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 ridof it; accordingly, it passes 
through the nostrils by means of a paetidr 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 sufliciently delicate to 
enable them to detect odours, and accordingly, they have none 
of those projecting lamin 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 
laminz 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 mammez 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 ; those which are possessed of teeth, have 
them all conical and alike; they do not chew their oe but 
swallow it rapidly. 
Two small bones suspended i 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 maybe again divided into two small tribes: those in 
