1869.] HULKE STEITEOSAUETJS EOSTRO-MINOR. 393 



like manner, the lower ones coursing parallel to this border, while 

 the upper lines radiate towards the coronoid process. The angular 

 bone forms the lower half of the hindermost 16 inches of the ramus, 

 and completes the posterior extremity. It composes the whole lower 

 border of the ramus for about 25 inches, and it is also visible on the 

 inner surface, below the articular bone, from which in this situation it 

 is marked off by a suture, which, further forwards, a couple of inches 

 in front of the salient anterior internal angle of the articular bone, 

 becomes lost in the matrix. In the outer surface a conspicuous 

 suture, nearly straight for the first 9 inches from the posterior ex- 

 tremity, and then curving downwards for the next 15 inches, sepa- 

 rates the angular bone from the dentary and surangular bone above 

 it. The anterior two-thirds of the angular bone are also longi- 

 tudinally striated ; and the uppermost striae run out obliquely at the 

 upper border of the bone, which helps to increase the distinctness of 

 the suture between it and the surangular. On the inner side, the 

 anterior internal angle of the articular bone projects strongly 3 inches 

 above the lower border of the ramus, and nearly 6 inches from its 

 posterior extremity ; its anterior margin descends at first almost 

 vertically, and then curves forwards to the suture with the angular 

 bone. In front of this the inner surface is hidden for nearly 4 

 inches by large splints of bone lying athwart it, which are, I think, 

 pieces of the upper jaw*; and for 6 inches in front of these it is 

 much defaced ; but beyond this, to the dental part, it is smooth, 

 and channelled by a broad, shallow, longitudinal groove. The sple- 

 nial bone is wanting. 



The piece of the lower jaw lent me by J. C. Mansel, Esq., consists of 

 7 inches of the anterior extremity of the right half. The lower and 

 upper lines meet in rather a blunt point. The outer surface, trans- 

 versely convex, is beset with a few vascular foramina below the two 

 first alveoli. The inner, vertical surface is scored with marks of the 

 symphysial suture. The upper surface is horizontal and flat, rising 

 slightly towards the inner border ; its outer third is pierced by the 

 openings of six sockets, from the four last of which fully grown teeth 

 protrude. The sections which Mr. Mansel has most kindly allowed me 

 to have madef, show clearly the loose implantation of the long tooth- 

 fangs in capacious alveoli, which have a forward and outward in- 

 clination that gives a corresponding slant to the teeth. The alveolar 

 apertures in the border of the dentary bone are quite distinct from one 

 another. They are here separated from each other by very evident 

 unbroken partitions, which, however, are less complete in the in- 



* These splints have been further exposed since the above account was written ; 

 they are portions of both maxillge crushed and retroverted, so that the front 

 end overhangs the posterior extremity of the ramus of the lower jaw. The 

 nasal bones are absent ; but the groove into which they were received reaches 

 forwards for a considerable distance on the upper and inner edge of the max- 

 illary bones. 



t For getting these sections made I am under great obligation to Mr, Ethe- 

 ridge. 



