mosa.saurhxe. 273 



Genekically Undetermined Specimens. 

 A. From the Cretaceous of Maastricht. 



R. 291 a. The crown of a large tooth. This specimen is nearly 

 symmetrical, and has very prominent carinae, which form 

 distinct ridges on the fore-and-aft borders. 



Egerton Collection. Purchased, 1882. 



R. 291 b. A tooth of smaller size, with the crown somewhat 

 compressed, curved, and carinated. This tooth might 

 apparently belong either to Liodon or to the hinder part 

 of the mandible of Mosasaurus. Same history. 



R. 1231. A smaller tooth of similar type. No history. 



R. 1232. The crown of a small tooth, with one surface faceted. 



No history. 



44822. A small imperfect cervical vertebra. In its depressed cen- 

 trum this specimen agrees with the trunk vertebra of 

 Liodon perlatus. Presented by B. Bright, Esq., 1873. 



B. From the Upper Chalk of England \ 



43193. The crown of a tooth of medium size ; from Gravesend, 

 (Fig.) Kent. Figured by Mantel! in his ' Medals of Creation,' 

 vol. ii. fig. 229, as Mosasaurus hofmanni. This tooth 

 resembles the Maastricht specimen No. E. 291 b. 



Wetherell Collection. Purchased, 1871. 



48940 d. The crown of a very large tooth ; from Norwich. This 

 specimen approximates to the Maastricht specimen 

 No. E. 291 a. Purchased, 1878. 



39423. The crown of a small tooth, with one surface flattened as in 

 Mosasaurus ; from Sussex. 



BoiverbanJc Collection. Purchased, 1865. 



39425. The crown of a tooth resembling No. 39423. Same history. 



41383. The crown of a very similar tooth; locality unknown. 



Purchased, 1869. 



47954. The crown of a tooth of the same type ; from Maidstone, 

 Kent. Presented by the Hon. E. Marsham, 1^77. 



1 It should be observed that Mosasaurus gracilis, Owen, ' Cretaceous Reptilia' 

 (Mon. Pal. Soc.), pt. i. p. 31, is founded on the jaw of a fish. 



T 



