The Pleistocene of North America / and its vertebrated animals from the states east of the Mississippi River and from the Canadian provinces east of longitude 95°

by Oliver Perry Hay

ILLINOIS.

(Map [24].)

1. Alton, Madison County.—In the collection of fossils made in the region about Alton by William McAdams, a list of which will be given on page [339], is a single upper right molar, the first or second, which belongs to this genus. The tooth has McAdams’s No. 11. To the base of the tooth a mass of very hard matrix adheres and a part of the grinding-surface is covered by the same material. The tooth is likewise somewhat shattered. The length of the tooth is 19 mm., the width across the anterior lobe 13.5 mm.

From the materials at hand it is not possible to determine to what species the tooth belonged. It is referred provisionally to Rangifer muscatinensis. This tooth differs from other Rangifer teeth observed in having the front of the protocone, at its base, less fully rounded out, and in that the mesostyle, on the inner face of the tooth, widens more extensively as it approaches the base than in any other species observed. Nevertheless, the width of the mesostyle varies in species and individuals.