The Pleistocene sediments of central Michigan include old lake deposits, low morainal hills, intermorainal deposits and fossil beaches. These provide numerous opportunities for burial and preservation of large vertebrate remains. Pollen spectra from sediments associated with two mastodons, Mammut americanum, found in Gratiot County, are presented. A radiocarbon date (10,700 + 400 years B.P.) from one of mastodons, plus a pollen diagram from burial site, provide a partial picture of late glacial flora of central Michigan. An attempt is made to correlate pollen spectrum from radiocarbon-dated mastodon with pollen diagram from burial site in order to establish time-stratigraphic relationships of vegetational remains. A pollen spectrum from a mammoth, Mammuthus jeffersoni, from Genesee County is also reported. These pollen analyses establish presence of a spruce and pine forest in central Michigan during period when these probiscidians died. Pollen analysis is supplemented by identification of plant and animal macrofossils present in sediments directly associated with mastodon bones. DESCRIPTION OF SITES Mastodon remains were discovered on William Pitt farm in S /2 NWV4 sec. 22, T. 12 N., R. 4 W., Gratiot Co., Michigan, early in present century. The fossil remains were originally described by MacCurdy (1919) and have since been deposited in Alma College Museum. According to MacCurdy, remains were in surface layers of a gravelly outwash, and not in contact with muck. The fragments were scattered and apparently disturbed by The site was revisited but exact location could not be found (Fig. tA). The area is farm land and surface features have been changed somewhat since mastodon was first discovered. Sediments were removed from mental foramen of right lower mandible for pollen analysis. In 1909 additional mastodon remains were discovered on Albert Smith farm, six miles southeast of Alma, in Emerson Township, Gratiot Co. (SW',4 NE,4 sec. 17). MacCurdy (1919) stated that the bones were lying on a gravelly bed, and were covered over by marl, which was in turn covered by about two feet of vegetable deposits, now largely turned to muck. The bones were scattered about, and some of them show some signs of wear from action of water. . . . The presence of marl served to protect bones from disintegrating action which might have been caused by overlying vegetable decay. This site was revisited and located as accurately as possible (Fig. 1B). The area is a fiveto-six acre basin having a ditch running along north side (the 1 Present address: Department of Botany, University of Minnesota, Minneapolis 14, Minnesota.