ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 199 



CRYPTOGAMS. 



Pteridophyta. 

 (By A. Gepp, M.A. F.L.S.) 



Phylogeny of the Pteridophyta.* — I. Browne continues her account 

 of the phylogeny and inter-relationships of the Pteridophyta, and treats 

 of the Filicales under the following headings : — Botryopterideae, Hy- 

 rnenophyllaceas, Schizaeaceae, Gleicheniaceae, Matoninea?, Cyatheaceae 

 and Polypodiacese, Loxomaceae, Osinundaceae, Salviniaceas, Marsiliaceae, 

 Psaroniea?, Marattiaceae, Ophioglossaceae. She appends a bibliography. 



Stipes of Clepsydropsis.f — P. Bertrand, during a study of the 

 Zygopterideae, has discovered the secondary rachis of Clepsydropsis, one 

 of "the most ancient of fossil ferns, and previously known only by the 

 primary rachis of their fronds : and further, by making use of the 

 peculiar structure of the leaf -traces of CUpsydropsis he has been able to 

 discover the stipes of the plant. This stipes is represented by the 

 fossils named by linger : — Syncardia pusilla, Hierogramma mysticum, 

 Arctopodium insigne, A. radiaium, Cladoxylon mirabile, C. dubvum, 

 C. centrah, Schizoxylon tseniatum. These seem to be referable to two 

 species. The author describes the character of the vascular bundles 

 and the secondary wood ; and concludes with an allusion to the facts 

 that these Cladoxyleae have been referred by turns to the Lycopodiaceae, 

 the Ferns, and the Medulloseas, as if all these types, traced to their 

 original forms, converge towards one common form, to which Clepsy- 

 dropsis, with its very primitive characters, would be infinitely nearer than 

 any other plant actually described. 



Foliar Gaps in the Lycopsida.} — E. C. Jeffrey has studied the 

 Lycopsida ( = Lycopodiales, Psilotales, Equisetales and Sphenophyllales) 

 in special reference to foliar gaps. The latter should occur immediately 

 above but not lateral to the corresponding leaf-traces, and the author 

 cannot therefore regard the perforations of the tubular central cylinder 

 which are found in Phylloglossum, Tmesipteris, the Lepidodendrese and 

 the Sigillarieee as true foliar gaps. Such gaps are also absent in the 

 cone axis and vegetative stem of Equisetum, and in the reproductive and 

 vegetative axes of Catamites. The Lycopsida are to be regarded as a 

 great natural phylum distinguished by " a pabngeneticaby rnicrophyllous 

 habit, the absence of foliar gaps in the tubular stele, and the possession 

 of sporophylls with adaxial sporangia." 



Young Stages of Dicksonia and Cyathea.§— G. B. Stephenson 

 publishes an account of his studies of the young stages of Dicksonia and 

 Cyathea. Cultures of the prothallia of Dicksonia squamosa, Cyathea 

 dealbata, C. medullaris and C. Cunmnghamiiwere grown ; and microtome 

 sections were made from them and the young sporophytes, permitting a 



* New Phytologist, vii. (1908) pp. 230-53 ; viii. (1909) pp. 13-31. 



t Comptes Rendus, cxlvii. (1908) pp. 945-7. 



t Bot. Gazette, xlvi. (1908) pp. 241-58 (2 pis.). 



§ Trans. Proc. New Zealand Inst., xl. (1908) pp. 1-16 (5 pis. and figs.). 



