400 DR. E. A. NEWELL ARBER ON PSYGMOPHYLLUM FROM 
to be confidently assigned to this genus. Nathorst himself compares it with the 
American plant here described as P. Brown? (Dawson). 
Distribution.—Upper Devonian of Mimersthal, Spitzbergen. 
6. PsYGMOPHYLLUM KIDSTONI, Seward. 
1903. Psygmophyllum Kidstoni, Seward, Ann, S. African Mus. vol. iv. p. 93, pl. 12. fig. 1. 
1908, Psygmophyllum Kidstoni, Seward, Quart. Journ. Geol. Soc. vol. lxiv. p. 123. 
Type.—In the South African Museum, Cape Town. 
Diagnosis.—** Vegetative shoots woody, bearing spirally disposed leaves. Leaves wedge- 
shaped, reaching a length of 13 cm., usually divided by a deep median sinus into two | 
narrow wedge-shaped lobes, truncate distally, and tapering gradually to the proximal 
end of the lamina. Leaves sessile, attached to the axis by a narrow base. The lamina is 
traversed by numerous spreading and occasionally forked veins following a course parallel 
to the edge of the leaf. Organs of reproduction unknown.” (Seward, 1908, p. 93.) 
Remarks.—As Professor Seward remarks, his species closely resembles P. flabellatum 
(Lindl. & Hutt.) Only a few of the leaves of this specimen are, however, attached to 
the fairly stout axis, and these show no sign of the long, sheathing bases found in the 
English species. The preservation of the lower parts of many of the leaves is no 
doubt imperfect in the South African specimen, and therefore too great weight must 
not be placed on the apparent absence of this character. At any rate the leaves here 
appear to possess a much narrower base than in P. flabellatum. The bilobed nature of 
the leaf, in some cases split almost to the base, is another point of difference, for while 
the leaves of P. flabellatum are often apparently deeply split, it is not possible at present 
to decide how far this feature was natural and constant. Certainly many of the leaves 
(cf. text-fig. 1, p. 395) were not deeply divided. 
Distribution—The Permo-Carboniferous (Ecca beds) of Vereeniging, Transvaal, 
S. Africa, associated with the Glossopteris flora. 
Species exclusa. 
It will be remembered that Schimper when instituting the genus Psygmophyllum, in 
which P. flabellatum (Lindl. & Hutt.) was placed first, perhaps because it was the 
earliest-described species, also referred to his new genus two plants from the Permian of 
Russia, which have since been known as P. expansum (Brongn.) and P. cuneifolium 
(Kutorga). There are specimens of both these plants in the British Museum, where I 
have had an opportunity of examining them. The question whether these plants should 
still be retained in the genus Psygmophyllum is a very difficult one. After a comparison 
of the actual specimens in London, and of all the figures of these plants which have been 
published, I am inclined to exclude them (at least provisionally) on the grounds that 
they are best referred to a separate genus. They are no doubt related to Psygmophyllum, 
just as they are to Rhipidopsis, Schmalhausen, and very probably the three genera all 
belong to one family. 
