43 



233. A corresponding molar tooth of a Megatherium. 



From Punta Alta, Bahia Blanea, Patagonia. 



Presented by Charles Darwin, Esq., F.R.S. 



The following specimens of the osseous remains of the Megatherium are 

 parts of one and the same skeleton, which was discovered in the bed of the Rio 

 Salado, with No. 218. Presented by Sir TV. Parish, K.H. 



The casts of these bones which are preserved in the Museum, bear the same 

 numbers as the original specimens, and are distinguished by the letter c. 



234. The atlas of the Megatherium. 



235. The spinous process and left posterior articular process of the axis or 



vertebra dentata of the Megatherium. The spine is much extended from 

 before backwards, and is moderately high, with a rough expanded poste- 

 rior margin and a broad obtuse bifurcate posterior extremity, which 

 slopes backwards so as to have overhung the third vertebra. 



236. The anterior end of the body with the odontoid process of the same ver- 

 tebra ; the lower part of the process presents an elliptical and slightly 

 convex surface, adapted to the articulation upon the body of the atlas. 



237- The body, transverse and inferior articular processes, of the third cervical 

 vertebra. 



238. The neural arch and spine of the third cervical vertebra. 



239. The body and spine of the fourth cervical vertebra. 



240. The fifth cervical vertebra. The spinous process is small, compressed, 



sub-triangular and vertical in position ; three transverse processes are de- 

 veloped from each side of the body ; the inferior one, which is extended 

 longitudinally beyond both the anterior and posterior surfaces of the 

 body, is flattened, the second is short and thick, and is developed from the 

 side of the vertebral foramen, the third is also a short and thick process 

 extending from the side of the anterior articular process. 



241. The neural arch and spinous process of the first dorsal vertebra: it is the 



highest and broadest spine in the whole vertebral region. 



g 2 



