262 MAMMALIA OF INDIA. 
Dentition: 1—1 = 20, 
S1zE.—Six to seven feet. 
The peculiarity of this cetacean is the preponderance of the cranial 
over the rostral part, more so, as Professor Owen remarks, than in any 
other species. ‘The asymmetry of the bones too is remarkable, although 
this is characteristic of all the catodon whales, especially as regards the 
bones of the anterior narial passages, the left of which is very much 
larger than the right. This is also the case in the large sperm whale, 
but in Zuphysetes the disproportion is still greater. In a notice on a 
New Zealand species (Z. Pottsiz), by Dr. Julius Haast, he gives the 
difference as fifteen times the size of the right aperture; the mouth is 
also peculiar from its position and small size, being very much over- 
shot by the snout. It may, as Dr. Haast supposes, be a ground feeder, 
existing on the smaller hydroid zoophytes, otherwise it must, I think, 
turn on its side in seizing its prey. 
MYSTICETE—WHALEBONE OR BALEEN WHALES. 
GENUS BALA NA—THE RIGHT WHALES. 
They are distinguished from the last group by their enormous heads, 
with more symmetrical skulls, the facial portion of which is greatly in 
excess of the cranial. The bones of the lower jaw are not united at the 
symphysis, but are held together by strong fibrous bands; the two rami 
are very much rounded and arched outwards; there are no teeth. The 
maxillary and premaxillary bones are much produced, forming a 
rostrum tapering, narrow, compressed and much arched in the night 
whales. From this depends the mass of whalebone, which grows from 
a fleshy substance “similar,” as is aptly described by Dr. Murie, “ to 
the roots of our finger-nails. It grows continuously from the roots like 
the latter, and in many respects corresponds, save that the free end is 
always fringed. Baleen, therefore, though varying from a few inches to 
a number of feet long, in fact approximates to a series of, so to say, 
mouth nail-plates, which laminz have a somewhat transverse position 
to the cavity of the mouth, and thus their inner split edges and lower 
free ends cause the mouth to appear as a great hairy archway, shallower 
in front and deeper behind” (Cassell’s Natural History). 
The object of this vast amount of whalebone is to strain from the 
huge gulps of water the mollusca, &c., on which this animal feeds. 
The tongue of these whales is very large, filling up the space. between 
the lower jaws.. The gullet is small in comparison. The nasal aperture 
differs from the Devticefe in being symmetrical, that is, having the 
