Ill 



PHTSETEB mcnocEpHALUs, 1 Linnaeus. The Sperm or Spermaceti 

 Whale. 



Synonyms Physeter macrocepJialus, Linn., 0. Fabr., Shaw, Bell, 

 Flower, Murie. 



Catodon macrocephalus, Lacep., Gray, S. & ~W., p. 202, Suppl., 

 p. 59. 



Catodon australis, Gray, S. & "W., p. 206. 



Meganeuron Krejftii, Gray, S. & W., p. 387, Suppl. 59. 



Teeth W to -fr- on each ramus, large, conical, often worn down. 



The above generic characters apply to this species, and which I 

 believe to be the only one of the true sperm whale. 



The massive head of the living animal is truncated in front ; the blunt 

 extremity, which projects considerably beyond the lower jaw, is com- 

 posed of a thick, fatty substance, called by seamen the junk : this junk 

 is at all times large, but in a large whale it weighs between two and 

 three tons, and serves from its elasticity to act as a buffer to lessen the 

 effect of sudden concussion accidentally received when the huge mass is 

 in rapid motion. 



The great weight of the bones of the skull is efficiently buoyed up, 

 partly by the light material of which the junk is composed, but prin- 

 cipally by the large quantity of oil, of course of much lesser specific 

 gravity than the surrounding water, pent up in the cranial reservoir, 

 and usually estimated at from three to five hundred gallons ; a fact well 

 illustrated by the few lean individuals occasionally met with at sea, 

 who express by their actions a general want of buoyancy, but more 

 especially in the head. 



The mouth is large, lined throughout with a pearly white membrane, 

 and terminates in a throat sufficiently large to allow a free passage to 

 the body of a man. The eyes are small, and placed over the angle of 

 the mouth. 



Under the outer skin lies a layer of yellowish-coloured blubber, 

 termed by whalers the blanket, which varies in thickness from 8 to 14 

 inches, the breast, dorsal hump, and upper margin of the tail affording 

 the thickest, and from which is obtained the sperm oil of commerce. 

 The more valuable product, the spermaceti, is almost wholly abstracted 

 from the cavity on the crown of the head, and frequently amounts to 

 ten large barrels in the crude state. 



The colour of the body along the upper surface is very dark, occa- 

 sionally black, and fades into a lighter tint on the sides and belly, 

 becoming silvery-grey under the cheat. 



1 fuutp6s, long, and Kpa\i'i, the head. 



