Osteology of Loxomma Allnianni. 51 



ment of this description, 2 or 3 feet apart and not far from the 

 skull ; they are of the proper size to fit it, and most probably 

 belonged to it. 



The right half (fig. 2, half the natural size) is almost perfect ; 

 its alveolar border is quite so ; it exhibits the teeth in a 

 beautiful state of preservation ; and its exterior is covered with 

 the peculiar reticular sculpture. It measures nearly 14^ inches 

 in length, and at the widest part, which is about 4 inches from 

 the posterior end, 2|- inches in width ; from this point it 

 tapers gradually to the anterior end, where it is perfect and 

 little more than an inch in width. 



A narrow groove can be observed to run nearly the whole 

 way along the inferior border of the specimen, beginning below 

 the articular projection ; whether this is a mucous groove, or 

 what its signification is, is not easily determined. 



The inferior margin is slightly convex ; the upper or 

 alveolar somewhat concave, with a slight eminence in front 

 supporting the first large tooth. The anterior end terminates 

 in a symphysis which is rather deep, and, as seen in another 

 specimen, extended downwards and backwards, its depth 

 being If inch, its breadth at top f inch, below which it 

 lessens to \ inch. 



Near the posterior end the outer layer of the bone in our 

 specimen is for a short space altogether wanting ; but beyond 

 this the articular end is well preserved, at least at the outer 

 side. From this specimen, and from another in Mr. Atthey's 

 possession, it can be discerned that the articular sm-face was a 

 rather deep, transversely elongated, and smooth groove, rather 

 more elevated in the middle than at the ends, for the reception 

 of the condyle of the uj)per jaw, which was similarly elongated, 

 and whose ends were gently raised above the level of the 

 middle. 



In another specimen in Mr. Atthey's collection, larger 

 than the subject of this paper, the length of the articular 

 groove on the mandible is If inch, the breadth \ inch, and 

 the greatest depth \ inch. The posterior border of the articular 

 surface curves upwards and forwards, so that the joint, though 

 it was not interlocked, must have been pretty secure. The 

 articular part of the jaw projects outwards from the plane of 

 the ramus half an inch. The inner surface is not visible in 

 this, but can be well seen in the other half-mandible. 



It will be observed that the teeth in the right half are all 

 entire, whilst those of both sides of the maxilla and, as will 

 be seen in the sequel, those in the left half-mandible are all 

 broken off short. The difference is thus accounted for : in 

 the matrix they were all entire : but on this beino- broken up, 



4* 



