284 THE GALAPAGOS TORTOISES. 



determine the habitat. There is nothing in its structure that would preclude 

 an eventual determination of an origin, either indirect or direct, among the 

 Galapagos. It has close affinities to their species though in some respects its 

 peculiarities do not permit identification with any of which descriptions or 

 figures have been published. Its outlines are suggestive of the wider and shorter 

 individuals of T. elephantina Dumeril et Bibron. It has two gulars but no 

 nuchal plate. 



Direct Direct Curved Curved Circum- 



length width length width Height ference 



25f in. 20 in. 30| in. 32f in. 12| in. 51| in. 



Height to nuchal notch 10, to middle of back 12j, and to lower edge of caudal 

 scale 1| inches. The bones are thin and light, the entire weight, with attached 

 scales, being less than five pounds. All sutures are complete and firmly joined 

 excepting those at the inner edge of the marginals from the first vertebral to 

 the edges of the supracaudal. The bones of the back at the lower edges of the 

 costals are separated from those under the marginals by a space and their only 

 connections are made by the ribs, except at the nuchals and at the supracaudals 

 where they are rigidly united by broad anchyloses. The conditions along 

 the flanks are like those existing on the very young of other species. The scutes 

 are thin and fragile, the areolar spaces are small; the concentric striae are 

 numerous, narrow, and sharp. The carapace is short and broad and is broadly 

 arched on the back. In front from the middle of the second vertebral, through 

 the first, the descent is about as in T. vicina Giinther. Fourth vertebral nar- 

 row behind, hind edge about 3f times in front edge. Seen from above the 

 shape approaches the subquadrangular, owing to a considerable spread and 

 recurvature of the humeral and the femoral marginals. The anterior marginals 

 extend forward and upward, and the posterior extend farther back than the 

 caudal, which is narrow, convex, and curves down and forward at the lower 

 edge. The humeral indentation, on the third marginal, is shallow but the 

 groove from it to the middle of the first vertebral is decided, because of the 

 recurvation of the marginals behind it similar to T. clephantopus. The verte- 

 bral shields are broader than the costals; each has a high convex boss on the 

 middle, that on the fifth vertebral being especially prominent. Including 

 the areolar space on each costal there is a similar boss. On the plastron the 

 gulars are broad and subtruncate in front, swollen and rounded above the edge 

 and rounded on the angles. The pectorals are short, broad and in contact. 



