93 



400. A scries of vertebra; from the Galftu eommtmu. Mtu. Brit. 



401. Four caudal vertebrae of the Gnleiu commit nit. Mm. Brit. 



402. The jaws of a Shark (Galen* ferox). Mtu. Brit. 



403. The jaws of a Shark (Gafau ferox). 



Not any of the erect series of teeth are broken in this specimen, but the place* of attach- 

 ment of the shed teeth are visible exterior to these. The form of tooth characteristic of the 

 genus (ialeut is better adapted to resist fracture, the base being broader and stronger, than 

 in the Carchariat. 



MK*. Brit. 



404. The upper and lower jaws of the same species of Galetu. Mtu. Brit. 



405. The upper and lower jaws of a smaller individual of the same species of 



Gains. Huntrriatt. 



406. A portion of one of the jaws of a Galen*/erot, showing the modifications of the 

 characteristic form of the teeth in this genus, observable in those situated at 

 the middle and at the extremities of the jaw. Hunteria*. 



407. A section of one of the jaws of a Galeusferox, showing three of the vertical or 

 successional scries of teeth. 



The middle series consists of one tooth, erect and in use at the margin of the jaw, and four 

 recumbent teeth attached to its posterior surface. They are covered by a fold of the buccal 

 membrane in the recent fish, and show progressive stages of development as they approach 

 the teeth in use. 



Pretented by Prof. Owen, F.R.S. 



408. The skull and bodies of the anterior vertebra? of the trunk of the Blue Shark 



( Car chariot glaiunu) . 



The pillars of the rostrum, the cartilaginous cavities for the nasal capsules, the wide 

 anterior t'untanclle, the pterygoid arches confluent at both ends with the base of the skull, 

 and other characteristics of the skull of the Shark, are well shown in this specimen. The 

 anterior vertebrae are, as it were, clamped to the skull by the backward extension on each 

 side of firm cartilaginous processes from the occiput. On the summit of the occiput are the 



