GIGANTIC EXTINCT ARMADILLOS. 



H3 



naked, whence its name, Dasypus gymnurus. The little three-banded 

 species has the upper face of the tail covered with relatively thick 

 plates. In living specimens I have also noticed that the ears, though 

 very thin, were covered with thin and minute (usually polygonal) scales, 

 both inside and out. 



Studies of the feet of the Hoplophoridm show that they can be 

 divided into two well-defined groups : the first, to which the animal 

 represented in the figure belongs, has four claw-bearing toes on the 

 fore-legs, and four hoof -bearing toes on the hind-legs ; the second group 

 has four claw-bearing toes on the fore-legs, and five hoof-bearing toes 

 on the hind ones. As the figure shows, and which is fully supported 

 by the osteology, the hinder extremities are proportionally more mas- 

 sive and longer than the fore ones, which fact, together with the enor- 

 mously expanded pelvic bones, shows that the creature perhaps raised 

 the fore-part of the body into a more or less nearly vertical position 

 with the help of its tail to reach the leaves of plants upon which it fed, 

 as did its huge congeners, the extinct sloths. This view is favored by 

 the flattened condition of the tail-case or armor toward its extremity, 

 perhaps from the pressure to which it was often subjected from below 

 while in the bipedal position. This also explains the use of the belly- 

 shield to have been to afford protection against enemies from below 

 while in such an attitude, as the animal, because so well protected 

 otherwise, was probably less favored in respect to sight and hearing. 



The carapace was supported for nearly half its length upon the 

 haunch-bones (ilia and ischia), as well as by the strong, longitudinal, 

 median, bony crest rising from the lumbar and sacral vertebra?, consist- 

 ing of their united neural or spinous processes. The carapace rested 

 directly on these bones, and was joined to them by suture, as the 

 roughened and expanded surfaces for such juncture clearly show. The 



-cc 



A, transverse section of the "dorsal tube" of Panochthus tvberevlatus : a and b, lorarnina for 

 spinal nerves; v, vertebral centrum. One-sixth natural size. (After Bnrmeister.) 



B, transverse section through a portion of the carapace and middle of one of the vertebrae (dorsal 

 tube) of a salt-water terrapin: c, carapace; b. proximal extremity of ribs; a a, situation of 

 foramina for the exit of spinal nerves ; v, vertebral centrum. Central dark spaces in A and B 

 show the forms of the neural or spinal canals in section. (Original.) 



C, side-view of a dorsal vertebra of a European tortoise : a indicates the position of lateral fora- 



mina a a in B. Other references same as in B. (After Bojanus.) 



entire union of the lumbar and sacral vertebra? into a hollow bony bar, 

 and the union of this to the lateral elements of the pelvic arch, together 

 with the union of both by suture with carapace, rendered any lateral 



