were mistaken by that observer for teeth. It is curious that the name is really appropriate in spite of this mistake, though of course it would be so to all the Ziphioids. In more than one feature this genus comes nearest of all the Ziphiinae to Physeter. Its enormous maxillary crests are paralleled in that Whale; but in Hyperoodon their great thickness contrasts with the thinness of those of the Cachalot. The correspondence in the attachment of a rib to its vertebra by both heads is noteworthy. It is remarkable that in this particular Hyperoodon is more like Physeter than the supposed nearest ally of the latter—Kogia.
Of this genus two species are known. The best known is the common northern H. rostratum (with many aliases); the second species from the southern hemisphere, H. planifrons, is only known from a single water- and pebble-worn skull. Its identification, however, depends upon the known accuracy of the late Sir William Flower.
The northern species (Hyperoodon rostratum) has often been recorded upon our own coasts; the first record of the stranding of this Whale was in the year 1717. In that year an example was found at Maldon, in Essex. Like the Beluga, Hyperoodon rostratum gets lighter in colour with advancing years. The young are black; the old animals pale brown with some white about them. The under surface, however, is always greyish white. The length of this Whale reaches to at any rate 30 feet. But John Hunter had a specimen which he believed to be 40 feet in length. The specimen, however, consisted only of a skull, so that error might have crept in. It has already been mentioned that the old males have enormous maxillary crests. According to M. Bouvier, who has lately made an exhaustive examination of the anatomy of this Whale,[1] the females occasionally exhibit the same crests, which are thus presumably of the nature of spurs sometimes seen in old females among the Gallinaceous birds. The number of grooves upon the throat is in dispute in this Whale as in Ziphius. One pair is the usual allowance; but Kükenthal found four in some embryos studied by him. Attention has already been called to the voice of Ziphioid Whales. Hyperoodon neither "lows" nor "bellows," but "sobs"! Hyperoodon rostratum is a gregarious Whale, going about in herds, or "gams" as they should technically be termed, of four to ten or even fifteen. This Whale
- ↑ Ann. Sci. Nat. (7), xiii. 1892, p. 259.
