20 TJNGULATA. 



13 (0. C). The second right upper true molar, in a much-worn con- 

 dition ; from " Big-Bone-Lick." Purchased. 



17373. The germ of the second left upper true molar ; from Mis- 

 souri. Purchased. About 1844. 



M. 451. The second left upper true molar; from " Big-bone-Lick." 



EnnisJcillen Collection. Purchased, 1882. 



17312. The second left upper true molar ; from Missouri. 



Purchased. About 1844. 



17334. The germ of the third right upper true molar ; from Mis- 

 souri. Purchased. About 1844. 



17367. The third right upper true molar, unworn ; from Missouri. 



Purchased. About 1844. 



17393. The germ of the third right upper true molar ; from Mis- 

 souri. Purchased. About 1844. 



17326. 'The third right upper true molar, with the first ridge slightly- 

 worn ; from Missouri. The fourth ridge and the hind 

 talon are very small. Purchased. About 1844. 



17324. The third right upper true molar, in an early stage of wear; 

 from Missouri. The fourth ridge is very large, and the 

 hind talon double, so that the specimen might be described 

 as having five ridges and a talon. 



Purchased. About 1844. 



M. 451 a. The third right upper true molar (imperfect) ; from " Big- 

 Bone-Lick." This tooth agrees in character with No. 

 17326. EnnisJcillen Collection. Purchased, 1882. 



17366. The germ of the third left upper true molar; from Missouri. 



Purchased. About 1844. 



17403. The germ of the third left upper true molar ; from Missouri. 

 This specimen is much smaller than the preceding, and 

 the ridges are placed closer together. 



Purchased. About 1844. 



7437. The much-worn third left upper true molar ; from Ohio. 



Mantell Collection. Purchased, 1836. 



12 (0. C). A third upper true molar; from North America. This 

 tooth belonged to a very old animal, and is worn in an 

 abnormal manner. Purchased. 



