112 
CETACEAN GALLERY. 
is Hyperoodon rostratus, of which are exhibited a complete skeleton 
of an adult female, taken at Whitstable, Kent, in 1860, and the 
skull of a very old male from the Orkneys, in wliich the bony 
crests, rising on each side from the uj)per jaw, have attained such 
an extraordinary development, that it was long supposed to be the 
type of a distinct species, called H. latifrons. It has, however, 
now been shown, that while in the young of both sexes the crests 
are quite small, in the female they remain permanently of the size 
shown in the skeleton, and in the male they gradually increase 
as age advances. This animal is an inhabitant of the northern 
parts of the Atlantic Ocean ; and as it yields both spermaceti and 
oil, equal in value to that of the Sperm-Whale, it is now the object 
of a regular “ fishery.^^ 
The southern representative of this species (H. planifrons) is as 
yet only known from the water-worn and rolled skull from Western 
Australia exhibited near the northern specimens, and the extent of 
its range still remains to be discovered. 
Family Platanistid^e. 
On the left side of the door, near the first window, is a Case 
containing a stuffed specimen, skeleton, and several skulls of the 
very curious freshwater Dolphin of the rivers of India [Platanista 
gangetica). It has never been found in the open sea, but is exten- 
sively distributed throughout nearly the whole of the river-systems, 
not only of the Ganges, but of the Ilrahmaputra and Indus, 
ascending as high as there is water enough to swim in. The eyes 
are exceedingly small and imperfect in structure, and it appears to 
be quite blind. It feeds on small fish and Crustacea, which it 
gropes for with its long snout in the muddy water at the bottom 
of the rivers. The blowhole, as may be seen in the stuffed spe- 
cimen, is a single slit, placed lengthwise, and not transverse to the 
head as in most Dol])hins, and tlie dorsal fin is merely a low ridge. 
The skull has a very remarkable form, having on the upper surface 
a pair of large, compressed, bony crests, which overarch the aper- 
ture of the nostrils and base of the rostrum, and nearly meet in 
the middle line above. The upper and lower jaws arc exceedingly 
long and narrow, and armed with numerous slender, pointed teeth, 
which undergo some curious changes of form as life advances. 
