workshops that it is possible to deal with such huge and at the same time hard and intractable masses of stone. The size is a very great and special hindrance in the way of obtaining thin slices ; and this was still more the case when Carruthers undertook his investiga- tions than it is at the present day ; but notwithstanding this difficulty he has explained the structure of the stems and leaf- 1 Carruthers, W., ‘ On fossil Cycadean stems from the secondary rocks of Britain/ Trans. Linn. Soc. vol. 26 (1870), p. 675. See also the summary in F. Dixon, ‘ The Geology of Sussex/ New Edition, revised by Rupert Jones, p. 277. Brighton, 1878. ' ' 2 Caruel, T., * Osservazioni sul genere di Cicadacee fossili Raumeriae, descr. di una specie nova,’ Bolletino del Reale Com. Geol. d’ltalia, no. 7, 8 (1870), p. 181. 422 Solms-Laubach. — On the Fructification bases, and that of the fructifications squeezed in between the bases of the leaves, in so masterly a manner from his numer- ous preparations, that at present I have chiefly only to confirm his results, though, as might be expected, a fresh examination may be found to throw further light on some questions of detail. Carruthers’ investigations embraced a large number of stems which had been discovered in the course of time chiefly in the south of England, and their result was to show that in all cases alike there were certain anatomical characters which in- dicate an essential difference from recent Cycadeae. The leaf- trace was found in every case to be formed of a single strand, which, separating by repeated division into numerous branches before it issues from the leaf, runs perpendicularly downwards through the cortex to enter the ring of wood ; in its lower portion it contributes largely for a certain distance to the secondary growth of the wood. There is no sign of the arching of the leaf-traces to form a girdle, such as we see in our living forms, and on this point I may venture to speak quite decidedly after repeated and most careful exami- nation of many specimens. The somewhat feebly developed hollow cylinder of the secondary growth separates normally into a ring of bast and a ring of wood ; it is divided by rather broad intervals, filled with parenchyma, into segments of unequal size. The tangential section which Carruthers had before him only in the case of his Bennettites saxbyanus , and which I find to have exactly the same structure in one of the Italian stems, shows a broadish rhomboid gap in the wood and bast over each of the emerging strands. It is these gaps filled with parenchyma, which cause the interruptions in the woody ring on the transverse section. The entire cylinder of wood and bast thus becomes a trellis-work, with spindle- shaped meshes, and consequently presents a very striking though superficial resemblance to the vascular bundle-system of the stems of Ferns, as Carruthers himself says on page 696 : 5 The analogy between these fossil stems and the caudex of a tree-fern is very remarkable.’ Closer examination will doubt- of Bennettites gibsonianus, Carr . 423 less disclose a greater affinity with the course of the vascular bundles in many Coniferae 1. The structure of the bundles and of the secondary wood and bast must be further investi- gated, but this much is certain, that it shows great similarity to the same structure in recent Cycadeae. In Bennettites , as in Cycadeae, pith and cortex are permeated by more or less numerous gum-passages. The pith of B . peachianus , Carr., from the Jurassic of Sutherland in the north of Scotland, shows, besides these passages, peculiar irregular rings which have not yet been fully investigated 2. Caruel 3 found some- thing of the same kind in his Raumeria cocchianay and of this I have now at my disposal the material necessary for examina- tion, through the kindness of Professor d’ Ancona, of Florence. I have been able to determine that we are here dealing with periderms, of which a fuller account will be given in another place. I hope before long to be able to say whether this is the case in Bennettites peachianus also ; the other stems which have been examined hitherto show nothing of the kind. These stems, like those of recent Cycadeae, are inclosed in an unbroken armour of leaf-bases, the internal structure of which has been elucidated by Carruthers and shows no peculiar features. Each leaf-base is transversely rhombic in cross-section ; in its parenchyma lie numerous bundles which together form a rhomboid figure parallel to the contour of the section, except on the upper side where the two limbs bend downwards and inwards. The epidermis bears a large number of hairs, like the ramenta of Ferns, composed of one or more layers of tissue, and so close together as to form a regular felt which completely fills the fissures between the several leaf-bases. The tissue of the leaf-bases had very often rotted away before petrifaction, and only the epidermal layers and the masses of hair between them were preserved. In such 1 See on this point Geyler, ‘ Ueber den Gefassbiindelverlauf in den Laubblatt- regionen der Coniferen,’ Pringsheim’s Jahrb. vi, tt. iv-ix ; and Bertrand and Renault, ‘ Recherches sur les Poroxylons,’ pp. 254-256. 2 See Carruthers, loc. cit, pi. 62. 3 See Caruel, as cited above. 424 Solms-L cutback —On the Fructification cases the outer surface shows a network of projecting ridges separating deep rhomboid cavities from one another. Cla- ihropodium foratum > Sap.1, is a good example of this state of preservation. But the leaf-armour, viewed from without, shows other unevennesses of surface in varying numbers and irregular dis- tribution, having a wh oiled appearance. Where these are well preserved, they are seen to be the transverse fractures of smaller leaves arranged round a centre of their own 2. They are leafy lateral branches which have forced their way through between the leaf-bases, considerably altering their shape, and which terminate in inflorescences or fructifications of very peculiar construction. These fructifications are at present known only in one species, Bennettites gibsonianus , Carr., in which their preservation is evidently due to the shortness of the axis, which prevents the spadix, as the structure may be termed, from rising above the surface of the leaf-bases. In all the other forms as yet described they pro- jected above the surface ; consequently the upper free portion has disappeared, and the middle of the transverse fracture is occupied by the transverse section of the axis. It is on the sum total of these characters that Carruthers has founded his group Bennettiteae, which he would have us regard as a subdivision of Cycadeae. But his own account of the structure of the fructification is sufficient to show that we are dealing here with a tribe of plants quite distinct from Cycadeae ; they may perhaps be coordinated with Cycadeae, but they certainly cannot be subordinated to them. Judging by the vegetative characters only, which recur in the same characteristic manner in countless stems, the nature of the fructification being known only in one species, Bennettites gibsonianus , we arrive at the surprising result that all the Jurassic and Neocomian stems which are termed Cycas- stems, so far as anything is known of their structure, belong to Bennettiteae, and that not a single one of them has been 1 See Paleontologie Frar^aise, terrain jurassique, vol. II, tab. 54. 2 See Carruthers, loc. cit., pi. 58, fig. 3. of Bennettites gibsonianus , Carr. 425 proved to be a genuine stem of Cycadeae. This further shows how precarious is the identification of fossil remains when it rests on superficial characters only. It was observed as early as 1851 by R. Brown1 that while the transverse section of all stems from the dirt-beds of the Island of Portland is circular, that of the stems from the Isle of Wight is distinctly elliptical. This difference is seen most plainly in the pith and ring of wood, and can hardly be attributed to subsequent compression. Carruthers has employed it to dis- tinguish his Bennettiteae into two genera ; Bennettites , Carr., containing the specimens with an elliptical transverse section ; and Cycadoidea , Buckl., in which the section of the stem is circular. I do not believe that this distinction will be main- tained, for among the specimens found in Italy and preserved in the Museums of Bologna and Imola, we find, besides the two types above-mentioned, others which are almost circular, and show only a very slight compression. I should therefore rather confine the name Bennettites to the species in which we know the characters of the fructification, that is to B. gib- sonianus, Carr. Among the Italian specimens there will perhaps be found some forms resembling B. gibsonianus , and requiring to be placed with it ; all the rest, which have only the basal portion of the fruiting shoot, may for the present be properly included under the name Cycadoidea , Buckl., whether their transverse section be round or elliptical. At the same time I do not propose to carry out this nomenclature, which would have been suitable enough in the beginning, but now, whilst we are still awaiting the final determination of all the facts of the case, would merely have the effect of increasing the synonymy, which is already sufficiently difficult. Carruthers’ account of the structure of the fructification of his Bennettites gibsonianus has often been misunderstood. It is really a very apt description of the fossil, but it is so concise that to understand it thoroughly requires very careful study and constant comparison of the figures. There are also some obscure points here and there which the author could not at 1 See Carruthers, loc. cit., p. 694. 426 Solms-L cutback. — On the Fructification the time clear up ; to do this would have required such an exactly transverse orientation of the slices as could not be obtained thirty years ago without difficulty and great waste of material. If I have contributed anything to the explana- tion of some of these points, as I think that I have, it is entirely due to the great liberality of Sir J. D. Hooker and Mr. Thiselton-Dyer in entrusting me with a portion of the precious material for the preparation of new slices, and of Carruthers himself in affording me repeated opportunities of examining the specimen preserved in the British Museum, and the preparations on which his work is founded. And if the present paper is occupied exclusively with the inflo- rescences of Bennettites gibsonianus , Carr., it is because my chief object is, by a detailed discussion of the characters disclosed in these fructifications, to obtain a foundation for the examination which I hope in time to make of the other forms. The material employed in the study of Bennettites gibso- nianus was obtained from a single large block, found in 1856 or 1857 by Thomas Field Gibson, in Luccomb Chine, at Bon- church, in the Isle of Wight, the history of which appears in the memorandum given below. It is true that Carruthers1 says that waterworn fragments of this species and of B. saxby- anus have been mistaken for portions of Bucklandia anomala by Mantell in his ‘Medals of Creation2,’ and that Fig. 57 in that work gives a very good woodcut of these fragments, & c. But after examination of these specimens, which are in the Geological Department of the British Museum, I am not satisfied that they really belong to B. gibsonianus . Of one of them, to which Mantell’s statements respecting the internal structure probably apply, I have spoken above; the others bear the numbers from Mantell’s collection, I. 38361 and 38363. No. I. 38361 is labelled gibsonianus , No. 38363 sax- by anus, in Carruthers’ own handwriting. Lastly, No. 38360, of which Mantell gives a separate figure, is also named B. gib- sonianus by Carruthers. All these fragments are specimens 1 See Carruthers, loc. cit., p. 700. 2 See vol. i. p. 163. of Bennettites gibsonianus, Carr. 427 of Bennettiteae, but they have no fructifications, and show only the basal transverse sections of the lateral spadices. I shall have to return to them in another place. With regard to the specimen known to be the original block of Bennettites gibsonianus , we have the following memo- randum, which was communicated to Carruthers by a member of the family of the discoverer, and which I was permitted to copy in the British Museum. It runs thus : ‘ This fossil plant was found by Thomas Field Gibson, Esq., in the Lower Green- sand at Luccomb Chine, Isle of Wight, in the year 1856 or 1857. In the spring of 1858 it was taken to Mr. Yates’ house at Highgate, where it was examined by Dr. Hooker and Mr. Morris, Professor of Geology at University College. They split it open, and found oval pods containing little seeds arranged regularly round near the edge. Each pod was about an inch and a half long. The best pieces containing the most perfect pods were kept by Mr. Gibson and Dr. Hooker, but this piece is much larger than the other part which was broken up, being about two-thirds of the original lump. I believe a similar specimen was found by Dr. Leeson, of Bonchurch.’ It appears, therefore, that the original block was broken in two with a hammer, and was thus split into two unequal halves, and beside these into a large number of smaller frag- ments. This explains why the two main pieces do not fit into one another in their present state. Hooker took the smaller (upper) main piece, and it is now in the Museum at Kew; the larger (under) main piece was made over by Gibson’s family to the Botanical Department of the British Museum. Hooker appears to have used some of the smaller fragments for the preparation of slices ; others were kept by Morris, from whose hands they passed into the private possession of Carruthers. I gather this from the fact that Carruthers has a fragment which still bears Morris’ label written with his own hand. Thus the material of Bennettites gibsonianus consists in its present state of the following pieces : — 1. Of the large and fine block in the Geological Department 428 Solms-Lcmbach . — On the Fructification of the British Museum. This block is twenty centimetres in height, twenty-seven centimetres broad in the longer axis of the elliptical transverse section, and eighteen centimetres and a half in the short axis of the same. It is the lower portion of the original block ; it becomes gradually smaller below, and terminates in a roundish projection. Externally it is angular and has sharp edges ; on the fresh surface of the frac- ture its colour is a dark chocolate brown, everywhere else it is covered with a yellowish brown ochreous crust. It shows no sign whatever of having been worn and smoothed by the action of the sea. The panoply of leaf-bases has been preserved all round. Two polished section-surfaces are seen in the rough block where portions of the margin have been cut off. The first of these has a tangential direction, passing transversely through the leaf-armour and the inclosed fructifications. The second shows the transverse section of the stem, and cuts longitudinally through the leaf-bases and fructifications. The petrifaction of the specimen is very perfect ; the material, as was said above, is tricalcium phosphate ; but there are gaps here and there which are usually filled with clay-stone or with crusts of iron oxide. Unfortunately the examination of many places, especially in the fructifications, is greatly obstructed by the presence in large quantities of opaque pyrites distributed throughout the entire block. 2. Of the upper and much smaller fragment of the original block, which now belongs to the Museum at Kew. This is less perfect than the piece in the British Museum ; a portion of the leaf-armour has disappeared on one side ; the outer surface even cuts off here and there a corner of the ring of wood and of the pith. The surface of one fracture has been cut smooth to obtain a polished transverse section of the stem. Part of the marginal portion thus set free has al- ready been used to make slices; the remainder, inclosing a fructification, has supplied the chief material for my new preparations. 3. Of a few small fragments in Carruthers’ possession, which came from Morris as the label on one of them shows. This of Bennettites gihsonianus , Carr. 429 fragment supplies an instructive fracture, which passes obliquely through a fructification. 4. Of a large series of slices, the material employed in Car- ruthers’ investigation, partly supplied by Hooker. These are sections in various directions through the fructifications. From the character of the stone and the structure I am satisfied that a slice, without a label, showing the transverse section of pith and woody cylinder, is one of this series. 5. Lastly, of the slices recently taken by myself from the fragment at Kew ; the chief of these are preserved at Kew ; a few duplicates have remained in my posses- sion. Note. In presence of the fact that so many stems of Bennettiteae have been found only in secondary places of deposit, it is very necessary to determine with all possible exactness the place of origin of all important specimens. I therefore visited Luccomb Chine in August 1889. The chine is a deep ravine entirely in the Lower Greensand. The lowermost bed of the formation on the sea-shore is rather less deeply cut into than the beds above it, and forms a nearly vertical wall from two to three metres high, of dark colour and sandy character. It is full of green grains of glauconite and small bits of iron pyrites, the iron giving rise to an ochreous coating on the surface in moist spots, and it contains an unusual quantity of small fragments of coal which deserve closer examination, though it would be necessary for this purpose to obtain unweathered material from within the bed. It also contains concretions like those of the Loess, which weather out and then lie on the sand of the shore among the fragments of flint ; comparison of the products of weathering with the bed leaves no doubt that the concretions come from the bed. If we break up the concretions we usually find at the centre of them a fragment of coniferous wood in good preservation, and sometimes covered with only a thin crust of stone. The wood is of a grey colour as long as it is quite fresh, but it passes into chocolate-brown as soon as it begins to weather. The material of petrifaction is calcium carbonate and tricalcium phosphate. The original block of Bennettites gihsonianus found at the same spot greatly resembles these concretions, and the rock adhering to it here and there has the same composition, but its outer surface is coloured ochre-brown all over, in consequence probably of being rich H h 430 Solms-Laubach. — On the Fructification in iron oxide and pyrites, and of having lain exposed a long time since it weathered out. All the facts show beyond doubt that it really comes from the Lower Greensand. A further proof is that in the argilla- ceous coating of the microscopical preparations in the British Museum I found a Foraminifer resembling a Rotalia , and this points to the marine character of the deposit containing the stem. I made enquiries after the Cycadean stem mentioned in the memorandum above as in the possession of Dr. Leeson, of Bonchurch, and purchased it ; it was found on a heap of stones on the land of the discoverer, now de- ceased. It is in fact what it appears to be, a second specimen of Bennettites gibsonianus ; its further examination must wait some future opportunity. The fruit-bearing lateral spadices of Bennettites gibsonianus are, according to Carruthers, of axillary origin, as had been already stated by R. Brown. But they do not by any means occur in every leaf-axil ; on the contrary, the majority of leaf- axils are in most cases empty. I would remark, however, that this view is very natural, and is indeed highly probable, but that we can hardly hope to give a decisive answer to the question. A short time since we were still in ignorance as to the mode of origin of the flowers in living Cycads. The position of the fructifications in Bennettiteae, as far as I can judge from the slices at my command, follows no fixed rule ; in some cases they emerge singly from between the leaf-bases which cover the stem ; in others they appear in groups, and are sometimes so crowded together as to be in close contact with one another. I also observed, when cutting a fragment into transverse slices, that the spadices are not all of the same length ; and that in the lower sections new ones, completely covered by the leaf- bases which close over them, were exposed between those previously observed. On comparing these preparations, I could not resist the impression that the new spadices were lateral branches of those which projected further from the axis. If this is the case, we should occasionally find fascicled systems of fertile axes emerging in a body and in close con- tiguity with one another, or thrusting their shoots singly into the interstices between the leaf-bases of the armour. But of Bennettites gibsonianus , Carr. 431 distinct proof of this cannot be obtained without an unlimited supply of material for making series of slices. The leaf-bases between the spadices are usually much out of shape, and the transverse section is irregular and distorted ; this makes it impossible, as a rule, to determine the precise relative position of the two kinds of organs. Where the spadices occur singly, they are indeed sometimes exactly over a leaf-base ; in other cases again they are thrust quite to one side. Displacements from pressure within the closed layer of contiguous organs would necessarily cause the disappearance of any positional arrangements which may have originally prevailed. But if the material at our disposal does not suffice to determine that the shoots in Bennettiteae were axillary, there is on the other hand nothing to show that they were terminal as in living Cycads, and that the stem which bears them was a sympo- dium. In no transverse section which we possess of any stem of Bennettiteae do we find even a trace of the bundle-system running into the pith, which is so characteristic of the flower- bearing termination of the axis in Cycadeae ; and where such shoots are so abundant as in the armour of Bennettites gibsonianus and other stems, it would be very strange if no section had ever hit upon a system of the kind. Each of the shoots terminating in spadices is composed of a large number of abbreviated internodes, and bears spirally disposed lanceolate acuminate cataphyllary leaves, biconvex in transverse section with two sharp edges. This is shown by Carruthers in figure 3 of plate 58 which gives the transverse section, and in figure 5 which is the oblique longitudinal section ; but the latter figure is not so clear as it would have been if the section had been truly median. The transverse section gives the axis of the shoot surrounded by its leaves, which are closely packed with no gaps, but with only narrow layers of the characteristic ramenta between them. There is an indication of the parastichies in the figure first cited. That these leaves are lanceolate and have no terminal lamina can be known for certain only where their surface, or the mould of it, is laid bare by the fracture. Here we can see both their H h 2 4 3 2 Solms-Lauback. — On the Fructification form and the median keel which gradually slopes towards the margins and projects on both surfaces, and gives the transverse section its characteristic shape. The block in the Museum at Kew may be specially mentioned as having a fine fracture of this kind, though the like may be seen also in other stems of Bennettiteae when the whole of the fruit-bearing shoot has decayed away or been broken off from the scale-armour, leaving only the basal internodes behind. The resulting funnel-shaped cavity is then lined with the narrowly lanceolate leaves. The reader is referred for this state of preservation to Carruthers’ figure of his Mantellia inclusa h The con- ditions here described are to be seen very distinctly in the original specimen of Bennettites maximus , Carr., in the Jermyn Street Museum in London. The cataphyllary leaves are similar in their internal structure to the leaf-bases of the armour of the stem. Here their fundamental parenchyma consists in all cases, not of thin-walled, but of stout cells thickened after the manner of scalariform tracheides, and incloses many broad cylindrical gum-receptacles which are much elongated longitudinally and contain a copious brown matter. One important difference is that each leaf has only three vascular bundles of delicate herbaceous texture and with a roundish transverse section ; the tissue is usually very badly preserved, and frequently shows nothing but a succession of empty spaces. The distinct epidermis is formed of one layer of very small cells. I have searched in vain for stomata in every slice. The section of one of these leaves given by Carruthers 2 is very true to nature, only the vascular bundles are not shown having been probably overlooked by the draughtsman ; there must have been one visible on the portion of the section represented in the figure. The peculiar paleaceous hairs (ramenta) of the leaf-bases of the stem are found, as has been already said, on the cataphyllary leaves, but they are fewer and smaller and very thin, and form intermediate layers which disappear in places 1 Carruthers, loc. cit, pi. 63 ,fig. 3. 3 Carruthers, loc. cit., pi. 60, fig. 6. 433 of Bennettites gibsonianus , Carr . altogether. These hairs are so very peculiar and differ so greatly from the simple unicellular twisted bristles which take their place in Cycas and Dioon , that we may devote a few words to them. They are leaf-like and resemble the ramenta of Ferns; radial longitudinal sections show that they possess considerable length, and are folded repeatedly be- tween and with one another in relation to the space which they have to occupy. Owing to these flexures and folds, we never see them in their full extension in surface-sections ; and for the same reason I have never been able to form a clear idea of the nature of their margin, and still less, of course, of their general figure. They are spindle-shaped in trans- verse section, and have a sharp edge to the margin on both sides. They are usually composed of a single layer of cells, but not unfrequently of two layers lying one on the other ; and in the middle they may contain as many as three layers, but at the margin there is never more than one layer. All their cell-walls appear to have been strongly thickened, and are broad, homogeneous, and of a dark brown colour ; in many cases indeed the secondary thickening-masses can be distinguished from the evident and lighter coloured middle lamella. The appearance of the transverse section of the hairs is admirably represented by Carruthers and also in Corda’s figures which belong to Zamites Bucklandi , and were incorrectly explained by this author, who took them for the macerated remains of the cataphyllary leaves between the leaf-bases. Tangential preparations show us the shape of the cells, which are elongate-tubular, with oblique ends thrust in between one another. Nathorst1 2 has suggested that the fructifications of Ben- nettites gibsonianus may have been parasitic on the stem of Cycads, and has attempted a comparison of them with the genus Lophophytum. If any further argument against this view were still wanting, to which the author of it himself no 1 Carruthers, loc. cit., pi. 60, figs. 7 and 11. 2 Nathorst, ‘ Nagra anmarkningar om Williamsonia , Carr./ Ofversight af Kongl. Vetenskaps. Akad. Forhandlingar. 1880, No. 9. 434 Solms-L aubach. — On the Fructification longer adheres, it would be found in the structure of the axis of the cone. Carruthers has told us that in the species of his genus Mantellia (the Cycadoidea of Buckland) the lateral axes show the structure of Cycadeae. His words are 1 : ‘ and show there a woody cylinder agreeing in structure with the principal axis of the plant.’ He had before him no transverse slice of the fertile shoot of Bennettites gibsonianus suitable for determining this point. It could be seen from those pre- pared by myself that the axis, which had lost its shape owing to the pressure of the surrounding leaf-bases and become very irregular, has a woody cylinder which is thin indeed and weak, but in all other respects is like that of the stem and follows the irregularities of the transverse section ; it can therefore only have reached its ultimate development after the distortion was complete. The transverse sections of numerous leaf-traces are visible on the outer surface in the cortex which, like the pith, consists of thin-walled parenchyma with many gum-passages. Of the seminiferous spadix which terminates the lateral shoot, and is enveloped in its leaves, Carruthers 2 says : c The branch terminates in a fleshy subpyriform enlargement which bears the seeds. This is composed of, first, a cellular cushion ; second, vascular cords supporting the seeds ; and third, a mass of irregular cellular tissue enveloping the whole.’ It is not plain from this account, or from the special description which follows it, whether the author considered the ‘ vascular cords ’ to be organs quite distinct from one another, or only differentiated tissue-strands traversing a homogeneous fundamental parenchyma. And this again makes it difficult to give a satisfactory account of the * mass of tissue’ which surrounds the whole. To settle this point requires in fact careful study of numerous sections in different definite directions, such as were not in existence when the above passage was written. Renewed examination of new, as well as old, preparations had somewhat advanced my knowledge, 1 Carruthers, loc. cit., p. 697. 2 Carruthers, loc. cit., p. 697. 435 of Bennettites gibsonianus, Carr . when I was studying the genus Bemvettites for my c Einleitung in die Palaeophytologie,’ and yet profounder study places me already under the necessity of modifying the account contained in that publication in some not unimportant points. To form the spadix the axis terminates in a slightly flat- tened hemisphere 1 on which a whole cluster of closely crowded organs takes its rise. Its succulent parenchyma, which consists of thin-walled cells with wide lumina, is generally destroyed, though it is better preserved in some of the slices in the British Museum. The vascular bundle-system of the shoot which bears the spadix comes to an end in the parenchyma ; beneath its convex apex may be seen numerous sections of small bundles which have different directions, and evidently supply the members of the cluster of organs which proceed from it. This is shown in a figure of Carruthers2, which is not however very perfect. On the convex upper surface of the apex, or ‘cushion’ as it is termed by Carruthers, the seed-bearing ‘ cords’ take their rise, a closely crowded cluster of erect stalk-like bodies united into a club-shaped mass. In studying it minutely we shall do well to begin with a transverse section immediately be- neath the upper convexity of the fleshy ‘ cushion.’ Examin- ing the section with a lens, we distinguish at once a main central mass and a thin zone which surrounds this and in its turn separates into two successive layers. The central portion presents the picture given in a figure by Carruthers 3, which shows the irregularly polygonal transverse sections of the ‘ cords ’ imbedded in a homogeneous fundamental tissue, the ‘ fleshy pericarp ’ of Carruthers’ description. However, exactly transverse sections teach us that this apparent fundamental tissue is by no means homogeneous, but is composed of the transverse sections of very many smaller organs pressed close to one another and filling up the intervals between the ‘ cords ’ 1 Carruthers, pi. 59, fig. 3, reproduced here in Plate XXV, fig. 9. * Carruthers, loc. cit., pi. 60, fig. 4. 3 See pi. 60, fig. 1. 436 Solms-Laubctch . — On the Fructification as has been described already in my Palaeophytologie 1. The transverse section of the ‘ cords ’ shows a stout peripheral layer of very thick-walled quite homogeneous and uniform cells, bounded on the outside by a simple epidermis without ramenta. In the longitudinal section these cells are seen to be elongated pointed fibres with thick walls which appear to be entirely destitute of pits. In ordinary states of preserva- tion this layer of fibres surrounds a cavity in the tissue filled with the structureless material of petrification, often also with pyrites, and containing only scattered remains of tracheal elements. Bounding the cavity there is regularly a simple layer of cells, firmly connected with one another laterally, but not essentially different in other respects from the fibre-cells ; this layer may not unreasonably be supposed to be an endodermis, though of this there is no proof. It is only in rare and exceptional cases that we find, instead of the central cavity, a more or less well-preserved delicate tissue of cells with rather wide lumina, in the middle of which is a weak and irregularly shaped tracheal strand consisting only of a few elements. The smaller transverse sections of the organs lying between these ‘ cords ’ are all pressed closely against one another, and owing to this pressure are very irregularly polygonal. They consist chiefly of thin-walled parenchyma, with isolated gum-passages, inclosed in a simple very strongly developed and distinct epidermis. In the centre of this homo- geneous parenchyma is the tracheal strand with essentially the same structure as that of the ‘ cords.’ On the longitudinal section I have not been able to demonstrate with certainty the portions of tissue which belong to these organs, on account of the close crowding and the winding course of all the con- stituents of the spadix (Plate XXV, Fig. 2, where a is the ‘cords/ and b the transverse sections of the organs lying between them). Going on to the peripheral zone of our section, we find that its inner layer is formed of the same elements as those 1 See the Palaeophytologie, p. 98 [Fossil Botany, Oxford, 1891, p. 96] ; and also Plate XXV, figs. 1 1 and 1 2 of the present paper. 437 of Bonnet tites gibsonianus , Carr . which are observed in the central portion of the spadix ; only the transverse sections of the ‘ cords 5 are here usually much smaller and fewer and farther removed from one another. On the other hand the small transverse sections of the in- terstitial organs are much more numerous and are at length almost exclusively present towards the outside (see Plate XXV, Fig. 2), as I have before endeavoured to show in the Palaeophytologie. Their well-preserved, dark-coloured, closely appressed epidermal layers contrast strangely with the often indistinct yellowish-brown inner tissue, and appear as irregular bands traversing the latter. Lastly, the outer layer of the peripheral zone cannot be resolved into transverse sections of different members, but consists of homogeneous dark-brown rather large-celled parenchymatous tissue, which surrounds a considerable num- ber of cells with strongly-thickened apparently lignified walls, and is covered towards the outside with an epidermis, which is present over its entire surface, and impinges immediately on the surrounding cataphyllary leaves. Not unfrequently sharp and tolerably deep indentations penetrate from without into this homogeneous external layer ; these indentations are covered with the epidermis, and probably answer to the cross-sections of a superficial areolation of the entire fructifica- tion ; they are particularly well and clearly seen near the base of the spadix in Fig. 12 of Plate XXV. Carruthers has endeavoured to illustrate the matter by a figure showing the details taken from the base of the spadix 1. If we now examine transverse sections of the spadix lower than the one just described, we find the structure essentially unaltered, except that we get in addition in the centre the transverse section of the upper convexity of the 4 cushion * surrounded by the constituents of the central portion already described. The lower the section, the narrower is the ring formed by this part of it, and the inner layer of the peripheral zone also gradually diminishes till at last, in the lowermost section, the slender compact tissue-mass of the outer layer is 1 Carruthers, loc. cit., pi. 60, fig. 3 ; also Plate XXV, fig. 8 of this paper. 438 Solms-L cutback. — On the Fructificatio?i the only one that remains, and this now enters into direct connection with the tissue which occupies the middle of the ‘ cushion ’ and becomes continuous with it. This continuity is particularly well seen in suitable longitudinal sections, especially in the median longitudinal section 1 or in one that is slightly inclined obliquely to the median2. Here I am obliged to give new drawings of the basal portions of both preparations, because the published figures give too little detail. My figures are perfectly accurate, and were drawn in my presence in the British Museum by Mr. Charles Berjeau. We see in the median section (Plate XXV, Fig. 10) how the homogeneous external layer takes its rise, far down in the periphery of the entire cluster of organs, directly from the axis of the spadix at the margin of the ‘ cushion ’ ; how it appears notched by penetrating fissures ; and lastly, how it extends round the entire spadix, becoming broader indeed, but less distinct, above. The other section (Plate XXV, Fig. 8) shows exactly the same thing ; but in consequence of its oblique direction it has touched only the upper part of the basal cushion on the lateral margin, so that its connection with the shoot which bears it is not seen. Below it, the section passes necessarily through the outermost marginal attachment of the homogeneous outer layer of the spadix in a partly oblique tangential direction ; hence the layer seems in this case also to be closed below. But the incisions are particularly distinct just at this part, and they unite here and there to form polygonal compartments or areolae (see Plate XXV, Fig. 8, a). But if the transverse sections are made through the upper portion of the spadix the picture is quite changed, for new constituents are introduced into it in the shape of the ripe seeds. These lie in a simple peripheral layer, surrounded by the closed tissue of the external layer, which is here rather strongly developed, and are everywhere nearly equidistant from its surface. They are generally cut through in an 1 Carruthers, loc. cit., pi. 59, f. 3. y Ibid. pi. 59, f. 1. of Bennettites gibsonianus , Carr. 439 oblique direction, so that the apex and the base are not touched, the testa therefore seems to be of uniform structure all round. It is only in preparations in which the section passes quite close beneath the apex of the spadix that we are able to see some of the seeds in exact transverse section. They are, in fact, so disposed that the longitudinal axis is everywhere perpendicular to the convex surface of the spadix 1. Exact longitudinal sections are not easy to obtain, but they show that each seed, which is about three milli- meters in length and two in breadth, is borne on a long stalk which is the structure hitherto termed the ‘ cord 5 by Carruthers ; and moreover that the seed is not, as a matter of fact, lodged, as it appears to be, in the tissue of the external layer, but fills a flask-shaped pit or depression, and has a slender process passing through the narrow open canal of the pit, and terminating at the surface of the spadix. This surface has a peculiar appearance from the number of seed-containing pits with their narrow orifices, and reminds us of Dorstenia , or, as Carruthers2 aptly suggests, of Tam - bourissa. Carruthers’ figure 3 is not readily intelligible with- out a knowledge of the object, and even then is not clear. The exactness with which the seed fills the pit which contains it is peculiar : there is nowhere the smallest interval between it and the wall of the pit, so that it is difficult to be quite sure whether or not there is continuity between the two, or how far it may extend ; I am obliged to suppose that at the base such continuity exists. In many seeds the contents are entirely destroyed, and then we find crystals and structureless remains of organic substance in their place. In other and not very few cases, they are very well preserved, and may be seen to be an embryo, in which radicle, hypocotyl, and the two fleshy cotyledons lying one on the other as in the bean, can be distinguished, if the 1 In Carruthers’ work they are represented in the transverse section in pi. 59, f. 5 ; in the tangential section in pi. 59, figs. 1, 2, 4 ; in the oblique radial section in pi. 59, fig. 3 ; and in Plate XXV, fig. 9 of the present paper. 2 Carruthers, loc. cit., p. 698. 3 Carruthers, loc. cit., pi. 59, fig. 6. 440 Solms-Laubach . — On the Fructification section is exactly longitudinal. The radicular end is slightly pointed ; the growing-point of the stem is visible in the best pre- parations as a short transverse line, above the middle of which the division between the two cotyledons comes to an end. In one seed, which I studied in the British Museum, and of which I possess a photograph through the kindness of Mr. A. Gepp (Plate XXVI, Fig. 6), the position of the growing-point is particularly prominent because local destruction of the tissue has produced a cavity directly above it filled with colourless stone. In all the embryos which I have seen the cotyledons occupied as a rule two-thirds, the stem-portion one-third, of the entire length. In some of them the tissue was in a good state of preservation (Plate XXVI, Fig. 5), especially in the cotyledons. This tissue is a parenchyma without intercellular spaces, consisting of brick-shaped cells arranged transversely to the surface of the cotyledons. In one case (see Plate XXV, Fig. 4, and Plate XXVI, Fig. 5) I could see that the tissue in the hypocotyl was formed of isodiametric poly- gonal cells, and was traversed by a central strand, the vascular bundle, from which a branch passed beneath the growing-point into each cotyledon ; but sections of such exact orientation are rare and accidental. If the longitudinal section, as sometimes happens, runs parallel to the bounding surface of the cotyledons, the embryo must necessarily appear as a homogeneous mass of tissue. In the much more common transverse or oblique sections 1 we see the circular, or in the latter case the more and more thoroughly ovoid, 1 See Carruthers as cited above, pi. 59, f. 4. This preparation has supplied the photographs of the transverse section of the seed (see Plate XXVI, figs. 1-4), for which I am also indebted to Mr. Gepp’s kindness. But the section looks differ- ently now from what it did when the figure was drawn, because the whole of the middle portion has crumbled away and the marginal portion only, which contains the seeds, is still preserved. It was the custom at that time in England, and is still to some extent, not to keep the slices under cover-glasses, their thickness making it rather inconvenient to do so. But this custom leads ultimately to decomposition of the upper surface, and, when pyrites is present, to the destruction of the entire preparation. It is simply the oxydation of the pyrites which has caused the disintegration and crumbling of the central portions of the slice in question, and this would certainly have been avoided by covering it with a cover- glass. of Bennettites gihsonianus , Carr . 44 1 section of the embryo, divided into two halves by a usually very distinct line which coincides with the long axis of the ellipse, and is continued through its whole length. This line is the division between the two cotyledons. Where the section is not too oblique and the preservation is also good, six points may be seen in each cotyledon which form a median transverse row, and are undoubtedly the transverse sections of as many vascular bundles (Plate XXVI, Figs. 1-4). Carruthers had not noticed this remarkable state of preserva- tion of the embryo ; he saw the parenchyma in the inner body of the seed, but he took it for the endosperm, for he says on p. 6 98 : ‘ Enclosed by these envelopes is the nucleus, with its membranous covering, and abundant albumen. The sub- rectangular cells of the albumen are obvious in several specimens, but I have not hitherto detected the embryo.’ Nevertheless there is an indication at least of the embryo to be seen in the corresponding figure1 ; a portion of the boundary line between the two cotyledons is given in the drawing, but it was probably taken for a merely accidental splitting. The embryo is surrounded by a thin membrane in the form of a brown line. In many cases the membrane lies immediately on the embryo, in others there is a fissure-like space between them filled with the material of petrifaction. We might be tempted to see in this interval (PI. XXVI, Figs. 2, 3) the trace of an endosperm which was present though in small quantity. But it is against this view, that the space in question is not found uniformly on all sides of the embryo, and further there is the important fact that a perfectly similar fissure is very often seen between the two cotyledons, where it can only be referred to shrinking. It must therefore be due probably to the same cause in the periphery, and we must suppose that the seed was without endosperm. As regards the brown in- vesting membrane, this appears usually as a simple line, its cellular structure has nowhere been demonstrated with any certainty ; but I have no doubt that it will be found to answer 1 Figure 9 in pi. 59. 442 Solms-Lauhach . — On the Friutification to the bounding-line of the nucellus, and therefore represents Williamson’s f nucular membrane.’ There is some appearance at its upper extremity of a conical process, which extends be- yond the radicular end of the embryo and enters the lower portion of the tubular prolongation of the testa ; this is best seen in the preparation on which Fig. 8 of PL XXVI is founded. Unfortunately after repeated examination I can still only speak thus conjecturally respecting the presence of the nucellar apex which contains the pollen-chamber. Turning now to the testa, we find three distinct regions in it which require separate consideration: (i) the middle portion inclosing the seed-cavity and the embryo in it ; (2) the basal region ; and (3) the apical portion which extends as a tubular canal beyond the seed proper, and pushes through the narrow orifice of the seed-pit till it reaches the surface of the fructification (PI. XXVI, Fig. 10). In the middle portion the testa is pretty closely applied to the ‘nucular membrane’ ; three distinct strata may be seen in it in all cases of good preservation ; the middle is a simple layer of short prismatic very thick-walled dark-brown cells, standing side by side as in palisade-tissue, while the inner and outer are formed of rather small-celled thin-walled tissue in several layers. In the inner stratum this tissue is often compressed and indistinct ; in the outer it forms a lighter area round the hard palisade-tissue, and seems to be continuous to a greater or less extent on the outer side with the surrounding wall of the seed-pit. At least I often found, when examining a single seed, that it was only in places here and there that I could perceive a sharp line of demarcation between the two parts (see PI. XXV, Fig. 5). Carruthers has figured this structure admirably1; the middle hard layer of the testa stands out sharply in all his drawings. The basal region is figured by Carruthers 2 in a slightly oblique longitudinal section which deviates from the median line towards the upper part. I have before me several similar preparations (see PI. XXV, Fig. 1). In these may be seen in 1 Carruthers, loc. cit., pi. 59, f. 8. 2 Carruthers, pi. 59, f. 7. of Bennettites gibsonianus , Carr. 443 the hard middle layer of the testa a small gap a , towards which the vascular bundle of the seed- stalk advances from below. Inside the hard layer is a small flat expansion of compact tissue, produced, as the surface-view shows, by the divergence from one another of the tracheal elements of the vascular bundle which terminates here (see PI. XXV, Fig. 3). On this point there can be no doubt ; we have here the behaviour which we so often find in the chalaza of gyrnnospermous ovules. If the testa is separated from the nucellus in breaking open the fructification, as sometimes happens, and the nucellus of the seed is exposed (PL XXV, Fig. 6 ), it shows, at the spot where the chalaza expands, a small impression from which a number of shallow furrows radiate towards the apex. The most difficult part to understand in the whole of the seed is the tubular prolongation of the testa beyond the apex of the nucellus. It is far from being so simple as it appears in Carruthers’ drawing \ and my own diagrammatic delineation is probably not quite correct, even if it comes on the whole near the actual condition. There are difficulties in the way of investigation which are quite insuperable with such scanty material. First of all the peculiar position of the seeds in the spadix makes it impossible to secure the necessary exactness in the direction of the sections. We can follow the general direction, but beyond this we are dependent on chance. Further, the upper extremity of the seed is so extremely slender that the slightest deviation from the median line at once produces oblique sections. Then the periphery of the spadix, which in this case is the important part, is usually particularly rich in pyrites, and this drops out when the slices are reduced to the needful thinness. Under these circum- stances, to obtain an exactly median longitudinal section in serviceable preservation is a piece of pure good luck, which has never fallen to my lot. The pyrites is also particularly embarrassing in the case of preparations which are tangential to the surface of the spadix, and in which we get a more or less exact transverse section of the apex of the seed ; more- 1 Carruthers, loc. cit, pi. 59, f. 6. 444 Solms-Laubcich. — On the Fructification over sections of this kind can hardly be made at all where the material is so scanty, for they involve a very considerable ex- penditure of the same. I have at my disposal only one such slice of very moderate character. The account which follows has therefore been obtained by combining together a multitude of very defective pictures with inexact orientation, and I regret that I cannot now reproduce the material on which it rests in the form of figures, or can do so only to a very limited extent ; but various attempts to draw or photograph these objects have had no satisfactory result. Still I believe that very thorough study of all the preparations, at least a dozen times during five or six years, has carried me as far as it is at present possible to go. Examination of the original preparations deposited in the British Museum and in the Museum at Kew will enable every one to judge for himself how far the following statements are to be trusted. The process, then, of which we have been speaking is in the lower half almost as broad as the seed itself, but narrows rather suddenly above that point, and assumes the form of a thin cylinder, which increases slightly in breadth and terminates in a valley-like depression in the surface of the spadix (PI. XXVI, Fig. io). Its form has been given in my earlier diagrammatic drawing, and is not open to any doubt. In the lower broader portion the testa is very thick, and seems to inclose the conical prolongation of the ‘ nucular membrane/ which has been already mentioned. But this is just the most obscure and doubtful point in the whole matter. The before-mentioned enlargement of the testa appears to be essentially due to the middle stratum, which consists in this part of several layers, and loses the palisade-arrangement of its cells. The outer and the inner strata are similarly preserved ; the latter, in a preparation in the Kew Museum, being evidently formed of several layers of thin-walled cells. At the spot where the neck of the seed begins to narrow into the slender cylinder, the hard middle stratum of the testa thins out and disappears, and the further continuation contains only delicate tissue and is solid on the transverse section, the of Bennettites gibsoniamis, Carr . 445 inner cavity having disappeared probably by the stopping up of the micropylar canal in the usual way. Whether this cylindrical process is formed entirely from the inner stratum of the testa, while the middle and outer strata come to an end at the place where it begins to narrow; or whether, while the middle hard stratum dies out, the inner and outer strata unite to form the process, I cannot positively say. In the former case the testa would probably have been developed from two integuments ; in the latter we may assume that it is only from one. After weighing all the circumstances I incline to the latter view. The question can only be settled by obtaining a slice which should be tangential to the surface of the spadix, and show the apex of the seed in exact transverse section. Unfortunately the only preparation of the kind before me is in too imperfect a state of preservation ; its appearance is reproduced, as far as it can be, in PI. XXVI, Fig. 7. The transverse sections of the apices of the seeds are seen as dark circles, sections of solid cylinders consisting of a small-celled tissue and surrounded by a single layer of larger cells. Lines radiating from one section to another may be distinguished at one part of the preparation. Their presence shows that the section has passed close beneath the surface of the spadix ; they answer to the bounding lines of the superficial areolae. As already explained, the ‘ cords,’ the seed-stalks of the spa- dix, each terminate in a seed. In each case the vascular strand enters the chalaza where it forms a small expansion ; its peri- pheral fibrous layer adheres all round to the basal portion of the testa (PI. XXV, Fig. 1), and gradually loses its dis- tinctive character. But whence comes the closed tissue forming the outer rind of the cone, in the depressions of which the seeds are imbedded ? My idea once was that this mass of tissue was produced by the upward growth of the peripheral portion of each seed-stalk forming a wall round the seed, and by the lateral fusion of all the seed-containing cavities thus produced. But this view can no longer be combined with the account of the facts here given. There remains only the possibility, that it is the structures with a smaller transverse section, lying 446 Solms-L cutback.— On the Fructification between the c cords/ which overtop the seeds, and, becoming clavately broader at the apex, unite there with one another to form the continuous external layer. The formation of the seed-bearing cavities is explicable in this way, and perhaps more naturally than by the earlier theory; and it finds a strong support in the circumstance that, as was shown above on p. 438, this continuous external layer may be followed to the very base of the fructification, and grows at the lowest margin directly out of the tissue of the ‘cushion,’ thus occurring in places where there are no longer any seed-stalks (see PL XXV, Figs. 8 and 10). From all these considerations we arrive at something like the following conception of the entire fossil. We have in the fructification (spadix) two kinds of organs of different character and closely crowded together; the seed-stalks (cords) di- verging above cluster-wise, and each terminating in a seed ; and the interstitial organs increasing constantly in length from the periphery of the cluster towards the inside, ap- pearing by themselves in the periphery but mixed with the seed- stalks further in, overtopping the seeds with their apices, and forming by the union of their apices the homogeneous tissue-layer of the surface of the fructification. In con- sequence of this arrangement every seed is sunk in a pit, the orifice of which then narrows over the seed owing to the lateral overgrowth of its walls 1. If we now try to realise the nature of the surface-view of a spadix having a longitudinal section answering to our scheme, we shall be inclined to think of it as marked with areolae or compartments corresponding to the upper extremities of the several interstitial organs, and between these there must be narrow openings leading to the seed-cavities below. After the account given above on page 438, of the inden- tations and areolations at the base of the surface of the spadix, I have no doubt that such a division into areolae is in fact present everywhere, and that each areola was raised, 1 See on this point the diagrammatic figure in my Einleitung in die Palaeophy- tologie [Fossil Botany, Fig. 5 A , p. 96]. of Bennettites gibsonianus , Carr . 447 probably as a pyramidal protuberance, above the surface. We see, in fact, quite plainly in many preparations that the surface of the spadix is uneven, and that the sections through the projecting parts appear as protuberances of varying height and steepness. According to our supposition this must be the case, since the areolae are cut through sometimes exactly in the middle, sometimes only on the margin, and therefore cannot possibly have the same height. Unfortu- nately we have never been able to get a surface-view of any portion of the spadix of Bennettites gibsonianus . But we get some help from a fossil which has been described by Saporta as Williamsonia Morihei 1. The figure which is given of it shows such absolute agreement with the fructifications of Bennettites , that I have no doubt whatever that it belongs to that genus. In this specimen the surface of the fructification was laid bare to some extent when the fossil was broken up, and it shows exactly the character which we have been endeavouring to show was probably that of Bennettites. As the specimen is changed into spathic iron, it will probably show structure ; it is very desirable that its anatomy should be examined, for it might possibly throw a welcome light on some still dark points. Saporta also associates Podocarya , Buckl. and Goniolina with his fossil. This is a bold step, and I can express no opinion on the matter, since Goniolina has never been found with the structure preserved, and the original specimen of Podocarya in the Museum at Oxford is at present not accessible, so that we have only the figure to depend upon, though that appears to be very good 2. There is one point which requires to be mentioned in conclusion. We have hitherto tacitly assumed that all the organs of the fructification, the seed-stalks and the inter- stitial organs, spring directly from the upper surface of the cushion of the axis of the spadix, and simply run through the whole of the cluster in the same number and position. But 1 Saporta, ‘ Paleontologie fran9aise, terrain jurassique,’ vol. iv. 2 Buckland, ‘ Geology and Mineralogy,’ 2nd Ed. : and Saporta, loc. cit., vol. iv, on Proangiosperms. I 1 2, 448 Solms-L cutback. — On the Fructification it might be otherwise, and a portion of the interstitial organs might possibly originate from the seed-stalks ; for the preparations which we possess do not show whether the organs of the central part, of which we have tranverse sections in slices from various parts of the spadix, are the same in all of them or not. Some might terminate inside the cluster, and others take their place. How then shall we interpret the facts as here presented in accordance with the principles of general morphology ? There can be no doubt about the axis which bears the spadix. But the seed-stalks may be axial members, or they may just as well be carpels, though in that case we should have the unusual phenomenon of terminal seeds. Then the inter- stitial organs may be aborted seed-stalks crushed between the others ; or they may, if the seed- stalks be axes, belong to a different category and be leaves. I leaned formerly to the former alternative ; but now that their peculiar connection with the formation of the homogeneous outer rind of the spadix has been ascertained, I incline rather to see in them the bracts and prophylls of the seed-stalks, to which must be added also such bracteoles, preceding the seed or flower, as may happen to spring from the seed-stalks. It appears therefore that there are the following possible modes of explaining the members which constitute the spadix : ( r ) All its organs are carpels, some being fertile with a single ovule at the summit of each carpel, some sterile, but projecting beyond the fertile carpels with their coherent apices, the whole forming a single flower. (2) All the organs are axial members, with no development of leaves, some being sterile, others end- ing in a flower, which, like that of Taxus , is reduced to a single naked ovule. (3) The seed-stalks are one-flowered axes, the interstitial organs are leaves, either exclusively bracts, in which case we should have a gymnospermous capitulum, sit venia verbo , like that of Compositae, or partly also prophylls and bracteoles of the lateral axes in more exact analogy with the head of Echinops or Dipsacaceae. Whatever the conclusion may be, the formation of the pits of Bennettites gibsonianus , Carr. 449 which contain the ovules is due to the cohesion of the apices of the interstitial organs, and in this, as in all similar cases, we see a contrivance for protection. Nor will it seem too fanciful to appeal, as to analogous conditions, to the closing of the carpels in forming the ovary, or to the position of the inferior ovary. If we suppose the enveloping coherent inter- stitial organs or leaves to spring from the seed-stalk itself, we should actually have an ovary, in rudimentary form indeed, but still of essentially similar character to the ovary in Angio- sperms ; we need only add a stigma to make it complete. But if the cohering members do not belong to the seed-stalk, but originate wholly from the axis of the spadix, this would certainly imply so primitive a stage in the formation of the flower that we could not point to any fitting analogue amongst existing plants. Still we might form an idea of it from the capitulum in Compositae, if we were to imagine the scales of the involucre and those on the receptacle all fully developed and coherent above, whilst the flowers were reduced to the simplest condition, to naked ovules. To realise this idea to some extent, we might call to mind the female capitula in the genus Xanthium. The effect, which is so often produced in our existing plants by intercalary growth of the tissue of the axes (Monimiaceae, Dorstenia ), would result in the present case from the cohesion of the last leaves of the main axis which bears the flowering shoot. The wall of the ovary thus formed would therefore belong to an older shoot-generation than the ovule ; and if we are prepared to adopt the standpoint of some morphologists and maintain that the ovule is formed from the leaf, the only change of importance required would be a change in the terminology, for the entire shoot would then become a flower with numerous leaves, some of which are sterile and serve to form the involucre, while the others bear the ovules. If in the course of the above account the Bennettiteae have constantly been compared with Cycadeae, it is because I am convinced that Cycadeae, notwithstanding all differences, are the nearest known allies of Bennettiteae, and on this point I shall be at one with nearly all palaeontologists and botanists. 450 Solms-Laubach'—On the Fructification Hitherto indeed stems of Bennettiteae have been placed with- out hesitation among Cycadeae, and it is possible that many of the mesozoic Cycad leaves grew on Bennettitean stems. But still it must not be forgotten that we have at present no proof of the correctness of this view. There are resemblances between the two groups which cannot be disputed ; but there are such important differences, especially in the structure of the flower, to be set against these, that we are driven to seek for other groups to fill up the chasm. If we suppose that, as a matter of fact, a real relationship exists between Bennettiteae and Cycadeae, it can still be shown most distinctly that the one group cannot be derived from the other, but that the two must be the terminations of different phyla springing from the same stock. For the Cycadeae, which we should naturally consider to be the younger group, are far behind the Bennettiteae in the complexity of the structure of the flower, while the Bennettiteae on the other hand show a much simpler and primitive structure in the vegetative organs. That the peculiar two-stranded girdle-forming leaf-tracesof Cycadeae are a comparatively new character which has made its appearance in their progress towards perfection, is proved in my opinion by the fact that in the flowering extremities of the shoots of the sympodium, where the vegetative development is less vigorous, we may observe in the course of the vascular bundles, which resembles that of Bennettiteae, a return to the primitive more simple arrangement \ This circumstance seems to me to be the most important argument for the approximation of the two groups. We do not know what was the appearance of the parent-group from which the two divergent phyla proceeded : but it must in all probability be sought in very remote epochs of the development of the earth, for we have some certain knowledge of the type of the flower in the genus Cycas from the base of the Lias ; and therefore I have no doubt that this parent-group may have given rise to various other derivative types besides those of Cycadeae and Bennettiteae. The idea which we frame for ourselves of the original parent-stock will 1 See my fuller account of this in Bot. Ztg., 1890, p. 177, of Bennettites gibsonianus , Carr. 451 of course be less satisfactory, the smaller the riumber of the derived forms from which we can abstract its characters. Saporta 1 unites Bennettites with Williams oniay but I cannot enquire at present whether or not there are any grounds for this proceeding ; he also places both genera in his ‘ stade proangiospermique.’ I have already endeavoured to show that there are in fact certain points of resemblance between the structure of the flowers in Bennettites and the formation of the ovary in Angiosperms, but that we know too little of the other characters to carry the comparison further. Though there is something very attractive in the idea of the ‘ stade proangio- spermique,’ yet we naturally hesitate when we find Saporta 2 conceiving of Progymnosperms and Proangiosperms simply as ancestral groups of our modern classes and saying : * In every way we see clearly that Gymnosperms and Angiosperms form two branches which have proceeded from one common stock of heterosporous Cryptogams, but have taken different direc- tions from the beginning.’ I cannot say that such filiation is impossible, but its probability seems to me to be diminished by the fact that I meet everywhere with accumulating evidence that descent works in more complex ways than by the method of simple alternatives. I suggested in a former paper3 that the formation of the superior and inferior ovary, of monosepalous calyces, of monopetalous corollas, of the in- florescences in the depressed urn-like receptacles of Ficusy of the ceramidia of Polysiphoniay of the conceptacles of Fticus , of the perithecia, pycnidia, and spermogonia of so many Fungi, is based on one and the same prin- ciple, which I have endeavoured to express by the term cuptdar formation . I look upon this as one of the means placed within reach of the plant in the course of its develop- ment for producing constantly increasing complexity of its organisation, while the repeated application, so to speak, of this means in a great variety of derived forms at very various 1 Saporta, G. de, ‘ Paleontologie Fran^aise, terrain jura ssique/ vol. iv. 2 Saporta, ‘devolution du regne vegetal/ vol. i (1885), p. 201. 3 Solms-Laubach, Bot. Ztg., 1889, p. 741. 45 2 Solms-L cutback- — On the Fructification times gives rise to an infinite number of different but always analogous results, because the substratum to be modified in each case has meanwhile been essentially changed. I have no doubt that we shall in time be able to refer other groups of phenomena also to common operative principles of adaptation. If this may be assumed, it is clear that Saporta’s Pro- angiosperms cannot represent a well-defined group in the genetic system, but must consist of the members of different analogous developmental series, which have under- gone evolution of a similar kind. The number of ancestral forms which pass through such a proangiospermous stage may then be very large ; their other characters may be very dif- ferent. How many of them, whether one or several, and which, have become the parents of our modern Angiosperms, may at present be beyond our conception. In the many phylogenetic speculations which have sought to explain the mutual relations of different classes in the vegetable kingdom, the botanical authors have as a rule disregarded or incorrectly applied the results of palaeophytology. It is much to be desired that these results should be more highly valued in the future. For this study, though now fragmentary and incom- plete, is much better suited than that of the classification of living plants to throw light upon the enormous difficulties which stand in the way of all attempts of the kind, and thus to warn us at every moment against precipitation, and to bid us be cautious. of Bennettites gibsonianus , Carr. 4S3 EXPLANATION OF THE FIGURES IN PLATES XXV AND XXVI. Illustrating Graf Solms’ paper on Bennettites. PLATE XXV. Fig. i. Median longitudinal section through the basal portion of the seed, showing the passage of the seed-stalk into the testa, and the small expansion within the testa, where the vascular bundle terminates. The entirely black places are deposits of opaque pyrites. Fig. 2. Transverse section of the periphery of the spadix taken from its lower portion where there are no seeds : showing at a a seed-stalk with its central bundle 4 (should be x) ; at b a number of interstitial organs in close contiguity ; at c the continuous external layer of the peripheral zone. At d is a small portion of the transverse section of one of the surrounding cataphyllary leaves (see Figs. 1 1 and 1 2 of this plate). Fig. 3. The small expansion of the vascular bundle at the chalazal end of the seed which, in the ripe seed, is situated in the hard testa. Fig. 4. Diagrammatic longitudinal section of the mature embryo. Designed chiefly from Plate XXVI, Fig. 5, with the help of many other preparations. (The number is misplaced. The figure referred to lies between Figs. 2, 3, and 5.) Fig. 5. Longitudinal section through the testa of two seeds close to one another, showing the hard layer and the inner layer on the two sides. The outer layer has evidently coalesced with the intermediate tissue. Fig. 6. Seed with the nucellus exposed by breaking away the testa, seen obliquely from behind, so that the basal depression and the lateral furrows radiating from it are brought into view. Fig. 7. Copy of a figure of Carruthers (pi. 59, fig. 1) ; oblique tangential section through the entire spadix, showing the seed-stalks (cords) obliquely cut through, and in the upper part the seeds. Fig. 8. Exact representation of the basal portion of the preparation in Fig. 7 : a new drawing by Mr. Berjeau of London, showing the interstitial organs between the seed-stalks and the continuous outer layer furnished with indentations ; at a indications of the areolae which answer to the indentations. The clear roundish patch above this spot represents an oblique section passing quite through the marginal portion of the cushion-like termination (‘ cushion ’) of the shoot, from which the seed- stalks spring (2/1). Fig. 9. Copy of fig. 3 on pi. 59 of Carruthers’ work, giving a not quite radial longitudinal section of the entire spadix. The cushion-like termination of the shoot from which the seed-stalks spring is particularly well shown. Fig. 10. New and perfectly accurate drawing, by Mr. Berjeau of London, of the basal portion of Fig. 9, showing the attachment of the seed-stalks, and especially that of the continuous external layer of the entire spadix to the cushion- like extremity of the shoot. The indentations of the outer layer answering to the superficial areolation are very plainly seen (2/1). 45+ Solms-Laubach. — On Bennettites. Fig. ii. Fragment from the periphery of an exactly transverse slice through the spadix, showing the sections of the seeds in the homogeneous external layer with its indentations. Internally to the seeds are the transverse sections of the seed-stalks, and of the small interstitial organs between them ; some of the cata- phyllary leaves round the spadix are also indicated. Drawn by Berjeau. Fig. 12. Similar fragment of a transverse section through the spadix with the surrounding cataphyllary leaves, but taken from a lower region of the spadix in which there are no seeds. The external layer with its notches answering to the areolation is very distinct. Drawn by Berjeau. PLATE XXVI. Figs, i, 2, 3, 4. Transverse sections of the seed, showing the two cotyledons of the embryo with their plane surfaces touching one another and their vascular bundle-traces ; from photographs by Gepp of Carruthers’ original preparations (see pi. 59, fig. 4, loc. cit.). In Figs. 2 and 3 the hard layer of the testa with its lighter cells is plainly marked. Figs. 2 and 4 show fissures beside the embryo and between its cotyledons, filled with structureless mineral substance. Figs. 5, 6. Longitudinal sections of embryos from one of Carruthers’ original preparations photographed by Gepp ; a in both figures the growing-point. The cleft between the cotyledons is very distinct in both figures ; and in Fig. 5 the tissue also of the cotyledons. It is more difficult to distinguish in Fig. 5 the central strand in the hypocotyl and the attachments of the bundles which pass into the two cotyledons. Compare the diagrammatic representation in PI. XXV, Fig. 4. Fig. 7. Attempted representation of a portion of a tangential section just beneath the surface of the spadix. The numerous irregularly- shaped lighter places are intended for parts filled with pyrites and disintegrated in slicing. The darker round figures are the transverse sections through the pointed extremity of the testa of the different seeds touched by the section. Some of them are united by straight lines, an indication perhaps of the areolation of the surface of the spadix. The figure is very imperfect, but it is the best I could get after many attempts to photograph the section had produced no serviceable picture. It was done with Winkel’s drawing-apparatus and is slightly magnified. Fig. 8. Sketch of the longitudinal section of a seed, showing, but not very distinctly, the conical prolongation of the nucellus (Williamson’s nucular membrane), which would probably inclose the pollen-chamber, if there is one. Fig. 9. Photograph of a radial longitudinal section through the seminiferous upper extremity of a spadix. The embryos with their two cotyledons are seen with perfect distinctness in the seeds. Fig. 10. Longitudinal section of the entire seed, showing the shape and structure of the tubular apical portion of the testa ; a the points of section of the circular zone where the middle stratum of the testa thins out, and the sudden narrowing of the entire process begins. Annals of Botany . SOLMS. — ON BENNETTITES. Vol V, PL XXV . Annals of Botany. c SOLMS. — ON BENNETTITES. Vol. V, PI. XXV. Annals of Botany . *;'x S/: " ° S O L M S, ON BENNETTITES. Vol. V, PI. XXVI. So Annals of Botany. Vol. V, PI. XXVI. SOLMS. — ON BE ETT IT ES. A Summary of the new Ferns which have been discovered or described since 1874. BY J. G. BAKER, F.R.S. Keeper of the Herbarium , Royal Gardens , Keiv. (Conclusion.) Genus 4 6. Oleandra, Cav. 3*. O. cuspidata, Baker, in Malesia, III, 44. New Guinea, Beccari. 3*. O. Whitmeei, Baker, in Journ. Bot. 1876, n. Samoa, Whitmee. Genus 47*. Luerssenia, Kuhn. 1. L. kehdingiana, Kuhn; Luerss. in Bot. Centralblatt, 1882, III, 77. Sumatra. Sori and indusium like those of Fadyenia. Fronds simple, lanceolate, rooting at the tip. Genus 48. POLYPODIUM, Linn. Subgenus Phegopteris. 1*. P. Krameri, Franch. et Savat. Enum. PI. Jap. II, 244 ; P. oya- mense , Baker, in Journ. Bot. 1877, 366. Japan. 1*. P. gymnogrammoides, Baker, in Journ. Bot. 1888, 229. China f Mount Omei, alt. 3000 feet, Faber. Very near P. Krameri. 8*. P. blandum, Baker; Phegopteris llanda , Fee, Mem. VIII, 91. Mexico ; Mirador, Schaffner , 222. 9*. P. Crossii, Baker, sp. n. Rootstock not seen. Stipe cas- taneous, 'naked, 6-9 in. long. Frond oblong-lanceolate, bi- pinnatifid, subcoriaceous, hairy only on the midribs of the pinnae beneath, 8-9 in. long, 2-2 J in. broad at the middle, narrowed to the base. Pinnae lanceolate, the largest an inch long, \ in. broad, cut down nearly to the rachis into oblong [Annals of Botany, Vol. V. No, XX. November, 1891.] 45 6 Baker —A Summary of the new Ferns segments in. broad, with incurved edges. Veins 5-6 -jugate, simple, erecto-patent. Sori round, medial. Andes of Loxa, Cross. Habit of IV. conterminum. 10*. P. Lechleri, Baker=P. laevigatum , Baker, in Syn. Fil. edit. 2, 505. Peru, Lechler , 2628. The name laevigatum used previously. 11*. P. sylvicoium, Baker, in Journ. Bot. 1881, 205. New Granada, province of Antioquia, Kalbreyer, 1807. 13*. P. omeiense, Baker, in Journ. Bot. 1888, 229. China ; Mount Omei, Faber , 1059. 15*. P. hydrophilum, Baker; Phegopteris hydrophila, F