Mammals of the Pleistocene Slaton Local Fauna of Texas

Abstract

Reinvestigation, including washing of matrix, in the old Slaton quarry, Lubbock County, Texas, yielded remains of 30 kinds of mammals. A white- tailed prairie-dog, Cynomys vetus, is reported from Texas for the first time. Numer- ous good specimens of the extinct water rat. Neofiber leonardi, show the distinctness of that species. Abundant material permits detailed description of two extinct species of horses. The vertebrate fauna indicates a mild climate with extensive grasslands and scattered trees and thickets in the vicinity of the fossil site. The fauna is prob- ably of early Illinoian age. The Slaton quarry, source of the Slaton local fauna, is located on the north side of Yellowhouse Canyon, approximately five miles north of Slaton, Lubbock County, Texas. Johnson and Savage (1955) credit Mr. Porter Montgomery with the original discovery of vertebrate fossils at the site, then known as the Smart Ranch, in 1941. Grayson E. Meade collected fossils in the gray Pleistocene clays of the old lake bed in 1942, for the West Texas Museum, at Lubbock, and the Texas Bureau of Economic Geology, in Austin. Meade recognized the unique nature of the fauna and described an antilocaprid (1942) and a water rat (1952) from the locality. In the latter publication he formally named the Slaton local fauna. Evans and Meade (1945) gave a brief account of the Pleistocene deposits that yielded the Slaton local fauna, and a faunal list. The Slaton local fauna has been mentioned in print from time to time (eg. Hibbard, 1958) but no detailed account of the vertebrate fauna has been published. Meade's account of the water rat from the Slaton quarry, a species otherwise unreported from the Pleistocene of Texas, stimulated a reexamination of the site during 1963 and 1964. The old Smart Ranch is now the property of Mr. Allen Wallace, and I am deeply grateful to Mr. Wallace for access to the deposits, the use of his power machinery in some of the excavating, and other favors. With the aid of tractors we were able to uncover some rich fossiliferous deposits, and 13 tons of gray clay matrix were removed to Wichita Falls and washed and sorted to obtain the microfossils present. The clay matrix is extremely fossiliferous. When washed through ordinary fly screen, the retained solids are mostly fossils. Most of the fossils are of plants and mollusk shells. Chips and bits of bones of large mammals are common, while remains of reptiles, amphibians, birds and small mammals are rare.