TOOTHED WHALES. 
35 
Layard’s Whale. 
under-parts was a light slate. The body was also marked with a number of whitish 
spots, which were most numerous on the sides; these spots being in some places 
connected by narrow streaks. Other individuals are described as being nearly 
black above, while in others the tint becomes more decidedly blue. A specimen 
captured at New Jersey in 1889 measured 12§ feet in length. 
Whether Sowerby’s whale ranges into the seas of the Southern Hemisphere 
is not definitely ascertained, although, as already mentioned, the genus is more 
abundantly represented there than to the north of the equator; and it is still a 
question whether many of the southern forms, to which separate names have been 
received, are entitled to rank as distinct species, or whether they should be 
regarded as merely varieties of the European one. 
Layard’s whale {M. layardi), from the Cape of Good Hope and 
the seas of the other parts of the Southern Hemisphere, is, however 
undoubtedly a very well-marked species, characterised by the enormous develop¬ 
ment of the strap-like teeth, to which allusion has already been made. The late 
Prof. Moseley, in describing a skull of this species obtained at the Cape during the 
voyage of the Chcdlenger, observes that “ these two teeth in the adult animal 
become lengthened by continuous growth of the fangs into long curved tusks. 
These arch over the upper jaw or beak, and crossing one another above it at their 
tips, form a ring round it, and lock the lower jaw, so that the animal can only open 
its mouth for a very short distance indeed. The tusks are seen always to be worn 
away in front by the grating of the confined upper jaw against them. How the 
animal manages to feed itself under these conditions is a mystery. It is remarkable 
that the main mass of each tusk is made up of what appears to be an abnormal 
growth of the fang. The actual conical tooth, that is the original small cap of 
dentine [ivory] of the tooth of the young animal, which corresponds to the part of 
the teeth showing above the gum in other whales, does not increase at all in size, 
but is carried up by the growth of the fangs, and remains at the tips of the tusks 
as a sort of wart-like rudimentary excrescence.” That these enormous teeth can 
be of no possible advantage to their owner appears perfectly clear; and they must 
probably be regarded as affording an instance of semi-monstrous development 
analogous to the one displayed by the tusks of the babirusa. 
A specimen stranded at the Cape was said to be black above and white 
beneath, with the division between the two tints sharply defined. One measuring 
something over 16 feet in length yielded eighty gallons of oil of a superior 
quality. The species appears excessively rare; and the known examples have 
been stranded. 
The last representative of this group is Arnux’s whale (Berardius 
' arnuxi), from the New Zealand seas, which attains a length of about 
30 feet. It differs from all the other forms in having two pairs of teeth near 
the front of the jaw; the first pair being placed close to the tip of the jaw 
and larger than the second pair. They are of moderate size, flattened from 
side to side, pointed at the tips, and inclined directly forwards. The skull lacks 
the high crests above the opening of the nostrils characteristic of the three 
preceding genera; and the long and narrow beak is less solidly ossified than in 
the beaked whales. 
