HISTORY OF THE EDENTATA 



613 



very completely known. As a whole, this assemblage of arma- 

 dillos was very different from that of the Pleistocene, and only 

 a few direct ancestors of the latter have been fomid in the 

 Miocene of Patagonia ; no doubt, like the ancestral tree-sloths 

 and anteaters, they were then Uving in the warmer regions of 

 the north. Most of the Santa Cruz armadillos belonged to 

 aberrant types, of which no descendants have survived ; but, 

 nevertheless, they throw welcome Ught upon the developmental 

 stages of the suborder. 



These armadillos had the complete armoiir of head-shield, 

 carapace and taU-sheath, but the carapace had no anterior 



Fig. 292. — Skull of \PeUephiXus, Santa Cruz. Ameghino collection. 



buckler in any of the Santa Cruz genera, and in some there was 

 no posterior buckler, the carapace consisting entirely of trans- 

 verse, movable bands, as in the Pleistocene \Eviatus. In one 

 especially peculiar genus, ^Peltephilus, the head-shield was 

 remarkable; it was made up of large, polygonal plates, the 

 two anterior pairs of which were elevated into high, sharp 

 points, which must have supported horns, that were quite 

 large in proportion to the size of the animal. A 4-homed 

 armadillo, like a tiny rhinoceros in armoiir, must have been a 

 suflBciently bizarre object. 



