CETACEA. 211 



portion^ which is altogether owing to an enormous develop- 

 ment of the bones of the face. 



FHYSETER, Lin. 



The Cachalots(l) are Cetacea with a very voluminous head, exces- 

 sively enlarged, particularly in front, in whose upper jaAv there is 

 neither whalebone nor tooth, or if any, very small, and not projecting; 

 the lower jaw, narrow, elongated, and corresponding to a furrow in 

 the upper one, is armed on each side with a range of cylindrical or 

 conical teeth, which, when the mouth is closed, enter into corres- 

 ponding cavities in the upper jaw. The superior portion of their 

 enormous head consists almost entirely of large cavities, separated 

 and covered by cartilages, and filled with an oil which becomes 

 fixed as it cools, well known in commerce by the name of spermaceti, 

 a substance for which they are principally sought; the body not 

 having much fat, and consequently yielding but little oil. These 

 cavities, however, are very distinct from the true cranium, which 

 is rather small, is placed under their posterior portion, and contains 

 the brain as usual. It appears that canals, filled with this sperma- 

 ceti, or adipocire as it is called, are distributed to several parts of 

 the body, communicating with the cavities which fill the mass of the 

 head; they even ramify through the fat or blubber that is found 

 beneath the skin. 



The odorous substance, named ambergris, appears to be a con- 

 cretion formed in the intestines of the Cachalot, particularly during 

 certain states of disease, and it is said, chiefly in the caecum. 



The species of the Cachalots are far from being well as- 

 certained. That which appears to be the most common, the 

 macrocephalus of Shaw and Bonnaterre, (Lacep. X)(2) in lieu 

 of a dorsal fin, has a mere callous prominence. There are from 

 twenty to twenty-three teeth on each side of the lower jaw, and 

 some small conical ones hidden beneath the gum in the upper 

 one. Its spiracle is single, and not double as in the greater 

 part of the other Cetacea ; neither is it symmetrical, but is di- 

 rected towards the left, and terminates on that side, on the front 

 of the muzzle, which is truncated. (3) In addition to this, it is 

 said that the left eye is much smaller than the other, and that 



(1) Physeter as well asphysalus, signifies blower. Cachalot is the name used by 

 the Biscayans ; from cachau, which in the Cantabrian dialect means tooth. 



(2) It is not the macrocephalus of Linnaeus. 



(3) We have verified on two crania this want of symmetry in the spiracle, an- 

 nouncfed by Dudley, by Anderson and by Swediauer, which inclines us to credit 

 the inequality of the eyes mentioned by Egcde. 



