OF THE CLASS MAMMALIA. 301 



mous animals live generally not on fishes, but on small mol- 

 lusca, Crustacea, zoophytes, and generally the lowest marine 

 animals. They swim rapidly, and are timid and fearful ; 

 hence they are easily destroyed by the whalers. 



There are several species of whalebone whales, but that 

 which is most sought after, by reason of the length of whale- 

 bone and the abundance of blubber it possesses, is the Green- 

 land whale, or whale of commerce ; formerly perhaps abun- 

 dant in the European seas, but now driven by persecution to 

 take refuge in the Northern and Polar Seas. It has no dorsal 

 fins. 



Fig. 278. The Whale of Commerce ; Balaena Mysticetus, or Greenland 

 Whale. 



The cachalot or sperm whale has teeth only in the lower 

 jaw, and no whalebone. The enormous size and singular form 

 of the head of the cachalot is owing to a vast collection of oil, 

 which, when cold, becomes fixed, and forms the substance called 

 spermaceti. It is situated in cavities occupying the upper 

 part of the face and head. These cavities are supported late- 

 rally by largely developed upper jaw-bones, which give to the 

 skeleton of the head a very peculiar appearance. 



The whale fishing, an important branch of commerce, and 

 in which the boldest sailors are trained, was at one time in 

 the hands of the Basques, but now almost exclusively belongs 

 to the English and Americans. The vessels proceed either 

 north or south. The northern fishery has for its object the 

 capture of the mysticetus, or Greenland whale. In the stormy 

 seas of the North, the whaler attacks the whale with the 

 harpoon. The blubber is found immediately beneath the 



