s, 



Edentata — Armadillos. 



71 



In addition to the series of gigantic Ground-Sloths, we 

 may notice the several genera of extinct gigantic Armadillos, 

 also from the Pleistocene deposits of South America. 



These large extinct genera differed from the living species 

 of Armadillos in having their coat of mail composed of a single 

 piece, not divided up into a seizes of bands or segments, by 

 means of which the living forms are enabled, when attacked, 

 to contract the body into the form of a ball. In most of the 

 extinct species the carapace is composed of polygonal or quad- 

 rangular bony scutes, closely united by their sutures into a 

 solid buckler, and the caudal portion is enclosed in a complete 

 bony tail-sheath. The top of the head is also protected by 

 tessellated dermal plates of bone. 



Fig. 65.— Extinct Gigantic; Armadillo, Glyptodon clavipes (Owen), from the Pleistocene 

 deposits of Buenos Ayres, South America (much reduced). 



a, View of entire animal, r., Front end of carapace, c. Back view of same, d and n, 

 Upper and under side of skull, f, Section of tail showing caudal vertebrae inside the 

 bony sheath. 



(The caudal sheath represented in this figure probably belongs to Hoploplwrus.) 



Wall-oase, 

 No. 26. 



Table-case,. 

 No. 15a. 

 Glass-case 



a. 



N 



The cheek-teeth are sixteen in number, four above and four 

 below on each side, incisors not being developed ; they have two 

 deep grooves on either side dividing them into three nearly 

 distinct lobes. The facial portion of the skull is extremely short, 

 and the zygoma has a long descending maxillary process just 

 beneath the eye. 



The vertebral column beneath the carapace is almost entirely 

 anchylosed into a long tube, and is confluent with the under 

 surface of the dermal armour, to which the ribs are also united. 



