678 



4241. A vertically and longitudinally bisected skull of an old female Otter (Lutra 

 vulgaris). 



The sutures are obliterated. The cranium is shorter, especially at the rhinencephalic part, 

 than in the male. The surface of the cranium to which the temporal muscles are attached is 

 rugged. The bony tentorium terminates upon the petrosal above the small pit for the cere- 

 bellar appendage. The cranial walls are thin, without diploe. The impressions of the con- 

 volutions are strongly marked. 



Presented by Henry Cline, Esq. 



The following, to No. 4262 inclusive, are parts of the same skeleton of the Otter (Lutra 

 vulgaris) : 



Hunter ian. 



4242. The skull. 



4243. The atlas. 



The anterior articular cavities are completely disunited. The vertebral artery perforates 

 the transverse process horizontally, and slightly grooves it anteriorly as it ascends to perforate 

 the neural arch. 



4244. The dentata. 



A tubercle is developed above each of the posterior zygapophyses. 



4245. The fourth cervical vertebra. 



The tubercle upon the posterior zygapophysis is developed into a ridge. 



4246. An anterior dorsal vertebra. 



4247. A lumbar vertebra. 



4248. The two anterior or normal sacral vertebrae. 



The spinous processes are better developed than in any of the other Mustelidte. 



4249. An anterior caudal vertebra. 



4250. The first thoracic rib. 4251. The fifth thoracic rib. 



