PLATE 47. 



Fig. 1, 2. 274. 6. Endoceras proteiforme, car. tenuistsiatum. (Pag. 209.) 



1 a. A small and slender specimen of this species. 



1 b. A portion of the surface enlarged, showing the cancellated lines. 



■2 a. This specimen presents very similar surface markings, and cannot be distinguished from the last, though 

 the transverse stria are less prominent. The specimen consists of a double or triple tube ; the outer one 

 2 ft showing externall} marks of septa, which are distant about one-fourth the diameter. The shell is 

 exfoliated, and the surface markings are unknown. 



2 e. An enlarged portion of the surface : the longitudinal stris are too strong in the figure. 



2 d. A small portion still farther magnified, showing the proportionate size of the transverse and longitudinal 

 striae. 



2 e. Transverse section of the specimen 2 a, showing the proportional diameters of the two, and the section 



of a still smaller tube within 2 a. 



Fig. 3. 269. 22. Orthoceeas juncettm. (Pag. 204.) 



3 a. A fragment denuded of the shell, showing a part of the outer chamber, and septate ]>ortion of the tube. 

 3 ft. A smaller specimen, showing the marks of septa which appear to be slightly oblique, 



3 £. A small fragment, showing the convexity of a single septum. 



3 d. A section of the last, showing the central position of the siphuncle. 



3 e. A small fragment, showing the closer approximation of the septa near the outer chamber. 

 3/. A small fragment, preserving the shell and the striated surface. . • 



Fig. 4. 276. 8. Endoceras proteiforme, car. lineolatum. (P^g- 211.) 



4 a. A fragment from the apex of one of these tubes, which is septate as in the larger specimens. 

 4 6. A transverse section. 



4 e. A fragment which is annulated near the apex, and septate to the extreme point. 

 4 d. Section near the apex. 



4 c. A fragment of a similar young shell, where the lamelloae stris have become vesicular, giving a rough 

 scaly appearance to the surface. 



