PLATE XCVI. 



CtRTOCBRAS EaaBNIUM. 



Page 369. 



Bee Plates 36, 47, 97. 



Tig. 1. Ventral view of the internal mould of a fi-agment, showing the extension of the transvei-se ridges of 

 the test into the suiTOunding mati-ix, and th« sinus of the annulations on the ventral side. 



Fig. 2. A small fragment of a large example, showing the sinus of the ornaments on the ventral side. 



Fig. 3. A gutta-pei-cha mould of a laterally compressed fragment, showing the distance between the costffi 

 and the effects of the compi-ession on the sinus, which is made much deeper and abrupt. 



Fig. 4. Lateral view of a large, imperfect individual, showing the prominence and frequency of the expan- 

 sions of the test. The figui-e is from a gutta-percha mould of the impression of the shell in the 

 rock after it has been removed in the process of weathering. 



Fig. 5. A fragment preserving the internal mould of a portion of the tube, and the mati-ix of the lower 

 portion, showing the concavity of the septa and the extension of the lamellie. 



Fig. 6. A portion of the chamber of habitation with two attached air-chambers, showing the sinus of the 

 ornaments and the greater frequency of the ridgen toward the aperture. The walls of the air- 

 chambers show a furrow left by the removal of the siphuncle in the process of weathering. 



Fig. 7. A septum of the preceding, showing the position of the siphuncle and the amount of compression, in 

 a ventro-doi-sal direction, to which the tube has been subjected. 



Fig. 8. Venti-al view of the chamber of habitation of an individual which has been laterally compressed. 



Fig. 9. The septum of the preceding, showing the position of the siphuncle and the amount of the com- 

 pi'ession. 



Fig. 10. An enlargement of the surface, showing the fine lamellose lines of gprowth and the traces of longi- 

 tudinal stnae. 



Fig. 11. An enlargement of the surface and ornaments, taken from a gutta-percha mould of the impres«ion 

 made by the solution of the test in process of weathering. 



The specimens of this species here illustrated are from the Schoharie grit, in the counties of 

 Albany and Schoharie, N. Y. 



