Armadillo
2 of the 6 encyclopedias on this shelf carry an entry for Armadillo. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
the Spanish-American name now imported into English, of various mammalia belonging to the order edentata, the family dasypodidæ, and its typical genus dasypus. The name armadillo, implying that they are in armor, is applied to these animals because the upper part of their body is covered with large, strong scales or plates, forming a helmet for their head, a buckler for their shoulders, transverse bands for their back, and in some species a series of rings for the protection of their tail. The fore feet are admirably adapted for digging, and the animal, when it sees danger, can extemporize a hole and vanish into it with wonderful rapidity. If actually captured, it rolls itself into a ball, withdrawing its head and feet under its strong armor. There are several species -such as the great armadillo, or tatu (dasypus gigas), the three-banded armadillo, or apara (D. apar), the sixbanded armadillo (D. sexcinctus), and the hairy armadillo (D. villosus). They feed chiefly on ants and other insects ARMADILLO and worms, and are peculiar to South America. It is also the name of a genus of crustaceans belonging to the order isopoda, and the family oniscidæ, the type of which is the well-known wood-louse. It is so called partly from its being covered with a certain feeble kind of armor; but chiefly from its rolling itself up into a ball after the fashion of the South American mammalian armadillos.
Aiton's Encyclopedia (1910)
an American mammal of the sloth family, noted for its defensive armor. There are at least four species, variously distributed from Texas to Argentina. The largest is three feet in length not counting the tail; the smallest is only five or six inches long. All armadillos are armed with strong claws, and dig rapidly, being able to escape pursuit by burying themselves in the ground before an ordinary pursuer can overtake them. Ordinarily the armadillo rests on the ground like a tortoise. When alarmed it raises itself up on the very tips of its long claws and scuttles about quite actively for a short time. The different species are variously covered with scales not unlike those of an alligator, and some species have the power of rolling themselves up into balls, so as to present a defensive surface at every point. Like the anteater, the armadillo lives chiefly on insects, worms, snails, lizards, fruits, and roots. The armadillo is related to the anteater, but its tongue cannot be protruded. The natives of South America eat the armadillo, but its flesh is offensive to the ordinary palate. Armadillo steaks are served in the restaurants of Buenos Ayres . Some travelers who affect to like them claim that they taste like spring chicken. See Anteater ; Sloth
What Has Changed in the Last Century
Collier's called armadillos "peculiar to South America" in 1921, and Aiton's in 1910 counted "at least four species" from Texas to Argentina; today about twenty species are recognised, and the nine-banded armadillo has pushed north from the Rio Grande through Texas into Kansas, Illinois and Virginia. The classification has also gone: the old order Edentata was broken up, and armadillos are now placed in their own order, Cingulata, related to sloths and anteaters within the group Xenarthra rather than being "of the sloth family". Two discoveries since made the animal famous in laboratories: the nine-banded armadillo normally bears identical quadruplets from a single egg, and it carries the leprosy bacterium, which made it the key research animal for a disease that will not grow in ordinary culture. Genetic work has since tied a small number of human leprosy cases in the southern United States to contact with wild armadillos.
Written for this edition, 2026.