371 
which was, however, much shorter and less acute than in the elephant ; 
that the posterior angle, although obtuse, is defined, and not rounded 
off* as in the elephant ; and that the arms or branches of the jaw, 
formed of the condyloid and coronoid processes, and their bases, are 
shorter and flatter than in the elephant, as is required by the peculiar 
form of the upper jaw. 
No perfect specimen of the skull of this animal has been hitherto 
found ; but, from the fragment in the possession of M. Camper, and 
from that of Mr. Peale, it appears, 1. That in the mastodon the grinders, 
in the upper jaw, diverge forwards; whereas, in the common elephants, 
they converge more or less ; and in the fossil elephant, or mammoth 
of the Russians, they are nearly parallel. The hog and the hippopo- 
tamus approach the mastodon a little in this respect. 2. The bony 
palate extends considerably beyond the last tooth. The Ethiopian sow 
is the only herbivorous animal which resembles the mastodon in this 
respect. 3. The pterygoidal apophyses of the palate-bones are of a 
thickness unparalleled among the quadrupeds. 4. The notch before 
this apophysis has some agreement with that of the hippopotamus, which 
is, however, narrower. 5. That there is no trace of any orbit in the 
zygomatic arch ; but that where the orbit occurs, in the elephant, is 
a large mass of bone ; so that the eye must have been placed much 
higher in this animal than in the elephant. 6. That the maxillary bones 
have a less vertical elevation than in the elephant. 7- That, hence, the 
zygomatic arch is less raised behind, agreeable to the conformation of 
the lower jaw ; and, of course, the position of the ear varies from that 
which takes place in the elephant. 8. From this proportion results the 
difference in the situation of the occipital condyles in the two animals ; 
they being raised considerably above the level of the palate in the ele- 
phant, and nearly on the same level with it in the mastodon. With 
respect to the large cells, from which proceeds so great a degree of 
thickness in the skull of the elephant, there seems to be every reason for 
supposing that these existed in a similar manner in this animal. Of 
