PLATE XI Y. 

 Sphenopteris missouriensis D. W. 



(Page 43.) 



. 1. Segment allowing lateral pinnne in lower part of a primary (?) pinna. The broad rachis 

 indicates a large pinna of considerable length. U. S. Nat. JIus., 5663. 

 la. Enlarged detail of ultimate pinna of the same, to illustrate obtuse aud imperfect lobation. 



X2. 

 2. Apical portions of lateral pinnfe of the same species. U. S. Nat. Mus., 5664. 

 2a. Enlarged detail of pinnules from the same. X2. 



338 



