PLATE l^yLXXY.— Continued. 

 Okthoceeas emaoeeatum. 



Page iM. 

 See Plate 39. 

 Fi^. 10. A septate fra^^ent, showing the depth of the chambers. The specimen is broken and flattened 

 from compression. Hamilton group. Jaycox Run, Genesee county, iV. T. 



CTBTOCBRAS DEN8UM. 

 Page 363. 

 Fi(f. 17. A chambered fragment, showing the apical angle of the tube and the regular depth of the air- 

 chambers, with the straig-ht and horizontal septal sutures. Hamilton group. Cuinberland, Md, 

 Fig. 18. Septum of the preceding, showing the size and position of the siphuncle, the areola ai-ound its inser- 

 tion in the septa, and the transverse section of the tube. 

 Fig. 19. A longitudinal section of a fragment, showing the elements of the siphuncle, the concavity of the 

 septa, and a slight exogasti-ic curvature of the tube. Hamilton group. Cumberland, Md. 



