The genus _Neobalaena_ is interesting from more than one point of view. Its size compared with its gigantic relatives is small, some 16 or 17 feet. The genus bears the same kind of proportion to _Balaena_ that _Kogia_ does to _Physeter_ among the Physeteridae. It is one of those Whales which are very restricted in habitat; up to the present it is only known from the Antarctic region in the neighbourhood of New Zealand and South Australia. Structurally it is in a few points intermediate between the Right Whales and the Rorquals. The head is proportionately (as well as, of course, actually) not so large as in _Balaena_. There is a falcate dorsal fin; but the head in outline is not Rorqual-like in spite of its similar proportions. The whalebone is long. The throat is not grooved. _Neobalaena_ has forty-three vertebrae, of which the cervicals are all fused. There are as many as seventeen or eighteen dorsal vertebrae, the largest number in any Cetacean as far as is known. With these are articulated not eighteen but only seventeen ribs. The first dorsal vertebra appears to be without a rib. The ribs are very broad and flat. The body thus gets an appearance of a Sirenian. The lumbar vertebrae are fewer than in any other Cetacean, being only two. The scapula is more like that of the Rorquals than that of the Right Whales; {362} 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_.[245] SUB-ORDER 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:--All 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 symphysis of the mandible is long. Teeth, more or fewer, are found in both jaws, but those of the mandible are alone functional (? exc. _Kogia_). The pectoral limb is smallish. The throat is grooved by two or four furrows.