294 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.48. 



clays. The section is discussed by Owen in the first volume of the 

 Geological Survey of Kentucky (p. 22) and the plants were briefly 

 described by Lesquereux in the American Journal of Science for 1859 

 (ser. 2, vol. 27, pp. 364-365). 

 The following species were enumerated: 



Quercus virens (Michaux). Osenothus americanus% (Linnaeus) 



Castanea nanal (Muhlenburg) . Carya olivseformis (Nut tall) . 



TJlmus alatal (Michaux). A corns calamus (Linnseus). 



TJlmus sp. Gleditschia triacanthos (Linnseus) . 



Planera gmelini (Michaux). Catkins of Alnus or Be tula. 

 Prinos integrifolia (Elliott). 



These are all still existing species and indicated according to Les- 

 quereux that the beds were of Pleistocene age. (See his remarks on 

 this point on pp. 360 and 366). 



Many years subsequent to the visit of Owen and Lesquereux, R. H. 

 Loughridge made an exhaustive study of western Kentucky and pre- 

 sented his results in his Report on the Geological and Economic fea- 

 tures of the Jackson Purchase Region. 1 Good accounts of both the 

 Hickman and Columbus Bluffs are given, the former in a graphic 

 section on page 38 and the latter on pages 46 and 218. Loughridge 

 mentioned no vegetable remains at the Hickman Bluff except sub- 

 fossil cypress knees in the recent river sediments and regarded the 

 deposits as constituting the oldest known Eocene of the embayment 

 area, giving to them the provisional name of the Hickman group. He 

 mentioned leaves from the Columbus Bluffs, but apparently made no 

 collections and assigned the deposit containing them to the "Lignitic" 

 (roughly corresponding to the Wilcox as now understood) . 



During the years 1903-1906 L. C. Glenn made a study of this area, 

 his results forming Water Supply Paper No. 164 of the United States 

 Geological Survey. He collected a few fossil plants from the exposure 

 just north of Columbus and discovered and collected fossil plants from 

 the Hickman bluff. These two collections were examined by F. H. 

 Knowlton, who stated 2 that the Columbus collection contained two 

 species of Quercus and a species of Salix; the Hickman collection "a 

 Salix, Menispermum canadmseh. 3 and Tecoma radicansJj., or something 

 near it." Both deposits were regarded as of Pliocene age. Glenn, 

 while he recognized the possibility of these leaf-bearing beds being 

 younger than the Wilcox, placed them in the upper part of that divi- 

 sion of the Eocene, concluding that he did not have " sufficient 

 stratigraphic evidence for such a separation." The present writer 

 did not have an opportunity of visiting these outcrops until the sum- 

 mer of 1913. While there is considerable variation in the height of 

 the bluffs and in the lithologic character of the beds, the following some 



i Geol. Surv. Ky., 1888. * Water Supply Paper No. 164, p. 38. 



