GLYP'TODON (Neo-Lat., from Gk 7Xvvr6s, glyptos, carved + Moth, odous, tooth, in allusion to the sculptured grinding surface of the teeth). A gigantic extinct edentate mammal allied to the armadillo, and of which fossil remains are found in the Pleistocene deposits of South America, and less commonly in Mexico, Texas, and Florida. The animal had a solid carapace made up of mostly hexagonal plates arranged in transverse rows, like those of the armadillo, but solidly united, so that the creature was unable to curl up.
These bony plates were often ornamented by grooves or tubercles, and were covered by horny epidermal scales. The tail also was encased in a sheath of strongly nodular bony plates. The head likewise had, in some species, a coat of mail of small plates. The skull is high, narrow, and short, with a peculiar long process descend ing from the zygomatic arch. Both the jaws have eight molar teeth on each side, each of which is divided into three vertical prisms by two deep lateral grooves, and the form of the crown sculp turing is very peculiar. The legs are heavily
built, the feet large, and the firgers are short, and armed with thick hoof-like claws. The latter character shows that the animal could not have been a burrower like the armadillo. The best known species is Glyptodon clavipes of the Pleistocene beds of Argentina, which attained a length over all of about seventeen. feet. An al lied genus is Dndicurus, of even larger size than Glyptodon, with a smooth carapace pierced by many cavities, and a longer tail formed of five or perhaps six movable rings, terminated by a club-shaped tube, which seems to have borne mov able spines or bosses at its extremity.
Consult Lydekker, "The Extinct Edentates of Argentina," in Anales de Muse° de la Plata, Paleontologic Argentina, vol. iii., part ii. (La Plata, 1894). See EDENTATA.