92 EDENTATA. 



claws. In the pes fhe first and second digits are aborted, the third 

 digit being furnished with a very large curved claw, like that of 

 Megatherium. All the species in the Museum have an entepi- 

 condylar foramen to the humerus. 



Scelidotherium leptocephalum, Owen\ 

 This is the type species. The cranium is of moderate width, 

 the nasals and maxillae are of remarkable length, that of the former 

 being equal to at least half of the total length of the superior 

 surface of the cranium. The lachrymal is not very prominent, and 

 the interdental portion of the palate of moderate width. 



The portion of the mandible in advance of the teeth is much 

 elongated, and is nearly twice the length of the dental series, its 

 superior border being nearly horizontal. The scapula has a straight 

 anterior border ; the femur is short and wide ; and the external 

 trochlear ridge of the astragalus for articulation with the tibia de^- 

 pressed. In the structure of the facial part of the cranium and 

 of the astragalus this species approximates to Ilyrmecophaga. 

 Hah. South America (Patagonia and Argentine Eepublic). 



M. 3583. Cast of the imperfect skull. The original was obtained by 

 Darwin from the Pleistocene of Punta Alta, Patagonia, 

 and is preserved in the Museum of the Eoyal College of 

 Surgeons (No. 3506). Together with the associated speci- 

 mens it forms the type of the species, and is figured by 

 Owen in the ' Zoology of the Voyage of the Beagle,' 

 pis. xxi.-xxiii. 

 Presented by the Council of the Royal College of Surgeons, 



37308. The cranium, imperfect anteriorly and posteriorly ; from the 

 {Fig.) Pleistocene of the Ilio Plata, Argentine Pepublic. This 



specimen (woodcut, fig. 19), which agrees very closely 

 with the one figured by P. Gervais in the ' Mammiferes 

 Possiles de I'Amerique Meridionale,' pi. xi. fig. 1, is de- 

 scribed and figured by the present writer in the Proc. 

 Zool. Soc' 1886, p. 493, pi. xlvi. The length of the nasals, 

 which are imperfect anteriorly, is 0,270 ; all the teeth are 

 in situ. Bravard Collection. Purchased^ 1854. 



37309. The mandible, imperfect posteriorly; associated with the 



preceding specimen. This specimen, which is noticed by 

 the present writer in the paper cited, accords with the 

 one figured by Gervais, op. cit. 



Bravard Collection. Purchased, 1854. 

 ^ Zoology of the Voyage of the ' Beagle,' pt. i. p. 73 (1840). 



