Dr. H. Burmeister on a new Cetacean. 95 
alittle curved backwards ; the mouth on each side is 21 centime- 
tres in length, and the small eye is 22 centimetres distant from 
the posterior angle of the mouth. The ear is a very small open- 
ing, 1 millim. in breadth, situated 10°5 centim. behind the eye ; 
the aperture of the nose is a transverse arched fissure, 10°5 centim. 
in breadth, on the top of the head, 45 centim. distant from the 
point of the snout. There are two remarkable diverging plaits, 
24 centim. long, on the throat ; two small fins, 35 centim. long, on 
each side of the breast, about half a metre distant from the eye ; 
and another smaller, of a curved shape and 17 centim. high in the 
posterior part of the back, about 2 metres distant from the 
nostril. To this fin corresponds, in the under part of the body, 
the position of the posterior openings, the sexual aperture being 
a little before the fin, and the anal aperture a little behind it. 
Both are longitudinal fissures, the first 16 centim. broad and 
the second 9; at the commencement of the second are seen two 
other small fissures of 3 centim., one on each side, which indicate 
the teats. As far as these apertures and as the posterior fin the 
body is round; but beyond them, where the tail begins, its 
shape changes to a compressed lamina with sharp edge above as 
well as below. Thus the tail diminishes quickly, descending at 
first, and afterwards ascending in a direction inclined backwards 
until the point, where there is a large horizontal fin of a metre in 
breadth, semilunar in shape, but without incision in the middle, 
this part being little more prominent than those on either side, 
near the central portion of the tail. This is aremarkable feature 
in the animal, as likewise the upward inclination of the tail. The 
whole body is ofa clear grey colour, a little yellowish, but darker 
on the back and lighter on the stomach; the fins are darker, 
almost black, and the large fin of the tail has an irregular white 
spot underneath. 
In studying the internal parts I began with the mouth, seeking 
for teeth, but not meeting with any; the gum consisted of a 
narrow callus, a little raised on each side of the mandible, rather 
wider in the lower one, especially at the point of the mandible. 
Opening this callus with my anatomical knife, I was much 
surprised to find, inside of the gum, a large number of very smal! 
teeth, each enclosed in a little bag, to which it was fastened at 
its two points, as well above as below. These teeth are about 3 
to 5 millim. long, of conical shape, and slightly enlarged at the 
upper part. I counted 25 teeth in the gum on each side of the 
upper mandible, and from 30 to 32 in the lower. There are 
besides two very large teeth at the point of the lower jaw, of 
very pointed conical shape, also imbedded in the gum. These 
two teeth are found in the same manner in the genus Hyperoodon, 
as well as those in the gums; but as the skull is without the 
