3i6 TYPES OF ANIMAL LIFE. 



than one-third of this is occupied by its enormous head, 

 the vast size of which is due to the great jaws which 

 enclose what one might call an immense cavern con- 

 taining the tongue and a quantity of horny plates — the 

 so-called " whalebone." The upper jaw-bone is very 

 narrow from side to side, but much arched from before 

 backwards, while the lower jaw is greatly arched outward 

 on either side. The upper lip is rudimentary, but it is 

 met by a prodigious lower lip which stands up stiffly 

 with a very convex margin from before backwards. Just 

 behind the mouth is the small eye, close behind which 

 -again is the scarcely perceptible opening of the ear. The 

 nose opens near the summit of the head by two crescentic 

 apertures which can be opened or closed at wiU. A 

 little behind and below the eye, the fore-hmb, or paddle 

 juts out. This has no power of motion except at the 

 shoulder-joint, although inside it are bones representing 

 those of the upper and forearm and of the five fingers of 

 man and other pentadactyle beasts. But whereas in 

 man and all such beasts the number of bones in every 

 finger never exceeds three, here there are five in what 

 represents the middle finger, and four in the skeleton 

 of the digit on either side of it. At the hinder end of 

 the body is a tail-fin in the form of two lateral pointed 

 expansions of skin, supported by a dense fibrous substance 

 within. Though no trace of any posterior limb is visible 

 externally, there is, deep in the interior of the animal, a 

 bone, only about eight inches long, which probably 

 represents the thigh bone and bears at its extremity a 

 small ossicle, which may be regarded as a rudiment of 

 the shin bone. The former of these two bones is 

 attached to a rudimentary representation of the pelvis, 

 which exists here as well as in the mermaids. Although 

 the neck is so short as to be imperceptible externally. 



