214 DR. EMBLETON AND MB. ATTHEY ON THE 



half -mandible are differently arranged as to size and position 

 from those of the right half. 



The row of teeth begins in front, as in the other half -mandible, 

 with a small one ; next to this comes the largest tusk, behind 

 and internal to which is the largest depression, of a nearly cir- 

 cular outline ; next come two small teeth with a very narrow 

 depressed interval between them ; and below the former of these 

 it is that the alveolar border begins slightly to be deficient ; then 

 we have the second depression, followed by two teeth separated 

 by a depression broader than the last : immediately behind the 

 latter of these two teeth is a large and, as it were, double and 

 deep depression one inch and a quarter broad ; this is succeeded 

 by three tusks separated from each other by two large depres- 

 sions ; after the last of these three tusks is a broad depression 

 followed by a rather small tooth; lastly, behind this are two 

 other teeth still smaller, with very short intervals between them ; 

 and the fractured end of the bone occurs directly after the latter 

 of these teeth. 



The teeth (Plate IV., figs. 2, 3, 4, 5, 6). With the exception 

 of four on the right side of the cranium, three of which belong- 

 to the maxillary and one to the premaxillary, nearly half of the 

 teeth of the right ramus, and one of the left half are broken off, 

 as before stated. Their fracture is transverse, giving a circular 

 outline, within which can be roughly seen their beautiful laby- 

 rinthodont structure. Several other specimens, however, of 

 Loxomma have been found, of which the teeth are entire. 



The size of the teeth varies both in the upper and the lower 

 jaw, those of the vomerine plates and of the palate plates of the 

 maxillaries being much larger than those of the alveolar borders 

 of the maxillaries and premaxillaries ; the second tooth of the 

 left half of the lower jaw is much larger than any of the others 

 of that part ; the ninth, the seventh, and the eighth come next 

 in order of size, and occupy a middle position in the ramus. In 

 the right half, the second, eighth, and twelfth are the largest, 

 differing but little in size from each other, and the sixth is next ; 

 the twelfth is in advance of the middle of the jaw. The teeth 

 of the mandible are more deeply socketed than those of the 



