The genus Cystophora is the only other genus of which there is a British representative. It is called the Hooded Seal on account of an inflatable sac upon the face, with which it is said to attempt to terrify its enemies. The genus has an incisor less in each half of each jaw than Phoca and Halichoerus. Its formula is I 2/1 while these genera are both 3/2. C. cristata is a large species reaching a length of 10 feet. The colour of the back is dark grey with deeper coloured spots. A few individuals only have been recorded from our coasts.
Stenorhynchus ( = Ogmorhinus) is an Antarctic genus. The hind-feet are clawless. The incisors are 2/2. The molars have an additional cusp, i.e. three in all.
The genus Leptonyx with but one species, L. weddelli, is purely Antarctic in range. Like the last genus it has two incisors, and has but rudimentary claws upon the hind-feet; the first and fifth toes moreover are the longest. The genus chiefly differs from the last in the simple conical crowns of the molars, which have not the additional cusps of Stenorhynchus.
Ommatophoca is another Antarctic genus with but a single species, O. rossi. In this genus the hind-feet have no claws, and the first and fifth toes are longer than the others. The claws of the fore-feet are rudimentary. The immense size of the orbits gives the name to the genus. There are two incisors, and the molars are all very small.
Monachus is a northern genus inhabiting the Mediterranean and the Atlantic in the vicinity of Madeira and the Canary Islands. It has rudimentary nails upon both pairs of feet. The first and fifth toe of the hind-feet are longer than the others. As with the preceding genera, the incisors are two in each jaw. The species are M. albiventer, the Monk-Seal, and M. tropicalis, the Jamaica Seal.
Allied to Cystophora is the genus Macrorhinus, with (possibly) two species, of which one is Antarctic, the other frequents or frequented the coast of California. The incisors are two in the upper jaw, and but one in the lower. The premolars are four and the molar one; all the teeth are small and simple, but
have long roots. The nose of the male has a dilatable proboscis. The southern Elephant Seal is M. leoninus, and reaches a length of some 20 feet. It occurs on the shores of Kerguelen and some other more or less remote islands. Its habits have been studied and described by several observers, beginning with Anson in the last century. The late Professor Moseley gave a good account of this marine monster in his book on the voyage of the "Challenger." When the animal is enraged, the end of the snout is dilated; but when this happens there is no long and hanging proboscis such as has sometimes been described. The inflation affects the skin on the top of the snout, which thus rises rather upwards during inflation. The inflated region, according to Mr. Vallentin, quoted by Mr. J. T. Cunningham, is about 1 foot long in an individual of 17 feet. It has been stated that this proboscis is a temporary structure, only appearing in the breeding season; but recent observations have shown that this statement is inaccurate; it persists all the year round. The males fight greatly during the breeding season, and produce a roar which has been compared to the "noise made by a man when gargling." The females and the young males bellow like a bull. The males fight of course with their teeth, literally falling upon one another with their whole weight. Mr. Cunningham thinks that the use of the proboscis is to protect the nose from injury; or that it may be merely the result of "emotional excitement." In any case the Bladder-nosed Seal, Cystophora, is undoubtedly protected from injury by the possession of a corresponding hood. The nose is the most vulnerable place, and the existence of this hood would stave off the effects of a blow in that region. Moseley, however, has said of Macrorhinus that it cannot be stunned by blows on the nose as other Seals can; but he attributes this, not to the dilated snout, but to the bony crest on the skull, and to the strength of the bones about the nose. This Seal crawls with difficulty on the land, and as the animals move "the vast body trembles like a great bag of jelly, owing to the mass of blubber by which the whole animal is invested, and which is as thick as it is in a whale."[[313]] When lying on the shore, these animals scrape sand and throw it over themselves, apparently to prevent themselves from being
incommoded by the direct rays of the sun, to the effects of which they are very susceptible. The Elephant Seal is mild and inoffensive, unless enraged, and, of course, during the breeding season.
Order VIII. CREODONTA.
This entirely extinct group of Mammalia may be thus characterised:—Small to large carnivorous mammals, with skull on the whole like that of the Carnivora and with trenchant teeth; digits with unguiculate phalanges; tail long; extremities usually with five, sometimes with four digits. In the carpus a centrale is present, and the scaphoid and lunar are separate. Interlocking of posterior dorsal and lumbar zygapophyses very perfect. Brain small but convoluted.