GIANT SLOTHS AND ARMADILLOS 293 
Armadillos belong, with sloths and ant-eaters, to the same 
family of so-called toothless animals (edentata) with no front 
teeth, though one or two forms really are toothless. Those of 
the present day have their bony armour divided up into a series 
of bands, so that they can roll themselves up, more or less, into 
balls. They burrow under the ground, where they get their food 
to a certain extent, and live a safe life, protected by their casque 
of mail. Their only enemies seem to be the monkeys, and one 
of the tricks of the young monkeys in the American forests is, 
when they find an armadillo away from home, to pull its tail 
unmercifully, and try to drag it about. Snakes cannot hurt them. 
Mr. W. H. Hudson, in his most interesting book, A Naturalist in 
La Plata, narrates how he watched an armadillo kill a snake and 
then devour it. 
If we examine the anatomy of the armadillo, we shall find that 
its bones greatly resemble those of the sloth, but still there are a 
few differences. It is a burrowing animal, and therefore requires 
great power of scratching and tearing the ground. Why the 
colossal forms of armadillo should have become extinct and only 
small ones survived to the present time, is one of the many and 
perplexing problems presented by the study of extinct animals. 
One would have thought from its size and strength that the 
Glyptodon had been built, like Rome, for eternity.^ 
^ The reader who is interested in evolution is strongly recommended to read 
the very interesting and suggestive address of Dr. A. Smith Woodward, F.R.S., 
to the Geological section of the British Association, 1909 (Winnipeg Meeting). 
In this paper the writer speaks of the symptoms of old age in races. One of 
these is loss of teeth, shown in tortoises, birds, monotreme mammals of 
Australia, and in the Ichthyosaurs. Another is degeneration into eel-like 
forms, and another is a superfluity of dead matter in the shape of spines or 
bosses, armour plate, and big horns, like those of the Irish deer (Cervus 
giganteus). 
