CETACEA. 205 



name of Blowers. As a large quantity of water passes into 

 their huge mouths along with their prey, some way was neces- 

 sary by which they could get rid of it j accordingly, it passes 

 through the nostrils by means of a peculiar disposition of the 

 velum palati, and is accumulated in a sac situated at the exter- 

 nal orifice of the cavity of the nose, whence, by the compres- 

 sion of powerful muscles, it is violently expelled through a 

 narrow opening on the top of the head. It is in this way they 

 produce those jets d'eau observed by navigators at so great a 

 distance. Their nostrils, continually bathed in salt water, 

 could not be lined with a membrane sufficiently delicate to 

 enable them to detect odours, and accordingly, they have none 

 of those projecting laminae, found in the nasal cavities of other 

 animals ; the olfactory nerve is deficient in several, and if there 

 be any which enjoy the sense of smell, it must be in a very 

 slight degree. Their larynx, of a pyramidal form, penetrates 

 into the posterior nares to receive air and conduct it to the 

 lungs, without compelling the animal to raise its head and 

 throat above the water for that purpose : there are no salient 

 laminse in the glottis, and the voice is reduced to a simple low- 

 ing. They have no vestige of hairs, but their whole body is 

 covered with a smooth skin, under which is that thick layer 

 of blubber abounding in oil, the principal object for which 

 they are pursued. Their mammse are near the anus, and their 

 fins are incapable of grasping. 



The stomach is divided into five and sometimes into seven 

 distinct sacs ; instead of one single spleen, they have several, 

 small and globular 5 those which are possessed of teeth, have 

 them all conical and alike ; they do not chew their food, but 

 swallow it rapidly. 



Two small bones suspended in the flesh, near the anus, are 

 the only vestiges of posterior extremities. 



Several have a vertical fin on the back, composed of a ten- 

 dinous substance, but unsupported by bone. Their eyes, flat- 

 tened in front, have a thick and solid sclerotica ; the teguments 

 of the tongue are soft and smooth. 



They may be again divided into two small tribes : those in 



