Tertiary faunal horizons in the Wind River Basin, Wyoming, with descriptions of new Eocene mammals. Bulletin of the AMNH ; v. 28, article 21.

p. 235-251, [5] leaves of plates (1 folded) : ill., map ; 24 cm.Includes bibliographical references."1. The Wind River Basin is covered throughout the greater part of its area with beds of the Wind River group, pertaining to the Lambdotherium zone. 2. Mammalian remains are extremely rare or absent from these beds except in two localities in the northern and northeastern part of the basin, viz., along Alkali Creek and between Muddy Creek and the Owl Creek Mountains. 3. Lying alone the northern border of the Tertiary deposits in the northeastern corner of the basin, between the foot hills and the Lambdotherium beds, apparently older than the latter and with the best exposures along Cottonwood Creek, is a series of strata of 350 feet or more, containing a fauna intermediate between the Lambdotherium zone and the Coryphodon zone of the Big Horn Wasatch, the genera being all common to both zones. 4. Along the southern border of the basin, on the divide between Sweetwater River and Beaver Creek, there is exposed a thickness of 1,100 feet of Tertiary, a remnant of deposits which undoubtedly extended over a large part of the basin at one time. Three distinct faunal levels, as indicated by mammalian fossils, are exhibited, Lower Eocene, Upper Eocene, and Lower Oligocene, the levels being correlated with (1) the ?Coryphodon Zone of the Wasatch, (2) the ?Diplacodon Zone of the Uinta, and (3) the Titanotherium Zone of the White River. An unconformity exists between the Eocene and Oligocene, but no break in sedimentation was detected in the Eocene series. 5. Between the Coryphodon and Diplacodon levels are several hundred feet of unfossiliferous beds, the lower part of which pertain probably to the Lambdotherium zone of the Wind River group, and the upper part possibly to the Middle Eocene faunal zones of the Bridger Basin"--P. 247