PLATE 42. 
Fig. 1, 3. 252. 3. Cyrtoceras macrostomum. (Pag. 194.) 
1 a. A fragment, showing a partial section. 
1 b. A large fragment, showing the wide outer chamber. 
1 c. Section of the smaller extremity of the last. 
3 a. Dorsal view of a fragment probably identical : the strise in the figure do not bend so abruptly as in the 
original. 3 b. Lateral view of the same. 
Fig. 2, 3. 253. 4. Cyrtoceras constrictostriatum. 
2 a. A fragment, showing several of the septa and a part of the outer chamber. 
2 b. Transverse section, somewhat compressed, showing the position of the siphuncle. 
3 c. A fragment, showing the surface markings. 
3 d. Section of the same, which does not show the siphuncle. 
(Pag. 195.) 
Fig. 4. 
254. 
5. 
Cyrtoceras multicameratum. 
(Pag. 195.) 
Fig. 5. 
255. 
6. 
Cyrtoceras arcuatum. 
(Pag. 196.) 
5 a. Lateral view of the specimen, which is crushed towards the lovrer extremity. 
5 b. Section of the same. 
5 c. The base of a parasitic coral, or of a crinoid, attached to the fossil. 
Fig. 6. 256. 7. Cyrtoceras camurum. (Pag* 196.) 
Fig. 7. 258. 11. Orthoceras arcuoliratum. (Pag. 198.) 
7 a. A fragment near the apex of the shell. 
7 b. A fragment of larger diameter, showing the convexity of a septum. 
7 c. Transverse section, showing the central position of the siphuncle. 
Fig. 8. 259. 12. Orthoceras teretiforme. (Pag. 198.) 
3 a. Fragments of two specimens connected by the dotted lines. The annulations are represented too broad. 
S b. Section showing the position of the siphuncle. 
