PLATE XX. 

 Oligocarpia missouriensis D. W. 



(Page 66.) 



Fig. 1. Portion of primary pinua shon'iug slender flexuoae rachis and graceful lateral piun.T. The 

 piuna3 in the upper portion are fertile, the sori being expressed as small rounded eleva- 

 tions on the ventral surface of the pinnules. U. S. Nat. Mus., 5694. 

 la. Enlarged detail showing sterile pinnules on same slab. X2. 

 2. Small sterile pinna-. U. S. Nat. Mus., 5619. 



Sphenopteris (Grossotheca) ophioglossoides Lx. sp. 



(Page 60.) 



I'lG. 3. Portions of secondarj- sterile pinua'. U. S. Nat. Mus., 5698. 



3n. Enlarged detail to show outline and nervation of pinnules. x2. 



36. Pinnule of No. 5698 still further enlarged to show the nervation. The convex margin and 

 slightly depressed nervation are imperfectly indicated in Fig. 3. X 6. 

 4. Portion of the same frond as that seen in the left of Fig. 3. U. S. Nat. Mus., 5698. 



Sphenopteris sitbcrentjlata Lx. sp. 



(Page 64.) 

 Fig. 5. Piun:e showing pinnules of ordinary type. Collection of Dr. J. H. Britts, Clinton, Missouri. 

 350 



