There are also a number of osteological characters in which the two Physeterines differ from each other. In Kogia all the cervical vertebrae are ankylosed together; the skull is short, though equally asymmetrical; the ribs are as many as twelve or

fourteen; the scapula has not the concave face that it has in Physeter. The functional teeth of the lower jaw seem to be reinforced by two on each side of the upper jaw. Moreover, the articulation of the ribs with the vertebrae does not show the very anomalous state of affairs that characterises Physeter, where the two heads of a rib may be upon one vertebra.

While there is no doubt as to the generic distinctness of Kogia, there is again the same difficulty that is met with throughout the whole of the order in settling into how many species the genus requires dividing.

We can dismiss, as unnecessary, additional generic names (Euphysetes, Callignathus), but there do appear to be reasons for allowing two species, if the accounts of their osteology are to be depended upon. One of these is K. breviceps, with thirteen pairs of ribs, no teeth in the upper jaw, fourteen or fifteen on each side of the lower jaw, vertebral formula C 7, D 13, L 9, Ca 25, and phalangeal formula I 2, II 8, III 8, IV 8, V 7.

The other will then be K. simus, with fourteen pairs of ribs, two teeth in the upper jaw, nine in each ramus of the lower jaw, vertebral formula C 7, D 14, L 5, Ca 24, and phalangeal formula I 2, II 5, III 4, IV 4, V 2.

A Californian species has been called K. floweri, whose teeth seem to be particularly long and recurved. And the New Zealand K. pottsi has been held to be also a distinct form. There seems to be nothing of special interest to record about the way of life of these Cetaceans, which are but imperfectly known.

Sub-Fam. 2. Ziphiinae.—Teeth in the lower jaw not more than two on each side. A distinct lachrymal bone. Stomach with very numerous compartments.

These Whales are all of moderate size, not exceeding 30 feet or so in length. They have a falcate dorsal fin rather near the end of the body; the muzzle is prolonged, hence the name often given to them of "Beaked Whales." The throat is grooved; the blow-hole is single and median, crescentic in form, with the concavity pointing forwards. A character possibly differentiating the Ziphioids from other Whales is the fact that the body ends in a rounded projection between the flukes of the tail. This has at any rate been noted in Mesoplodon, Ziphius, and Hyperoodon. The Ziphioid Whales are by no means common; indeed of Berardius but four or five specimens have ever been

met with. Most of them are southern in range, and the vast stretches of desolate coast which occur in these regions of the world account possibly for the rarity of their remains. These Whales have done duty more than once for the "Sea Serpent." Quite recently an alleged sea serpent turned out to be a couple of Mesoplodon lying head to tail! The head in these Whales is small compared to the body. The skull is characterised by the strong maxillary crests, enormously developed in the male Hyperoodon. The vertex of the skull too is raised, forming a pronounced prominence behind the aperture of the nares (blow-hole); in many forms the rostrum is made of very dense bone, and is thus relatively abundant in rock strata. The pterygoids meet in the middle line as in the Cachalot. In addition to the few functional teeth in the lower jaw there are more numerous but small teeth in the upper jaw. These are not always to be recognised, as they are not attached to the bone, but merely imbedded in the gums, so that they come away when the skull is prepared.

The genus Berardius[[240]] differs from Mesoplodon by its rather more symmetrical skull, of which the vertex is formed by the nasals. The mesethmoid is only partly ossified. The teeth are two on each side of the mandible, with their apices directed forwards. The vertebral formula is C 7, D 10, L 12, Ca 19.