Page:The American Cyclopædia (1879) Volume XV.djvu/842

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812 TORTOISE east of the Alleghanies; it often comes on land, to feed on worms and orthopterous in- sects ; it is about 5 in. long, 3 in. wide, and If in. high. The geographic tortoise (graptemys geographic^ Ag.) is so called from the network of reddish brown lines spread irregularly over the dark brown carapace, somewhat resem- bling the outlines of countries on a map. It is one of the most active and bold of the family, Shell of Speckled Tortoise (Nanemys guttata). and is found from New York and Pennsylvania to Michigan, Tennessee, and Arkansas ; it is over 8 in. long, 6 in wide, and 3 in. high, with a tail of 2^ in. The sculptured tortoise (glyptemys insculpta, Ag.) is very common in the northern states as far south as New Jer- sey ; the carapace is reddish brown, each scale with radiating yellow ridges, often smoothed down in old specimens; marginal plates and sternum yellow, each with a black spot at the posterior angle, and generally with concentric striaB ; limbs brick-dust color below ; it is 8 in. long, 5 in. broad, and about 3 in. high, with a tail of over 2 in. ; it passes long periods away from water. Blanding's tortoise (emys melea- gris, Ag.) is the only true species of the genus here ; it is black above with numerous yellow spots, sometimes arranged in lines ; below dusky yellow, each plate with a large quad- rangular dark spot at the outer and posterior angle. It is found from New England west- ward to Wisconsin, being most abundant on Sculptured Tortoise (Glyptemys insculpta). the prairies, and very terrestrial in its habits; it is 8 in. long, 5 in. wide, and 3 in. high, with a tail of 2| in. The box or checkered tortoise (cistudo Virginea, Ag. ; C. clausa and Carolina of other authors) has a rough and strong shell, generally of a light brown- ish color with very numerous bright yellow blotches and lines, more or less radiating, giving somewhat the appearance of tortoise shell; sternum usually yellowish with dark blotches ; hind feet plantigrade ; plastron with a hinge in the middle, so that the anterior and posterior portion can each be brought in contact with the carapace, and enclose the animal in a per- fect box. It is about 6 in. long, 4 in. wide, and 2 in. high ; it is found from New . England south to the 8hdl of *$$> (Cl8tud * Carolinas, and west to Michigan; it is entirely terrestrial, and a very poor swimmer ; it is common in the pine barrens of the southern states, where it is called cooter and pine terrapin by the negroes ; it feeds on insects and succulent plants, and is easily domesticated. In the testudinina or land tortoises the carapace is entirely ossified, very convex in the middle region, but well balanced ; the plastron is broad, flat, and solid ; openings for protrusion of limbs small and narrow; head, limbs, and tail completely re- tractile within the shell, and the plastron in some with movable lobes; head small and shielded, nose broad, and eyes far apart ; alve- olar margin with a sharp edge, and the jaws fitting closely by ridges and furrows; skin everywhere more or less scaly ; toes mostly concealed under the skin, as far as the last joints, which are free and covered by flat sharp nails, usually five anterior and four posterior ; feet short, stout, and somewhat clubbed ; the great intestine is longer and the lungs are larger than in any other testudinate, in relation with the greater convexity of the shell. They are most abundant in warm climates, and are the largest of the order, the great Galapagos tor- toise being 3 to 4ft. long, the African coui (psammobates radiatus, Fitz.) 1 ft., the gopher 1 ft., and the common European land tor- toise 8 in. (the smallest of the family). Here also belongs the fossil gigantic colossochelys Atlas (Cautl. and Falc.), from the Sivalik hills, which must have measured nearly 18 ft.' in length ; it is found with the great extinct un- gulates which it so much resembled in gait and habits. There are no tortoises indigenous to the British islands, though they might easily be naturalized there. Agassiz places all the American testudinina in the genus xerobates. They live entirely on land, and when put into water walk on the bottom ; the body is raised on the last joint of the toes, and the gait is firmer, more steady, and less slow than in any other tortoise. Their food consists of succu- lent plants and fleshy fruits. There are only eight genera, but many species. The gopher tortoise (testudo polyphemus, Daudin) is about 15 in. long, and has a nearly flat shell, the plates marked with concentric strife disappear- ing in old age; the plastron is thick and firm, projecting beyond the carapace in front, and deeply emarginate behind ; the head is short,