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 the ground with surprising rapidity. If unable to escape when pursued, its hard, stout tail and head are turned under to protect the lower side of the body where there are no scales. The three-banded species (Fig. 366) lives in Argentina. Compare the ears and tail of the two species; give reasons for differences. Why are the eyes so small? The claws so large? Order. Why?.

of Texas and Mexico. (Dasypus novemcinctus.) It is increasing in numbers; it is very useful, as it digs up and destroys insects. (See Fig. 347.)

(Tolypeutes tricinctus).

Insect Eaters.—The soft interior and crusty covering of insects makes it unnecessary for animals that prey upon them to have flat-topped teeth for grinding them to