21 



thus a wide canal where the Eustachian tube takes its origin. 

 Behind, this canal is closed, and assumes a somewhat bilobed 

 form at the place where it becomes confluent with the posterior 

 j)art of the labyrinth, by means of a rugose bony apophyse, to 

 which the suspending cartilage is attached. 



or THE SPINAL COLUMN. 



The spinal column in our specimen consists altogether of 

 forty-four vertebrae, i.e., if we consider the cervical vertebrte to 

 be only two. But these in fact are seven, the first or atlas being 

 free, and the other six* much compressed, being anchylosed 

 together, as is manifested by their distinct ridges, which Cuvier 

 long since pointed out in his Loudon Skeleton, Oss. Fo.ss. pi. 22, 

 fig. 13. 



The dorsal vertebrse, or those to which the ribs are attached, 

 are ten in number, having the vertical spinous processes inclined 

 backwards, and increasing in length from the first to the last. 

 They have also short transverse processes on each side, and the 

 spinous process has an anterior articular, which being bifid, serves 

 for locking one vertebra into the other, by receiving the inclined 

 edge of the vertical apophyse of the preceding vertebrae into its 

 bifurcation. 



The next eight or lumber vertebrae, have their spinous pro- 

 cesses wider at the summit than at the base. These are also 

 more oblique and elongated than in the dorsal vertebrae, and 

 their articulars rise gradually on their front edge, as in the 



* In the genus Ilyi^troodon and most of the Delpldnidoj all the seven 

 cervical vertebne are soldered together, which occurs likewise in the true 

 whales. But in the bottlenosed dolphin, as well as the dolphin of the 

 Ganges (Plalanista, Gangetica of Cuvier), it is stated by Cuvier that all the 

 cervical vertebrce are free ? What is singular is, that in the Rorquals, at 

 least in the Cape Rorqual, the only cervical vertebra soldered together are 

 the axis and its following one ; all the rest being quite free. In the order 

 of Cetacea it is to be observed that the cervical vertebrte vary much in 

 structure. For instance, Daubenton and Cuvier both state that the manati 

 has only six such vertebrae. 



