THE EDENTATA LORICATA. 339 



deeper surface to tlie ilia and iscliia, and arches over the 

 rump like a half dome. The tail may further be invested 

 by a series of incomplete bony rings and scattered scales ; 

 and scutes are distributed over the limbs. In one genus, 

 Chlamydophorus, the scutes are developed only in the pelvic 

 region. 



In the skull the premaxillse are well developed, and the 

 zygoma is complete. The mandibular ramus usually has a 

 well-developed ascending portion and coronoid process. 

 Clavicles are present. The fore and the hind feet rest 

 upon the ground evenly, and indeed the hind limbs are 

 usually plantigrade, or nearly so ; but, in the singular 

 genus Tolypeutes, the fore foot is supported upon the ex- 

 tremities of the long nails. The pollex is always present 

 in the fore foot, but the fifth digit sometimes becomes iiidi- 

 mentary. There are always five toes in the hind foot. 



In the genus Euphractes, each premaxilla contains a 

 single tooth, which, consequently, is an incisor. 



This group contains two divisions, the Dasypodidce and 

 the Ghjptodontidce ; both are South American, but the 

 former is chiefly composed of living animals, while the 

 latter only contains an extinct genus. 



The Dasypodidas are what are commonly known by the 

 name of Armadillos. In this division the thoraco-abdominal 

 shield, when present, as it is in all the genera except Chla- 

 mydophorus, consists of, at fewest, three, and, at most 

 thirteen, transverse movable zones of scutes. 



In the skull, the ends of the nasal bones project beyond 

 the level of the premaxillse, so that the nasal aperture looks 

 more or less downwards. The premaxillse have a consider- 

 able size, and articulate largely with the nasals. The 

 anterior part of the jugal arch offers, at most, a rudimentary 

 downward prolongation. The mandibtdar symphysis has 

 but a moderate length, and the posterior alveoli of the 

 mandibles do not extend along the inner face of the 

 ascending portion of the ramus of the jaw. 



The teeth of the upper and lower jaws alternate, and 

 hence their grinding surfaces wear down into ridges. 



