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LOWEK MAMMAL GALLERY. 
latter being scarcely larger than a Rat. Both lead an entirely 
arboreal life and have the tail prehensile. 
The Armadillos, Dasypodidce, are remarkable for the thick 
plates of bone with which their bodies are covered, forming 
immovable shields across the shoulders and hips, the centre 
of the back being protected by a larger or smaller number 
of transverse bands of plates, joined to each other by flexible 
skin. The head and tail are also covered by a mosaic of bony 
plates ; but the belly and inner sides of the limbs are clothed 
only with soft skin. The fore-feet have a variable number 
of long and powerful claws, but the hind-feet always carry 
five rather small claws. In all the group teeth are present, 
generally = 28 to 38 in number, but in the Giant Arma- 
dillo amounting to = 80 to 100. These teeth are small 
and simple, with single roots. In the genus Tatusia alone 
a set of double-rooted milk-teeth precedes the simple single- 
rooted permanent ones, and traces of a milk-dentition have also 
been found in Dasypiis. The second and third, and often 
several of the other neck-vertebrse are welded together. The 
collar-bones, or clavicles, are well developed, and the whole 
fore-limb is enormously strengthened to support the huge 
digging-claws. 
The largest living species is the Giant Armadillo, Priodontes 
gigas ( 1381 ), measuring more than two feet in length ; while 
the smallest, rarest, and in many respects the most interesting, 
is the Pichiciego, or Fairy Armadillo, Chlamydopliorus trun- 
catus ( 1377 ), which has the outer shield attached to the hip- 
bones by peculiar bony processes. It leads an underground 
life. The Three-banded Armadillos, Tolypeutes (1373 to 1374 ), 
have the power of rolling themselves up into perfect balls, 
like Hedgehogs, the head and tail fitting into corresponding 
notches in the shield. Armadillos are ground-animals, able to 
burrow in the soil with surprising rapidity, either with the 
object of escaping danger or in search of their food, which 
consists of roots, insects, worms, reptiles, and carrion. They 
are found chiefly in the warmer parts of Central and South 
America, although a few range southwards into Patagonia. 
Fossil Armadillos are numerous in the Tertiary deposits of 
