510 PTERIDOSPERMS, ETC. [CH. 



Glossopteris. Comparison may be made also with the Palaeozoic 

 leaves described in the first instance by Lesquereux and more 

 recently by Renault and Zeiller as species of Lesleya^ (fig. 347). 



Bledmoxylon talbragarense, Etheridge. Fig. 343. 



Under this name Etheridge^ described some specimens 

 from the Permo-Carboniferous Coal-Measures of New South 

 Wales, which he regards as a fern, comparable, in the possession 

 of a cylinder of secondary xylem, with the recent genus 

 Botrychium and with Lyginodendron and other members of 

 the Cycadofilices. The slender axis (1 — 3 mm. in diameter) 

 appears to consist of a zone of radially disposed tissue 

 (fig. 343, C, x), which is probably of the nature of secondary 

 xylem, enclosing a pith and surrounded externally by imperfectly 

 preserved remnants of cortex. Unfortunately no anatomical 

 details could be made out, but the general appearance, if 

 not due to inorganic structure, certainly supports Etheridge's 

 determination. The stem bore at intervals clusters of linear- 

 lanceolate leaves (reaching 12 mm. in length) in close spirals 

 (fig. 343, A and B); the leaves are characterised by a strong 

 midrib and forked secondary veins. Small "pyriform" bodies of 

 the nature of scale-leaves occur in association with the fronds 

 (fig. 343, B, s). 



In his description of this interesting plant, Etheridge quotes 

 an opinion which I expressed in regard to the comparison of the 

 stem with those of Botrychium, Lyginodendron, and other 

 genera. No satisfactory evidence has been found as to the 

 nature of the fructification. Although the leaves oi Blechnoxylon 

 are much smaller than those of Olossopteris, I am now disposed 

 to regard the genus as closely allied or even generically referable 

 to Glossopteris. The crowded disposition of the leaves is like 

 that in Glossopteris, shown in fig. 339 and in the figures published 

 by Etheridge and by Oldham ; the association of scale-leaves 

 and foliage-leaves is another feature in common. The absence 



1 Lesquereux (79) A. PI. xxv. ; Renault and Zeiller (88) A. PI. xxiii. See 

 p. 517. 



•■i Etheridge (99). 



