419 



2313. The right femur of the same Armadillo. 



The shaft is bent inwards above the base of the third trochanter. There is a small ossifi- 

 cation at the middle of the outer semilunar cartilage. The tibia and fibula are attached at 

 both ends to a similar common epiphysis. 



2314. The left femur of the same Armadillo, in longitudinal section. 



2315. The exoskeleton of the same Armadillo, forming the supracranial casque and 

 the carapace. 



The latter has three of its middle segments moveable, allowing the inflection of the trunk 

 and its complete protection by the approximation of the anterior to the posterior division of 

 the carapace. 



The following parts of the same skeleton of the Dasypus minutus were 



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



2316. The two rami of the lower jaw, in each of which there are nine alveoli : the 

 first and smallest is situated on the symphysis. 



2317. The atlas of the same Armadillo. 



It has both parapophysis and diapophysis. The neural arch has two perforations on each 

 side ; the hinder one for the nerve, the front one for the vertebral artery. 



2318. The axis and two succeeding cervical vertebrae. 



The confluence is complete with the third vertebra, and is partial between the third and 

 fourth vertebrae. 



2319. The three remaining cervical vertebrae. 



The neural arch is incomplete above in the sixth, and the harmonia between the right 

 neurapophysis and centrum still remains in the sixth and seventh vertebrae. The transverse 

 process of the seventh is imperforate. 



2320. The first dorsal vertebra, which is characterized by its long and slender spine. 

 The nerve perforates the base of the neurapophysis. 



2321. Three succeeding dorsal vertebrae, showing the same direct perforation below 



3n2 



