CUTICULAR STRUCTURE OF PSILOPHYTON. 377 
On the Cuticular Structure of the Devonian Plant Psilophyton. By W. N. 
Epwarps. (Published by permission of the Trustees of the British 
Museum ; communicated by J. Ramssottom, O.B.E., M.A., Sec. L.S.) 
(PLATE 37 & 5 Text-figures.) 
[Read Ist November, 1923.] 
INTRODUCTION, 
THE Geological Department of the British Museum (Natural History) 
possesses several specimens of the Devonian genus Psilophyton from 
Gaspé and other localities in Canada which were collected and presented by 
Sir J. W. Dawson, and some of which were actually figured by him. This 
Canadian materia] presents several points of interest, of which the most 
important is the presence in some specimens of a cuticle which could be 
detached from the rock and macerated with Schultze’s mixture in the usual 
manner. The present communication deals with the epidermal structure as 
seen in cuticular preparations of Psilophyton princeps Dawson, one of the 
earliest land-plants with which we are acquainted. 
Fro. 1. 
Psilophyton princeps Daws. 
Fragment of stem from specimen V.14918. x 2. 
Most of the specimens dealt with are labelled P. princeps var. ornatum 
Daws., but as White (1905, p. 61) and Halle (1916, p. 14) have shown, 
the so-called variety ornatum is really the type of the species, and should 
henceforth be referred to Psilophyton princeps. The best preparations were 
obtained from specimen V. 14918, a fairly accurate drawing of which was 
given by Dawson (1871, pl. ix. fig. 100; the figure is natural size). This 
specimen is a small piece of dark sandstone on which are scattered fragments 
of the stems of P. princeps showing the typical spines or emergences of the 
species. One of these fragments, about 3mm. in diameter, is refigured here 
