186 
TRAVELS ON THE RIO NEGRO. 
{July, 
hind limbs. There is no distinct neck ; the head is not 
very large, and is terminated by a large mouth and 
fleshy lips, somewhat resembling those of a cow. There 
are stiff bristles on the lips, and a few distantly scattered 
hairs over the body. Behind the head are two powerful 
oval fins, and just beneath them are the breasts, from 
which, on pressure being applied, flows a stream of 
beautiful white milk. The ears are minute holes, and 
the eyes very small. The dung resembles that of a 
horse. The colour is a dusky lead, with some large 
pinkish-white marbled blotches on the belly. The skin 
is about an inch thick on the back, and a quarter of an 
inch on the belly. Beneath the skin is a layer of fat of 
a greater or less thickness, generally about an inch, 
which is boiled down to make an oil used for light and 
for cooking. The intestines are very voluminous, the 
heart about the size of a sheep’s, and the lungs about 
two feet long, and six or seven inches wide, very cellular 
and spongy, and can be blown out like a bladder. The 
skull is large and solid, with no front teeth ; the ver- 
tebrae extend to the very tip of the tail, but show no 
rudiments of posterior limbs ; the fore limbs, on the 
contrary, are very highly developed, the bones exactly 
corresponding to those of the human arm, having even 
the five fingers, with every joint distinct, yet enclosed in 
a stiff inflexible skin, where not a joint can have any 
motion. 
The cow-fish feeds on grass at the borders of the 
rivers and lakes, and swims quickly with the tail and 
paddles ; and though the external organs of sight and 
hearing are so imperfect, these senses are said by the 
