TORTOISE, tOetus (OF. tortue, tortug-ue, Fr. tortue, tortoise, from Lat. tortes, twisted, so called on account of its crooked feet; prob ably influenced its termination by Eng. por poise). A turtle of terrestrial habits. The term is rather indefinite, but usually dis tinguishes land chelonians from marine spe cies, although tortoise-shell is exclusively a marine product, and certain fresh-water turtles, as the terrapins, are commonly spoken of as marsh-tortoises. Its most exact applica tion is probably to the family Testudinithe, in which the shell is always covered with well developed horny shields. It includes the rapins or aquatic 'mud turtles' of the genera Emys, Chrysemys, and similar groups, in which the feet are adapted for both walking and swim ming, and the carapace is often ornamented by gay colors or sculpturings. Many are almost wholly terrestrial, as is the case with the com mon box-tortoise (see TURTLE) of the United States. Near allies are the famous Greek tor toise of the Mediterranean region and many other species of the typical genus Testudo; also the Florida 'gopher' (q.v.).
The most important and distinctive members of the group are the gigantic land-tortoises of various oceanic islands, now extinct or nearly so. (See EXTINCT ANIMALS.) All these belong to the genus Testudo and differ little except in size from the other members of the family. some of them are not larger than other large turtles, but those most noted greatly exceed any other living forms, although surpassed by the Testudo atlas of the early Pliocene in India, whose shell was six feet or more in length. Others, with shells about four feet in length, were its contemporaries in Europe and in North America. Their representatives survived until a recent date or still live in the Galfipagos Isl ands, Madagascar, and the Mascarene Islands, but nowhere upon any continent.
Specimens of small species have been known to live more than 100 years, and one, at least, more than 150 yedrs. The Madagascar species (Testudo Grandidieri) became extinct probably before that island was discovered by white men, but at least two species of the Camoros have re mained until within historic times. One (the elephant tortoise, Testudo giguntea, see LAND TORTOISE) is now extinct in its original home, the North Island of Aldabara, but preserved in the Seychelles, and a specimen living in England in 1897 then measured X 50 inches over the curve of its shell, and weighed 358 pounds; an other in Saint Helena was more than a century old in 1900. Daudin's tortoise, of South Alda
bars, also survives in small numbers, and several were taken to Europe in 1895, one of which at least 100 years old had a shell 55 inches long. Still larger is a representative alive in Mauri tius, whose recorded history goes back to 1766, when it had already reached large size; it is of n species (Sumeirei) native to the Seychelles, to which also belonged the tortoise which lived at Colombo from 1797 to 1898. Several other species, probably or surely extinct, inhabited Rodriguez and other islands of the Indian Ocean, where they were found in abundance by the early voyagers and planters, but were slaughtered for food or as curiosities.
The Gahipagos Islands had several species of similar gigantic tortoises, one to each island of the archipelago, which differed from the Eastern ones mainly in having longer necks and smaller heads. Some were long ago exterminated by man or by the pigs which Ecuadorans turned loose upon the islands a century ago; others still survive in small numbers, although in 1893 and again in 1898 large numbers were taken away and dis tributed to zoological gardens in various parts of the world, New York and Washington getting several old and young specimens. The largest collection of all living species is that at Tring Park, England, where the biggest known Gala pagos tortoise (Testudo elephantopus) is one measuring 56 X 49 inches over the curve of its carapace, which was taken from Duncan Island in 1813 to Rotuma, thence to Sydney in 1880, and finally to England.
Consult: Gunther, Gigantic Land-Tortoises (London, 1877) ; (Mather, Proceedings Linnean Society (Presidential address, 1898—"a fascinat ing review of the whole complicated subject") ; Gadow, Amphibia and Reptiles (London, 1901) ; Darwin, A Naturalist's Voyage (London, 1860) ; Report United States National Museum (Wash ington, 18S9). Compare TURTLE; and see illus tration under LAND TORTOISE.