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ters of the inner cortex and stem revealed in the fragments sent by 
Doctor Derby to the late Professor B. Renault. 
The broad, round, or oval-round disc described by Renault as 
the leaf cushion or bolster is annulate at the border, and forms 
a flat zone about the leaf scar which, with its small thick- 
walled ring surrounding the minute nerve trace, is strikingly 
similar to the nerve trace and sheath in the Stigmarian svar. In 
one of the specimens described by Renault the leaf scars are nol 
so round as in that shown in Fig.11, Plate V, in our collections, while 
the leaf cushions are nearly contigous. In another example descri- 
hed by the same author the leaf scars are slightly hexagonal as the 
_result of pressure. 
The specimen in hand is from a smaller and younger branch than 
those figured in Renault’s paper. The stem is a little more than 
half-flattened, the cast being about 4 cm. in thickness. The scars 
are well shown at several points in the photograph. The wide angle, 
nearly 90 degrees, between the tio directions of the spirals of the 
phyllotaxy, is characteristic of the type. In this feature Lycopodi- 
opsis Derbyi agrees with certain Lepidophytic forms from the Middle 
Devinian of North America. 
The internal structure or the stem of Lycopodiopsis is described 
at some length by Renault, who interpreted the woody cylinder as 
discontinuous and but little different from that of Lycopodium; but 
Professor Zeiller, who has examined additional material sent by Doctor 
Derby from the same region, reports that the vascular cylinder is 
continuous and closely similar to that of Lepidodendron Harcourti. 
The examination of the superficial features of his specimens, in 
which the outer cortex does not seem to have been well preserved, 
convinced Professor Zeiller that the species belonged to Lepidoden- 
dron, the emergence of the nerve trace heing like that in Lepido- 
dendron selaginoides. The differences in the characters of the leaf 
cushions between Lycopodiopsis and Lepidodendron are explained 
by Zeiller as being due to partial decortication in the Brazilian 
type. 
In this opinion I can not agree. 
The characters of the so called leaf cushion are so clear, the 
surface so smoth, the contact with the surrounding surface of the 
stem so well marked by the annulate border; in fact, the whole 
combination of characters is so different from that of any par- 
