14 



THE WHALEBONE WHALES. 



flattened, and the crest on the back part of 

 the head is continued forwards on the edges 

 of the upper jaw so as to form a wide basin. 

 There is no resemblance at all between this 

 skull and the head of the living animal. The 

 enormous cylinder which forms the latter is 

 in fact composed of sinewy tissues forming 

 large cells filled with a fat, which at the tem- 

 perature of the animal is fluid, but which in 

 the solid form is known as spermaceti or c€tm. 

 It is chiefly for the sake of this fat that the 

 sperm-whale is pursued. A large male may 

 yield as much as twelve tons of spermaceti, 

 for the valuable substance is contained not 

 only in the cells in the head, but in a long 

 cellular tube which runs along the back. The 

 dentition is peculiar. The upper jaw has 

 only rudiments of teeth during embryonic 

 life, but the lower jaw is armed with large, 

 strong, conical teeth, which are at first sharp- 

 pointed but afterwards get blunted, and which 

 are received into corresponding pits in the 

 upper jaw when the creature shuts its mouth. 

 The sperm-whales, of which there are pro- 

 bably two species, one living in the southern 

 seas the other in those of the northern hemi- 

 sphere, appear to feed exclusively on cuttle- 

 fishes. Now that we know that enormous 

 cuttle-fishes, gigantic specimens of which are 

 occasionally, though rarely, cast on our shores, 

 are found in almost all seas, this kind of food 

 does not appear so incompatible with the size 

 of the creature as it once did. Though it is 

 chiefly for the spermaceti, as has already been 

 stated, that the sperm-whale is pursued, that 

 is not the sole product of commercial value 

 that it yields. Besides the blubber, which is 

 not very abundant and yields only a mediocre 

 oil, this whale supplies us also with the am- 

 bergris which is so highly esteemed in the 

 East as an article to burn as incense and for 

 use in perfumery, and which is not only 

 obtained directly from the animal itself, but is 

 likewise found floating on the waves in clumps 

 about the size of one's fist. It is probable 

 that these fatty masses are formed either in the 



bladder or the genital glands of the male. 

 The teeth are also used for the same purposes 

 as ivory. 



The chase of the sperm-whale is difficult 

 and dangerous: difficult, because the animal 

 avoids man more carefully than any other 

 cetacean, and remains, on diving, much longer 

 under the water; dangerous, because, when 

 wounded, the creature defends itself with 

 courage, attacks the boats and even the ships, 

 endeavouring to capsize them or to pierce 

 their sides. Numerous cases have been 

 known in which ships have had their sides 

 shattered by sperm-whales which dashed 

 against them with the utmost rapidity, giving 

 a shock with their heads like that inflicted by 

 the ram of an ironclad. 



THE WHALEBONE WHALES 



(MYSTICETE). 



The members of this group are much less 

 numerous than the toothed whales. The 

 head, which is always massive, relatively very 

 large and broad, has a weak lower jaw of 

 elliptical outline, a mouth with an enormous 

 cavity, from the roof of which hang down the 

 horny plates which yield the whalebone, while 

 the lower part of the cavity is filled with an 

 enormous tongue composed almost entirely 

 of fat. The halves of the lower jaw are 

 separate, connected only by a rather loose 

 ligament. In those countries in which the 

 whale-fishery is carried on these bones of the 

 lower jaw are used as gate-posts at field-gates. 

 In the rest of their organization the whale- 

 bone whales do not differ very much from the 

 toothed-whales. They all have double blow- 

 holes, the halves of which are separated by a 

 narrow partition. 



We have already said that in the embryo 

 numerous teeth which never cut the gum are 

 concealed in a continuous groove running 

 round the jaw. These little teeth, similar in 

 form to those of the sperm-whale, become 

 absorbed as the animal grows. 



