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Show 1870.] DR. J. E. GRAY ON NEW TORTOISES. 707 Testudo mauritanica, Demoussy, Descr. de la Confederation Argentine, ii. 38. Hab. Chili (Weisshaupt); N. Patagonia (D'Orbigny) ; Mendoza and the Pampas (Burmeister) ; Monte Video and Buenos Ayres (Demoussy). Beak keeled in front and strongly bidentate. Shell depressed, oblong; middle of the back rather flattened, dirty yellow; areola central; nuchal plate distinct; marginal plates shelving, with a very short keel; front and hinder marginal plates reflexed, making a serrated edge ; head with one pair of supranasals ; a hexangular (central) and two triangular frontal plates between the eyes, with some small shields between them and the supranasals, and a pair of elongated occipital plates ; fore legs with a large spur at the elbow-joint, and numerous conical spines on the underside of the thighs, two of which are larger than the rest. The scales in front of the fore legs very large, unequal, convex. This species is very like T. sulcata from Abyssinia in colour and general appearance ; but the shell is much more depressed, and the marginal shields, which in that species are very high, with a sharp, narrow keel beneath, are in this species only moderately high and very sharply keeled. The pectoral plates are narrow towards the centre, and gradually spread out in a triangular shape, one-third from the centre; while in T. sulcata these plates are narrow and linear for two-thirds of their width and then suddenly expand into a pentangular disk. In this species the last vertebral shield is the width of the caudal, and one-half of the last and one-half of the last but one of the hinder marginal shields, whereas in T. sulcata it is only the width of the caudal and one-half of the last hinder marginal shields. The reception of specimens of Testudo elephantopus and T. chilensis direct from South America, and the power of comparing them with specimens of Testudo indica from Seychelles and other localities in the Old World, and with Testudo sulcata from Africa, have been very important, as by the comparison of the actual specimens of these animals together it has been distinctly proved that, instead of the same species inhabiting the Old and the New World (which was an anomaly among the Testudinata), these species, which have been regarded as the same, are perfectly distinct; indeed Testudo sulcata from Africa is not only distinct from T. chilensis, but the two species belong to two different subgenera, the one belonging to the Old and the other to the New World. The only other instance, of which I am aware, of a land-Tortoise being supposed to be common to the two continents, is a species of Kinixys, which was first received from Demarara and Guadeloupe, but which is now known to be an African genus ; and the specimens must have been taken to Demarara by some ships from Africa; for I am informed that it is not even colonized*, much less naturalized, in that country ; but it is probable that some of the negroes who are fond of living animals may have taken them with them. |