TAB. VIII. 

 Mosasaurus gracilis ',jnat. size. 



Fig. 



1. Side view of a hinder dorsal vertebra. 



2. Back view of ditto. 



3. Two caudal vertebrae. 



From the Upper Chalk, near Lewes. In the Mantellian Collection. British 

 Museum. 



Mosasaurus Hoffmanm. 



4 . Side view of a hinder dorsal vertebra, nat. size. 



5. Back view of ditto. 



From the Cretaceous Beds, at Maestricht. In the British Museum. 



6. The half of a vertically and longitudinally bisected vertebral centrum of a 



Mosasaurus gracilis, which was partially enclosed in a nodule of flint, from 

 the Upper Chalk, at Kemptown, Brighton. The siliceous matter has 

 infiltrated itself into much of the cellular structure of the middle part of the 

 centrum. The densest part of the cellular structure is near the concave 

 surface of the vertebra. 



In the Collection of Dr. Man tell, F.R.S., by wiiose obliging permission it is 

 figured for the present Monograph. 



