PLATE LX. 



Naotildb bdcinum. 



Pago 412. 

 See PlateH 106, 107, 109. 

 Fig. 1. The dorsal side of a specimen which preserves the inner volutions, and shows the wide aperture. 

 Fig. 2. The same specimen, with the inner volution removed, showing the form of transverse section, posi- 

 tion of siphuncle, and surface-markings. 

 Fig. 3. A lateral view of the pi-ecediug specimen. Fi-om the Goniatite limestone, near Manlvus, N. T. 

 Fig. 4. A dorsal view of a larger individual, showing the form of apeiture and section of the inner volutions. 

 Several of the air-chambera are broken away, and the position of the siphuncle ia shown on the 

 convex and concave surfaces of the septa. Near Sulsville, Madison couiity, N. Y. 



Nautilus cornulum. 



Page 414. 

 Fig. 5. A ventral view of the specimen, showing the more cii cula'r form of section and of the aperture. 

 Fig. 6. A lateral view of the preceding specimen, showing the suture lines of the chambered portion of the 



shell, and the undulating strise of growth over the surface of the grand chamber. Near Caze- 



novia, N. T. 



GOMPHOCBRAS Sp. 



Fig. 7. A lateral view of a fragment, showing a moderate degree of curvalui-e and preserving eight air- 

 chambers, with the base of the chamber of habitation. iShore of Skaneatehg lake, N. Y. 



Nautilus liratus. 



Page 407. 

 See Plat* 57. 



Fig. 8. A figure of a gutla-percha impression, from the mould left in the matrix by the 8j)ecimen fig. 9, 

 showing the strong revolving plications and the obscure annulations near the a])ex. 



Fig. 9. A specimen preserving the greater part of the chambered portion of the shell in its natural propor- 

 tions. Several low, transverse undulations ai'e shown toward the apex, and the septal lines 

 are visible beneath the partially exfoliated shell. The revolving pliciitions, which are very 

 prominent near the apex, and are continuous on the concave dorsal side, liecome obsolete on 

 the ventral side as they approach the chamber of habitation. From the Goniatite limestone. 

 Schoharie, N. Y. 



