PLATE 77 a. 



h'ig. 1. 701. 1. Thochoceras gebhardii. ( Pag. "o5.) 



1 «. A'icw of the tiaso of t!ic3 inecediiig speoiiiien, after tlie i-ciiioval of (lie lust volutinii, showing the (lireo- 



tion of the septa. 

 1 b. Tlie base of another spceimen, which has the upper [xa'tion eiieUiseJ in wilid lim<'stonc. 

 1 c. A transverse section just above the first vohitlon. 



1 d. \ transverse section, abotit one half or two-thirds of a volntion above the npcrtnrc. 



Fig. 2. 703. 4. Oncoceras expansum. ( Pag. .3:17.) 



2 a. Lateral view of tlie specimen. 



•J 6. Transverse section, showing the position of siphuncle. 



