76 



GUIDE TO THE FOSSIL MAMMALS AND BIKDS. 



Wall-case 



26. 



Table-case 



14b. 



Case Z. 



lapping cross-bands which enable the surviving armadillos 

 to roll into a ball when attacked. Glyptodon (Fig. 70) is 

 one of the best known genera, and owes its name (" sculptured 

 tooth") to the circumstance that hard and soft portions 

 alternate in the teeth, thus imparting a sculptured appearance 

 to their grinding surface. The actual armour of a fine 

 specimen is mounted, with a plaster cast of the skeleton, in 

 Case Z. As here exhibited the total length of the animal, 

 measured along the curve of the back, is 11 feet 6 inches ; 

 while the body shield or carapace measures 7 feet in length 

 by 9 feet across. The armour obviously consists of small 

 bony rosettes or bosses compacted together, and it must have 

 been originally covered with a thin outer skin. There is a 

 little shield on the top of the head ; and the covering of the 

 tail is arranged in successive, overlapping rings. At times 

 of danger, the animal would probably be able to draw up its 



Pig. 71. — Portion of tail-sheath of Hoplophorus, from the Pampa Forma- 

 tion of the Argentine Republic ; one-quarter nat. size. (Wall-case 26.) 



legs close to the body, so as to rest its carapace on the 

 ground, while its armour-plated head would be bent down- 

 wards in front. The massive tail must have moved freely 

 behind the carapace, and in one genus, Daedicurus, the solid 

 end of the tail-sheath is somewhat expanded to bear a cluster 

 of bony bosses which would give it the aspect of a powerful 

 club (see Wall-case 26). Hoplophorus is a smaller elongated 

 animal having the end of the tail-sheath without rings 

 (Fig. 71). It is illustrated by a good series of specimens in 

 Wall-case 26. 



The earlier remains of armadillos from Patagonia, as 

 Tal L4b 0aBe snown by the collection in Table-case 14b, represent animals 

 much smaller than those from the Pampa Formation, and 

 some of them have a banded carapace like that of the living 

 armadillos. It must, in fact, be understood that the tree- 

 sloths of the present South American forests and the 



