SPERM WHALES AND BOTTLE-NOSED WHALES 267 



on the total stock of Sperm Whales, it is interesting to note 

 the indication given by the figures of the abundance of these 

 whales in high latitudes. 



Genus Kogia. 

 THE PIGMY SPERM WHALE [Kogia breviceps). Fig. 68. 



The Pigmy Sperm Whale or Lesser Cachalot, notwithstanding 

 its small size compared with Physeter, is closely related to the 

 great Sperm Whale. It agrees with the latter animal in 

 having the single blowhole situated a little on the left side 

 of the head, in the possession of a spermaceti organ, in 

 having functional teeth restricted to the lower jaw, and in 

 numerous osteological characters which need not be mentioned 

 here. 



The name Kogia is said to be the latinized form of the word 

 " codger ", and breviceps — short-headed — the trivial name of 

 the best known species, refers to a character common to all the 

 forms of this genus which, at one time or another, have been 

 given specific rank. The head of the Sperm Whale, it will be 

 remembered, constitutes one-third of the total body length, 

 whereas that of the Pigmy Sperm is about one-sixth. The 

 rostrum 01 beak portion of the skull is not elongated in Kogia 

 as in Physeter and, associated with this, the external outline 

 of its head is not unlike that of the Common Porpoise. It 

 differs from the Porpoise, however, in that the lower jaw, 

 instead of extending forwards to the tip of the snout, ends 

 several inches behind it. Indeed, the shape and position of the 

 lower jaw recall to some extent that of a shark. 



The external form of the body is like that of an ordinary 

 dolphin ; passing backwards from the roughly conical head 

 the outline merges into that of the trunk without perceptible 

 break. The greatest circumference is in the region between 

 the flipper insertion and dorsal fin which, in Kogia, is well 

 defined and well developed, not at all like the " hump " found 

 on the Sperm Whale's back. This fin is situated midway 

 along the body, and is falcate in form like that of the Common 

 Dolphin. The body tapers from just in front of the dorsal fin 

 to the stock of the tail which, before widening out to the tail 



