Mastodon

Elephant-like Tertiary mammal with tuberculated teeth. It surpa ed in size the existing elephant, and seems to have chiefly frequented temperate latitudes in both hemispheres. The species whose remains are most abundant in the U. S. is M. american us, also called M. giganteus and M. ohioticus. Its remains are usually found in swamps: the first, disinterred in Mo., was bought for the British Museum. An Mastodon american us. other, found at New burgh, N. Y., is in Dr. J. C. Warren's museum, Boston, Ma . The museum at Central Park, New York, State Museum at Albany, N. Y., Princeton Univ. Museum, Ohio State Univ., Rutgers Coll., Earlham Coll., and Field Columbian Museum, Chicago, each has a specimen. Over 20 species have been found represented in all continents. They begin in the Miocene and finally become extinct in the Pleistocene. Their tusks vary in curvature. The young and some adults had lower incisors. They have 6 molars, only 3 of which are in use at once, and the first three replaceable by a second set. The first molars have 1 or 2 ridges, the last 5 or 6, and the middle ones 3 or 4, according as the specimen is in the tri lophodont or the tetra lophodont series.