^2 DESCRIPTION OF AN ENTIRE HEAD 



Breadth of malar bone just at orbit six inches. 



From posterior margin of tooth, to posterior margin of os palati, six inches. 



Loner Jaw. — The conformation of this is similar to that of the jaw belonging 

 to the Baltimore Museum, and described by one of the members of the Com- 

 mittee.* Its body is semicylindrical ; on the external face there is a deep round 

 groove, just above the symphysis, and which presents a rough foliated margin 

 on each side, considerably expanded. The chin presents no alveoli for tusks, 

 as in the Titracaulodon of Godman;t neither are there traces of such alveoli 

 ever having existed. 



The jaw contains one tooth on each side, with five denticules, each with two 

 points, all worn, and most so at their outer edge. In front of these teeth are re- 

 mains of the alveoli of the deciduous teeth preceding them. The teeth are 

 parallel; the left measures eight inches by four and a half — the right eight and 

 a quarter, by four and three-quarters of an inch. 



The length of this jaw is two feet six inches. The height of ramus fifteen 

 inches, and its breadth ten inches. The condyle is nearly transverse in its long 

 diameter, with a slight inclination of the latter inwards and backwards ; it 

 has no groove dividing its articular surface into an inner and outer portion, 

 as in the specimen in the Baltimore Museum, though there is a faint indication 

 of one. The coronoid process rises an inch and a half higher than the condyle ; 

 the latter measures five and a half inches in its long diameter. The angle of 

 the bone is rather well defined and obtuse. 



VERTEBRAE. 



The vertebrae, of which there are, as stated, specimens of each class, have a 

 conformation analagous to those of the Elephant. 



The first cervical vertebra (see Plate I., Fig. 2) measures fourteen inches 

 between the tips of the transverse processes, and ten inches from the anterior to 

 the posterior margin : immediately behind the superior oblique process there is 

 also a perfect canal for conveying the vertebral artery into the foramen mag- 

 num occipitis. 



* Description of Inferior Jaws of Mastodon, &;c. By Isaac Hays, M. D. Transactions of the 

 American Philosophical Society, Vol. IV., New Series. 



t Transactions of the American Philosophical Society, Vol. III., New Series. 



