310 ME. G. A. BOULENGEE ON AN EXTINCT 



up than the right ; the right postzygapophysis of the first caudal vertebra is abortive, 

 its facet being sessile and directed upwards; that of the second vertebra is less 

 developed than the left ; the other vertebrae being nearly symmetrical. 



In specimen C the right postzygapophysis is the more developed on the second 

 caudal vertebra, the left on the third and fourth. 



It is therefore clear that in these Tortoises the asymmetry of the caudal vertebrae is 

 subject to much individual variation, and that the identification of single vertebrae 

 cannot be attempted by means of this character. 



5. Pectoral arch. — The complete pectoral arch of a specimen which, judging from 

 the size of the bones, must be the one of which Mr. Last states he found most of the 

 bones, that is to say, the female previously noticed, is preserved. The coracoid is free 

 from the scapula, which measures (from the proximal extremity of the suture with the 

 coracoid) 17J centim., the acromial process (so-called precoracoid) measuring (likewise 

 from the suture with the coracoid) 9 centim. Length of coracoid 11 centim., greatest 

 width 9. These proportions agree very closely with those of T. elephantina. 



Besides these bones, a smaller right coracoid is preserved. 



6. Pelvis. — This is represented by the ischia of a large specimen, and the ilia and left 

 pubis and ischium of a smaller specimen, no doubt the female of which shell and bones 

 were found associated. In general configuration, and especially in the narrow bridge, 

 they agree with T. elephantina. The surface of the ilium which articulates with the 

 sacrum is directed more upwards than inwards, thus differing from the specimen of 

 T. elephantina with which I have compared it, and approaching the arrangement 

 described by Vaillant. 



7. Limb-bones. — Numerous carpal and tarsal bones and phalangeals and long bones 

 belonging to at least six specimens : — 



A. The largest (femur measuring 20 centim.) : left femur, right tibia, and left fibula, 



B. A smaller specimen, probably the female (femur 16^ centim.): right humerus, 

 right and left radius, and right ulna ; right and left femur and right tibia and fibula. 



C-F. Eight radius ; two right tibise ; four left tibiae ; one right and one left fibula. 



There are also a few bones, apparently dermal ossifications from the limbs, which I 

 am unable to determine with precision, having been unsuccessful in finding anything 

 similar with which to compare them. 



Now that most of the bones have been identified, it will perhaps be possible to mount 

 the skeleton of the female specimen found undisturbed by Mr. Last, and to exhibit it 

 in that condition in the Geological Galleries of the British Museum. The neck will, 

 however, have to be omitted. 



