1468 Cetacea. 



especially towards their extremities. The seven first two-headed 

 ribs are joined to the sternum, which is sub- cartilaginous, and the 

 three others or false ribs have the apex free. The sternum, which is 

 not yet ossified in all its parts, is formed of seven distinct bones, the 

 superior one of which is the largest, it is truncate superiorly, and 

 forked posteriorly ; the following sternal bones go on gradually de- 

 creasing in size, and have a square shape with a rounded notch on 

 their anterior and posterior margins. On the inferior surface of the 

 first sternal bone are two rounded depressions. 



The eight first costal vertebrae have no lateral processes, but the 

 two last are furnished with them. 



The eleven lumbar vertebrae have the same shape as the two last 

 costal ones, their lateral processes are wide, long, and directed for- 

 wards. 



The sacral vertebrae and six first caudal vertebrae have both supe- 

 rior or spinal and inferior processes, the seventh and eighth caudal, 

 only spinal ones, and the remainder have no processes of any kind, 

 and are more or less globular. These last go on diminishing gradu- 

 ally in size until the terminal one, which is smaller than a pigeon's 

 egg. The inferior process of the sacral vertebrae is angularly elbowed. 

 The seventh caudal has a small rudimentary inferior process placed on 

 the inferior posterior margin of the vertebrae. 



Limbs, 8$c. Metacarpus wanting or cartilaginous. Scapular ra- 

 ther small, its coracoid process is double the size of the acromion, and 

 slightly curved : humerus shorter than radius : radius and cubitus 

 tubercular, and very approximating : bones of carpus placed in two 

 rows, there are six of them, of which the two medial are the largest: 

 upper finger formed of two phalanges, second of four, third of four, 

 fourth of five, and fifth of one phalanx. 



Hyoid apparatus formed of five bones, of which the middle one is 

 pentagonal, and the others depressed and lengthened, two of them 

 being double the size of the others. Two small ischionian bones ex- 

 isted suspended in the flesh, but they had been lost. 



Dimensions of Skeleton. 



Total length of head 



Apex of inferior maxilla to auditory canal 

 Crest to the atlas 



It. 



in. 



line. 



o 















18 











5 



5 



