TOOTHED WHALES. 35 



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 12i feet in length. 



Whether Sowexby's whale ranges into the seas of the Southern Hemisphere 

 U cot 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 Layar.ls whale (.1/. 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 strapdike 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 Challenger, 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 a Hording 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. 



