3262 TOOTHED WHALES CHAP. 
that is to say, it is long and not very high. The skull is most 
like that of Balaena, but the process of the frontal arching over 
the eye is broader relatively than in Balaena, and thus approaches 
Balaenoptera. Nothing is known of the viscera of this Whale. 
The whalebone is white, and the animal was first described by 
Dr. Gray from pieces of “bone.” It is not always that so 
fortunate a diagnosis of specific or generic difference has been 
made from a structure which apparently offers so little aid for 
discrimination. 
There is but a single species of the genus which is named 
Neobalaena marginata.' 
Sus-OrpDER 2. ODONTOCETI. 
The Odontoceti have teeth but no whalebone; the blow-hole 
is single; the skull is not symmetrical; some of the ribs are 
two-headed. 
Fam. 1. Physeteridae.—This family of the Odontocetes may 
be thus defined :—AIl or most of the cervical vertebrae are fused 
together. The costal cartilages are not ossified. In the skull the 
pterygoids are thick and meet in the middle line; the sym- 
physis of the mandible is long. Teeth, more or fewer, are found 
in both jaws, but those of the mandible are alone functional 
(?exe. Kogia). The pectoral limb is smallish.- The throat is 
grooved by two or four furrows. 
This family of Whales is again susceptible of division into 
the two sub-families—Physeterinae or Sperm Whales and the 
Ziphiinae. or Beaked Whales. Professor P. J. yan Beneden was 
strongly against any subdivision of what is here regarded as a 
perfectly natural family, embracing the Physeters and the Beaked 
Whales. There are, however, some reasons for the subdivision. The 
Ziphiinae have a reduced series of teeth, never exceeding two on 
each mandible, which contrasts with the fully-toothed mandibles 
of both Physeter and Kogia. The stomach of the Ziphioids is 
extraordinarily complicated even for a Cetacean. The small 
head of the latter group, which recalls in a curious way that of 
Mosasauroid reptiles and some Dinosaurs, is in contrast to the 
1 For osteology see Hector, Trans. New Zeal. Inst. vii. 1876, p. 251; and 
3eddard, Trans. Zool. Soc. xv. 1901, p. 87. 
