402 GILPIN OBSERVATIONS ON SOME FOSSIL BONES. 



measures only half an inch. From studying, what of course must 

 be a very broken series of the remains of transverse processes, we 

 can make out a general principle, that as in the dorsal they spring 

 lower and lower from the neural arch, so also in the lumbar, 

 they spring lower and lower from the body of the vertebra until 

 they become lower than the centre of the vertebra itself. Thus 

 the neural arch with the spinal cord runs slightly oblique to, 

 rather than parallel with, the line of transverse processes. Of the 

 four remaining caudal vertebra, two only have a small process to 

 mark the transverse process, but they all have a slight depression in 

 the upper surface, making the floor of the neural arch, and chevrons 

 from the lower surface. These chevrons though much decayed, 

 have remains of a double process, projecting like two horns from 

 the anterior articulating surface of the vertebra, into which, evi- 

 dently, a single process from the posterior articulating surface of 

 the vertebra next preceding it had fitted. The smallest caudal 

 vertebra measured one and one-half inches in length, with the 

 long diameter two and one-half inches. There were many frag- 

 ments of bones composing the base of the skull, with marks of 

 sutures, a petrous portion of the bones of the ear, and about one- 

 half of the right jaw, the latter well preserved. 



This frao^ment measured three and one-half inches in lens^th and 

 two inches in depth. There were three large neural foramena and 

 the symphasis showed that it was blunt or round, and that there 

 were small teeth about half way down the jaw from it. There are a 

 few fragments of spinous processes which show that at their anterior 

 roots were processes pointing forward. A fragment of the sternum 

 remains, nine inches long, irregularly triangular, and having on its 

 left side very deep marks of articulation with the ribs. It is slightly 

 convex on its external surface, and slightly concave on its internal 

 surfaces, and was evidently much longer. The fragments of both 

 scapulas remain. They are unevenly convex on the external, 

 unevenly concave on the internal side, but very flat, with no spinal 

 ridge. The acromion and coracoid processes are well developed, 

 but upon the same plane as the large humeral articulating surface. 

 From the fragments, it seemed that it had resembled a pole-axe, the 

 head being the cavity for the humerus. The humerus is very com- 



