XII VOICE OF MESOPLODON 369 
Ziphioid grooves upon the throat. Nothing is known of the 
structure of the internal viscera of this Whale. It appears not 
to be really limited to the region of New Zealand, as is often 
stated, for Malm has lately described a skull (Berardius vegae) 
from Bering’s Straits.! 
Mesoplodon® is a world-wide genus embracing a number of 
species ; on the lowest estimate seven species can be distinguished, 
and Sir W. Flower would add two more. These are moderate- 
sized Whales, 15 to 17 feet in length. In the skull the mesethmoid 
is ossified; the nasals are sunk between the upper ends of the 
premaxillae. There are but a single pair of teeth in the mandible 
attached to nearly the middle of its length (whence the generic 
name). The vertebral formula is C 7, D 9 or 10, L 10 or 11, 
Ca 19 or 20. The sternum consists of four or five pieces. The 
amount to which the cervical vertebrae are fused varies; but 
some are always fused. 
The only species which has ever been stranded on the shores 
of this country is Jf bidens, an example of which was described 
many years ago as the “ Toothless Whale of Havre”; it was an 
old animal which had probably lost its teeth. Nevertheless it 
received the separate generic and specific name of Aodon dalei. 
The animal lived for two days out of the water, and made a sound 
like the “lowing of a cow.” An instance of the rarity of the 
Whales of this genus is afforded by JZ ewropaeus, of which only a 
single skull is known; this was extracted from a dead body, found 
floating, about the year 1840. It has never appeared since. 
M. layardi is remarkable on account of the very large size of its 
strap-shaped teeth; these curve over the upper jaw in such a 
way as to prevent the animal from fully opening its jaws. The 
case is curiously paralleled by the Sabre-toothed Tiger. This 
species is antarctic in range. From the opposite extremity of the 
globe comes M. stejnegeri, again known by but a single skull. It 
is singular on account of the large size of the brain case, and is a 
native of Bering’s Straits. JZ. hectori has its two teeth situated 
quite at the extremity of the mandible, and in this feature 
approximates to the genus Berardius. It was, indeed, confounded 
with that genus by one naturalist. 
! Bihang Svensk. Akad. Hand. viii. 1883. 
2 Flower, Zrans. Zool. Soc. x. 1878, p. 415; and H. O. Forbes, Proc. Zool. Soc. 
1893, p. 216. 
Olax 2B 
