Page:Encyclopædia Britannica, Ninth Edition, v. 22.djvu/462

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438 S R I S R I animal, it is far surpassed by many of the tropical mem- bers of the group, and especially by those of the Malayan region, where nearly all the numerous species are bril- liantly marked, and many are ornamented with variously coloured longitudinal stripes along their bodies. One of the commonest and best known of the striped species is the little Indian Palm Squirrel (S. palmarum), which in large numbers runs about every Indian village. Another Oriental species (S. caniceps) presents almost the only known instance among mammals of the temporary assump- tion during the breeding season of a distinctly ornamental coat, corresponding to the breeding plumage of birds. For the greater part of the year the animal is of a uniform grey colour, but about December its back becomes a brilliant orange -yellow, which lasts until about March, when it is again replaced by grey. The squirrel shown in fig. 2 is a native of Burmah and Tenasserim, and is FIQ. 2. Burmese squirrel. closely allied to S. caniceps, but goes through no seasonal change of colour. The number of species in the genus Sciurus is about 75, of which 3 belong to the Palsearctic, 15 to the Ethiopian, about 40 to the Oriental, and 1 6 to the combined Nearctic and Neotropical regions. Genus Kheithrosciurus. A single veiy striking species of squirrel, confined to Borneo, and as yet only known from three or four examples, has been separated genetically under the above name. The general shape of its skull is very diiferent from that of other squirrels ; but its most peculiar characteristic is the presence of from seven to ten minute parallel vertical grooves running down the front face of its incisors, both above and below, no other squirrel having really grooved incisors at all, and no other member of the whole order of rodents incisor grooves resembling these. . Its premolars only number {, and its molars are simpler and less ridged than in the other genera. This squirrel (Rh. macrotis) is a magnificent animal, far larger than the English species, with an enormously long bushy tail, long tufted ears, and black and white bands down its sides. Genus Xerus. Fur coarse and spiny. Claws long and comparatively straight. Ear-conches minute or entirely absent. Skull with the post-orbital processes short and directed backwards, the bony palate prolonged considerably behind the tooth-row, and the external ridge on the front face of the anterior zygoma-root more developed, and con- tinued much further upwards, than in Sciurus. Premolars f ; molars as in Sciurus. This genus contains four well-marked species, known as Spiny Squirrels, all natives of Africa. They are terrestrial in their habits, living in burrows which they dig for themselves. X, getulus, a striped species of North Africa, has much the size and appearance of the Indian palm squirrel ; the others are all a little larger than the English squirrel. Genus Tamias. The members of this genus are characterized by the possession of internal cheek -pouches, and by their style of coloration, all being ornamented on the back with alternate bands of light and dark colour. Their skulls are slenderer and lighter than those of the true squirrels, from which they differ in several unimportant details. There is only one functional premolar, the small anterior one usually found in Sciurus being either absent altogether or quite small and functionless. There are four species, all found in North America, one extending also through Siberia into eastern Europe. They are known in America as " Chipmunks," and are among the commonest and best known of the indigenous rodents. The members of this group seem rather to lead into the genus Spermo- pJiilus (see MARMOT) of the sub-family Arctomyina, so that the division of the Sciuridaz into two sub-families, although very con- venient for classification and description, is rather of an artificial nature, there being no well-defined line of separation between them. Genera Pteromys and Sciuropterus. The Flying Squirrels, although they cannot fly in the true sense of the word, can yet float through the air for considerable distances by the aid of an extension of skin connecting their fore and hind limbs, and forming a sort of parachute. This parachute is merely a lateral extension of the ordinary skin of the body, which passes outwards between the limbs and terminates at the wrists and ankles. In addition to the lateral membrane there is a narrow and in- conspicuous one passing from the cheek along the front of the shoulder to the front of the wrist, and another at least in the larger species stretching across behind the body from ankle to ankle and involving the base of tho tail. The flying squirrels are divided into two genera, of which Pteromys contains the larger and Sciuropterus the smaller species. The two differ in certain details of dentition, and in the greater development in the former of the expanded membranes, especially of the " interfemoral " or posterior membrane, which is in the latter almost wholly absent. In Pteromys the tail is cylindrical and comparatively thin, while in Sciuropterus it is broad, flat, and laterally expanded, and evidently compensates for the absence of the interfemoral membrane by acting as a supplementary parachute. In appearance flying squirrels resemble the non-flying forms, although they are even more beau- tifully coloured than the latter. Their habits, food, &c., are also very similar to those of the true squirrels, except that they are more decidedly nocturnal, and are therefore less often seen by the ordinary observer. Their method of leaping from tree to tree and floating long distances on their extended parachutes is precisely similar to that of the flying phalangers of Australia, a graphic description of which is quoted in PHALANGER (vol. xviii. p. 729). Of each of the two genera there are about thirteen or fourteen species, all natives of the Oriental region, except that one of Sciuropterus is found in North America, and another in Siberia and eastern Europe, the latter, the Sciurus volans of Linnams's Systcma Nature, being the first flying squirrel that was known to European naturalists. (0. T. ) SRINAGAR. See KASHMIR, vol. xiv. p. 11. SRfRANGAM, or SERINGHAM, a town of India, in Trichinopoli district, Madras presidency, situated in 10 51' 50" N. lat. and 78 43' 55" E. long., 2 miles north of Trichinopoli city and almost in the centre of the island of Srirangam. The island is formed by the bifurcation of the river Kaveri (Cauvery) and by the channel of the Colerun. The town is celebrated for its great temple dedicated to Vishnu, composed of seven square enclosures, 350 feet distant from each other. Each enclosure has four gates with high towers, placed one in the centre of each side opposite to the four cardinal points. The outer wall of the temple is not less than 4 miles in circumference. From 1751 to 1755 the island and its pagodas were the object of frequent contests between the French and the British. Srirangam was constituted a municipality in 1871, and since then much has been done to improve the place. In 1881 the population was 19,773 (9330 males and 10,443 females). SRIRANGAPATAM. See SEEINGAPATAM.