PLATE 41. 



Fig. 1. 247. 2. Cyktolites thentoneksis. (Pag- 189.) 



1 a. Lower sorface of an imperfect specimen. I b. A portion of the surface stris enlarged. 



1 e. Section of the shell below the apertare ; the upper surface of the figure being the dorsal margin. 



Fig. 2. 250. 1. Cybtocebas lauellosum. (Pag- 1^3.) 



2 o. Lateral view of the fragment. 2 b. Dorsal view of the same. 2 c. Magnified portion of the surface. 



Fig. 3. 248. 3. Cybtolites filosum. (Pag. 190.) 



:i a. Lateral view of the specimen imbedded in stone, the apex being concealed. 



.3 b. View of the dorsal side of a small portion of the shell, showing the arched strie. 



Fig. 4, 6. 251. 2. Cybtocebas annulatum. (Pag. 194.) 



4 a. A large fragment (a cast), retaining the annulations. 



4 6. A smaller fragment, retaining the shell and transverse striie. '""*' 



4 c. Section of the last, showing the siphuncle. 



i d. A portion of the surface magnified. « 



5. A fragment of the same species, nearer the aperture. 



Fig. 6, 7. 267. 1. Ohcoceeas constbictum. (Pag. 197.) 



6 a. View of the ventral side of an imperfect specimen. 



6 b. Lateral view of the same, showing the sudden contraction below the outer chamber : aperture imperfect. 



6 e. Section of the lower extremity, showing the small dorsal siphuncle. 



6 d. A smaller specimen, of the same form as the last. 



6 r. A shorter and more ventricosc specimen. (The transverse lines on the upper half of the figure, indicating 



septa, are incorrect.) 

 t>/. The apicial extremity of the fossil. 



7 a, e. Dorsal and lateral views of a fragment, showing the direction of the septa. 



7 b, d. Sections of different specimens, showing the position of the siphuncle, and the narrowing of the dorsal 

 side of the sheU. 



