100 MOLLUSCA. 



No. 202. [492. Cast]. Ammonites gigas, Zieteu. 



This species belongs to the group "Coro- 

 nati." From the Upper Oolite, Yonue, 

 France. 



Diameter, 9. 



No. 203. [494, Cast]. Ammonites giganteus, Sow. 



This is assigned to the group " Planulati" of Von Buch. From the Upper 

 Oolite, Isle of Portland, England. Diameter, 26. 



No. 204. [495, Cast]. Ammonites Goliathus, d'Orb. 



On pedestal. This specimen, an inner cast of a species allied to the A. 

 modiolaris, shows well the outer markings of the lobes, and the floor of one 

 of the septa. The original is from the Middle Oolite of Dives, France. 



No. 205. Ammonites Henleyi, Sow. 



Pictet refers this to the group "Macro- 

 cepliali." This is one of the most sj^m- 

 metrically ornate of Ammonites. From 

 the jMiddle Lias, Charmouth, England, 

 and now in the Ward Collection, Univer- 

 sity of Rochester. 



Diameter, 6. 



