426 



STUDIES IN FOSSIL BOTANY 



are the most extensive and, at present, the best in- 

 vestigated. 



The leaves of Neuropteris are of a very large size, 

 bipinnate, tripinnate, or even quadripinnate in com- 

 position, with ovate or oblong leaflets somewhat 



Fig. 161. — Ne7iroj>tcris keterophylla. Part of vegetative frond, slightly enlarged. 

 From a photograph by Mr. R. Kidston, F.R.S. 



cordate at the base, and usually attached to the rachis 

 by a short stalk. The median nerve of the pinnule is 

 distinct till near the end, where it breaks up into 

 smaller dichotomous nervules ; similar nervules are 

 given off from the sides of the median nerve throughout 

 its length ; they leave the latter at an acute angle, and 

 bend outwards to the margin (Fig. 161). The fronds 

 recall those of some recent Osmundas. 



