PLATE 45. 



Fig. 1, 274. 6. EnDOCEEAS PROTEIFORME, ««?•. TENUISTKIATUM. (Pag. 209.) 



1 a. Fragment of the young shell, natural size, showing only the transverse striaa. 

 1 b. Enlarged portion, showing the longitudinal striee. 



Fig. 2, 3, 5. 275. 7. Endoceras pkoteiforme, var. tenuitextum. (Pag. 210.) 



2 a. A fragment of a tube destitute of septa, presenting strong transverse and longitudinal striae. 



2 J. A portion of the surface enlarged. 



3 a. A specimen with finer striae, showing the marks of septa. '3 b. Portion of the surface enlarged. 



5 a. This specimen presents a double tube or sheath, the outer one (or embryo tube) being entirely smooth ; 



while the inner one, which is but little smaller, is marked by longitudinal and transverse striae as in the 



preceding figures. 

 5 i. A portion of the same enlarged to show the stria;. 

 5 c. A section of the same, showing no septa or siphuncle. 



Fig. 4. 276. 8. Endoceras proteiforme, var, uneolattjm. (Pag. 211.) 



4 a. A young shell, with the outer chamber and apex broken off. 



4 6. Transverse section of the larger extremity, showing the position of the siphuncle. 



4 c. A fragment of the smaller extremity of the shell, which is annulated by fine sharp ridges. 



4 d. The same enlarged. 



4 «. A fragment of another tube, marked like 4 a, showing at the lower extremity a septum and siphuncle. 



