PLATE XLI. 



Callipteridium SuLLiVANTii (Lx.) Weiss. 

 (Page 123.) 



KiG. 1. Young pinna- developing in Odontopteroid form, constricted at base. U. S. Nat. Mus., 5479. 



2. Apex of compound pinna, showing Neuropteroid constriction of large pinnules, before passing 



into the pinnatifid stage. U. S. Nat. Mus., 5481. 



3. Incomplete fragment, becoming subloliate. U. S. Nat. Mus., 5482. 



Netiropteris MISSOURIENSIS Lx. 

 (Page 130.) 



Fig. 4. PinniE showing characteristic forms of lateral and terminal pinnules. U. S. Nat. JIiis., 5631. 

 5. Example with smaller pinnules of the same species. U. S. Nat. Mus., 5472. 



Neuropteris dilatata (L. and H.) Lx. 



(Page 137.) 



Fig. 6. Portion of No. 5672 (shown in PL XLII, Fig. 1), showing the nervation; natural size. 

 Enlarged detail of small area to show vascular strands in the lamina between the larger 

 nerve bundles. The number and distribution of the strands is greater than is represented. 

 They are somewhat irregular. x2. 



6a. 



LiNOPTERIS GILKERSONENSIS D. W. 

 (Page 139.) 



Fig. 7. Slightly undersized pinnule, showing nervation. U. S. Nat. Mus., 5485. 



8. Large pinnule showing linear form and peculiar meshing of the nerves. U. S. Nat. Mus., 5485. 



Alethoptesis ambigua Lx. 



(Page 113.) 



Fig. 9. Fragment showing young pinna, with irregular pinnules. The specimen was identified by 

 Professor Lesquereux. Lacoe collection. U. S. Nat. Mus., 3590. 



DiCRANOPHYLLTJM? Sp. 



(Page 272.) 



Fig. 10. Fragment from the macerated specimen photographed in PI. LXXIII, Fig. 1. It should per- 

 haps be regarded as an Alga. U. S. Nat. Mus., 6076. 



