SPERM-WHALE, or CACHALOT (Physeter macrocephalus), the largest representative of the toothed whales, its length and bulk being about equal ,to, or somewhat exceeding those of the Arctic right-whale, from which, however, it is very different The Sperm- Whale (Physeter macrocephalus}.
in appearance and structure. The head is about one-third of the length of the body, very massive, high and truncated in front; and owing its size and form mainly to the accumulation of a peculiarly modified form of fatty tissue in the large hollow on the upper surface of the skull. The oil contained in cells in this cavity, when refined, yields spermaceti, and the thick covering of blubber, which everywhere envelopes the body, produces the valuable sperm-oil of commerce. The single blowhole is a longitudinal slit, placed at the upper and anterior extremity of the head to the left side of the middle line. The opening of the mouth is on the under side of the head, considerably behind the end of the snout. The lower jaw is extremely narrow, and * See Schiemann, op. cit., i. 81.
has on each side from twenty to twenty-five stout conical teeth, which furnish ivory of good quality, though not in- sufficient bulk for most of the purposes for which that article is required. The upper teeth are rudimentary and buried in the gum. The flipper is short, broad, and truncated, and the dorsal fin a mere low protuberance. The general colour of the surface is black above and grey below, the colours gradually shading into each other. The sperm-whale is one of the most widely distributed of animals, being met with, usually in herds or " schools," in almost all tropical and subtropical seas, and occasionally visiting the northern seas, a number having been killed around the Shetlands a few years ago. The food of sperm-whales consists mainly of squid and cuttlefish, but also comprises fish of considerable size. The substance called " ambergris," formerly used in medicine and now in perfumery, is a concretion formed in the intestine of this whale, and found floating on the surface of the sea. Its genuineness is proved by the presence of the horny beaks of the cuttles on which the whale feeds. The one representative of the genus Cogia is called the lesser or pigmy spermwhale, being only from 9 ft. to 13 ft. long.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)