158 NOTES ON THE ANATOMY OF A SEAL—SOMMERS. 
and phalangeal bones are developed out of proportion to the 
bones of the forearm, taken together they havea much greater 
length, the flexors and extensors of the wrist, &e., are short and 
thick, the tendons are long and well developed. 
The inferior extremities of the seal are also confined in the 
general integument, the bones being shortened and otherwise 
moditied as in the anterior extremities, yet every bone is present 
as in man, the gluteal muscles are short and well developed, but 
it is evident from dissection that the other muscles of the hind 
limbs in the seal are not so well developed as the corresponding 
organs in the anterior members, the articulation of the femoral 
bones, and the insertion of their muscles are such that the infer- 
jor extremities are twisted so that the tibial bones are external 
to the fibule, owing to this the palmar surfaces of the feet 
become opposed to each other in a position similar to that 
which can be produced in the hands of man by the partial rota- 
tion of the radius upon the ulna. 
The phalangeal bones of the feet are longer than those of the 
forelimb, the claws are not so large, the tegumentary covering 
broader and looser allowing great freedom of movement in these 
parts which are readily observed to be specially adapted for pro- 
gression in the water, while comparatively useless for the same 
purpose on land. The tibize and fibulee were free. 
Opening the thorax, the viscera were examined; larynx and 
trachea same as in other animals, the rings of the latter being, 
however, complete; right lung, upper lobe distinct; middle and 
lower imperfectly divided or marked off from each other; left 
lung distinctly two-lobed; weight of lungs and heart, 1} Ibs. ; 
heart large, notched at the apex, denoting imperfectly the septum 
between the ventricles, four-chambered ; the foramen ovale open, 
Eustachian valve not more marked than in the heart of adult 
human subjects: ductus arteriosus not present. The aorta gave 
off separate subclavian and carotid arteries for either side. The 
anatomy of the vascular system in other respects differs not from 
that of man. 
Of the abdominal viscera, the stomach was large, having the 
bagpipe shape of the organ in carnivora, being also simple; it 
