carnassial with a trenchant tricuspid blade, and a very large inner lobe, hollowed on the free surface, with a raised sharp edge, and extending along two-thirds or more of the length of the blade. True

molar large, with a quadricuspidate crown, broader than long. First upper premolar very small, and in some cases absent (Fig. 261). Skull broad and depressed, contracted immediately behind the orbits. Facial portion very short; brain case large. Vertebræ C 7, D 14-15, L 6-5, S 3, C 20-26. Body very long. Ears short and rounded.

Limbs short. Feet more or less completely webbed; claws usually well developed on all the toes, although they may be rudimentary or absent. Tail long, thick at the base and tapering, rather depressed. Fur short and close. The humerus may or may not have an entepicondylar foramen. In conformity with the shape of the skull, the posterior part of the brain is expanded laterally. The Common British Otter (L. vulgaris), as the type of the genus, may be described somewhat fully. It has an elongated, low body, short limbs, short broad feet, with five toes on each, connected together by webs, and all with short, moderately strong, compressed, curved, pointed claws. Head rather small, broad, and flat; muzzle very broad; whiskers thick and strong; eyes small and black; ears short and rounded. Tail a little more than half the length of the body and head together, very broad and strong at the base, and gradually tapering to the end, somewhat flattened horizontally. The fur is of very fine quality, consisting of a short soft under fur of a whitish-gray colour, brown at the tips, interspersed with longer, stiffer, and thicker hairs, very shining, grayish at the base, bright rich brown at the points, especially on the upper parts and outer surface of the legs; the throat, cheeks, under parts and inner surface of the legs brownish-gray throughout. Individual Otters vary much in size; but the total length from the nose to the end of the tail averages about 3 feet, of which the tail occupies 1 foot 3 or 4 inches. The weight of a full-sized male is from 18 to 24 lbs., that of a female about 4 lbs. less.

As the Otter lives almost exclusively on fish, it is rarely met with far from water, and usually frequents the shores of brooks, rivers, lakes, and, in some localities, the sea itself. It is a most expert swimmer and diver, easily overtaking and seizing fish in the

water, but when it has captured its prey it brings it to shore to devour it. When lying upon the bank it holds the fish between its fore-paws, commences at the head, and then eats gradually towards the tail, which it is said always to leave. The female produces three to five young ones at a time, in the month of March or April, and brings them up in a nest formed of grass or other herbage, usually placed in a hollow place in the bank of a river, or under the shelter of the roots of some overhanging tree. The Common Otter is found in localities suitable to its habits throughout Great Britain and Ireland, though far less abundantly than formerly, for, being very destructive to fish, and thus coming into keen competition with those who pursue the occupation of fishing either for sport or for gain, it is rarely allowed to live in peace when once its haunts are discovered. Otter-hunting with packs of hounds of a special breed, and trained for the purpose, was formerly a common pastime in the country. When hunted down and brought to bay by the dogs, the Otter is finally despatched by long spears carried for the purpose by the huntsmen.

The Common Otter ranges throughout the greater part of Europe and Asia, the Indian L. nair not being distinct. A closely allied but larger species, L. canadensis, is extensively distributed throughout North America, where it is systematically pursued by professional trappers for the value of its fur. The Common Otter is regularly trained by the natives of some parts of Bengal to assist them in fishing, by driving the fish into the nets. In China Otters are taught to catch fish, being let into the water for the purpose attached to a long cord.

Otters are widely distributed over the earth, and, as they are much alike in size and coloration, their specific distinctions are by no means well defined.1 Besides those mentioned above, the following may be noticed. In the Oriental region there are L. ellioti of India, L. sumatrana of the Malay countries, and L. cinerea ranging over the greater part of the region. The latter species (often known as L. leptonyx) is of small size, with a short head, and rudimentary claws, which may be absent; it was at one time. regarded as generically distinct, under the name of Aonyx. The upper true molar (Fig. 261) is characterised by the great development of its inner tubercular portion, and the first upper premolar is absent. In the Ethiopian region there are two species, L. capensis and L. maculicollis. Of the Neotropical forms it will suffice to mention the small L. felina and the large L. brasiliensis. The latter is by far the largest of the existing forms, and is characterised by the presence of a prominent flange-like ridge along each lateral 1 See Thomas, Proc. Zool. Soc. 1889, p. 190.

2 The synonomy of this species is not settled, and the adoption of the name given here only preliminary.

margin of the tail, on which account it was referred by Dr. Gray to a distinct genus, with the name of Pteronura sambachi. It should be observed that all Otters have a very distinct inner cusp to the blade of the lower carnassial, but that the relative size of this cusp varies in the different species.

Extinct Otters.-Several species of fossil Otters have been described. Thus in the Indian Siwaliks we have L. palaindica, which is closely allied to L. sumatrana, and a larger form described as L. bathygnathus. The Pliocene of Hessen-Darmstadt yields L. hessica; while L. dubia, of the Middle Miocene of France, is a species characterised by the small size of the inner cusp of the lower carnassial-a character in which it resembles those Tertiary forms described as Trochictis, which are believed to connect Lutra with the Musteline. Two very large Otters, respectively from the Indian Siwaliks and the Italian Miocene, named L. siralensis and L. campanii, may be regarded either as representing a very distinct Enhydriodont group of Lutra or as referable to a separate genus Enhydriodon. They are characterised by certain peculiarities in the structure of the teeth, and the second upper premolar may be absent in the Indian form. Lastly, the genus Potamotherium contains a small Otter (P. valetoni) from the Lower Miocene of the Continent, which differs from all other known Mustelide in having a minute second upper true molar. This species is evidently a very generalised form approximating to the Viverride in its dental formula, and also in the characters of the teeth themselves. The brain, as recently described by Dr. Filhol, differs from that of Lutra and other Mustelines in the great relative width of the anterior extremity of the hemispheres and olfactory lobes, and also in the disposition of the sulci, in both of which respects it more nearly resembles the Viverrida.

Latax.1-Dentition: i, c, p, m; total 32. Differs from all other existing Carnivora in having but two incisors on each side of the lower jaw, the one corresponding to the first (very small in the true Otters) being constantly absent. Though the molar teeth generally resemble those of Lutra in their proportions, they differ very much in the exceeding roundness and massiveness of their crowns and bluntness of their cusps. Feet webbed. Fore feet small, with five subequal toes, furnished with short compressed claws; palms naked. Hind feet very large, depressed, and finlike. The phalanges flattened as in the Seals. The fifth toe the longest and stoutest, the rest gradually diminishing in size to the first, all with moderate claws. Tail moderate, cylindrical, and obtuse; about one-fourth the length of the head and body.

1 Gloger, Nova Acta Ac. Cos. Leop.-Car. vol. xiii. pt. 2, p. 511 (1827): Syn. Enhydra; Fleming, Philosophy of Zoology, vol. ii. p. 187 (1822). Preoccupied by Enhydris, Merrem, Tent. Syst. Amphib. p. 140 (1820).

The Sea-Otter (L. lutris, Fig. 262) is the sole representative of this genus. The entire length of the animal from nose to end of tail is about 4 feet, so that the body is considerably larger and more massive than that of the English Otter. The skin is peculiarly loose, and stretches when removed from the animal so as to give the idea of a still larger creature than it really is. The pellage is remarkable for the preponderance of the beautifully soft woolly under fur, the longer stiffer hairs being very scanty. The general colour is a deep liver brown, everywhere silvered or frosted with the hoary tips of the longer hairs. These are, however, removed when the skin is dressed for commercial purposes.

FIG. 262.-The Sea-Otter (Latax lutris). From Wolf, Proc. Zool. Soc. 1865, pl. vii.

Sea-Otters are only found upon the rocky shores of certain parts of the North Pacific Ocean, especially the Aleutian Islands and Alaska, extending as far south on the American coast as Oregon; but, owing to the unremitting persecution to which they are subjected for the sake of their skins, which rank among the most valuable known to the furrier, their numbers are greatly diminishing, and, unless some restriction can be placed upon their destruction, such as that which protects the Fur-Seals of the Pribyloff Islands, the species is threatened with extermination, or, at all events, excessive scarcity. When this occurs, the occupation of five thousand of the half-civilised natives of Alaska, who are dependent upon Sea-Otter hunting as a means for obtaining their living, will be gone. The principal hunting grounds at present are the little rocky islets and reefs around the island of Saanach and

the Chernobours, where they are captured by spearing, clubbing, or nets, and recently by the more destructive rifle bullet. They do not feed on fish, like the true Otters, but on clams, mussels, seaurchins, and crabs, for the mastication of which the blunt cusps of their teeth are admirably suited. The female brings forth but a single young one at a time, apparently at any season of the year. They are excessively shy and wary, and all attempts to rear the young ones in captivity have hitherto failed.

Subfamily Melinæ.-Feet elongated. Toes straight. Claws non-retractile, slightly curved, subcompressed, blunt; those of the fore foot especially large. Upper molar variable. Kidneys simple. Habits mostly terrestrial and fossorial.

Mephitis.-Dentition: i, c, p, m; total 34. Upper molar larger than the carnassial, subquadrate, rather broader than long. Lower carnassial with talon less than half the length of the whole tooth. Bony palate terminating posteriorly opposite the hinder border of the last molar tooth. Facial portion of skull short and somewhat truncated in front. Vertebræ C 7, D 16, L 6, S 2, C 21. Head small. Body elongated. Limbs moderate, subplantigrade. Ears short and rounded. Tail long, abundantly clothed with very long fine hair. Anal glands largely developed. The secretion of these glands, which can be discharged at the will of the animal, has an intolerably offensive odour, which circumstance has rendered the Skunks, as they are commonly called, proverbial. They are strictly nocturnal animals, terrestrial and burrowing, feeding chiefly on small mammals, birds, reptiles, insects, worms, roots, and berries. All the known species have a prevalent black colour, varied by white strips or spots on the upper part (Fig. 263). They generally carry the body much arched, and the tail erect, the long loose hair of which waves like a plume over the back. There are three species, all inhabitants of the American continent, over which they have an extensive range.

The Common Skunk (M. mephitica, Fig. 263) is an animal of about the size of a small Cat, ranging from Hudson's Bay to Guatemala. The following account of its habits is given by Dr. C. H. Merriam in his Mammals of the Adirondack Region:

"The skunk preys upon mice, salamanders, frogs, and the eggs of birds that nest on or within reach from the ground. At times he eats carrion, and if he chances to stumble upon a hen's nest the eggs are liable to suffer; and once in a while he acquires the evil habit of robbing the hen-roost, but as a rule skunks are not addicted to this vice. Of all our native mammals perhaps no one is so universally abused and has so many unpleasant things said about it as the innocent subject of the present biography; and yet no other species is so valuable to the farmer. Pre-eminently an insect-eater, 1 Cuvier, "Tabl. de Classif." in Leçons d'Anat. Compar, vol. i. (1800).