84 CONTRIBUTIONS TO PAL^ONTOLOGY 



coUections of the U. S. National Museum, where they were kindly made available to 

 me for the present study. Mj' own larger collections of plants from the tj^De Lance 

 werc obtainod during two weeks of the field season of 1936 and five weeks of 1938. 



As is shown in figure 1, the type locaUty of the Lance formation is in eastern 

 Wj-oming in the north-central part of Niobrara County (formerly the eastern part of 

 Converse County). It is referred to generally as the Lance Creek area and is the 

 location of the well-known Lance Creek oil field.' The area hes within a radius of 

 5 miles northward of the town of Lance Creek and is 25 miles north-northwest of 

 Lusk, Wyoming. 



The study of the Lance flora is a continuation of my program on Upper Cre- 

 taceous floras of the Rocky Mountain region, conducted under the auspices of the 

 Carnegie Institution of Washington and Princeton University. For their competent 

 assistance in the field I am indebted to H. H. Sharkey, K. M. Waage, F. D. Boice, 

 and J. S. Shirk, students at Princeton University, and J. S. Eddy, of LawTenceville 

 School. Suggestions and technical advice have been given by Dr. John B. Reeside 

 and Dr. Roland W. Brown, of the U. S. Geological Survey. Herbarium material 

 has been freely consulted at the New York Botanical Garden, whose stafT has been 

 most hclpful in offering suggestions regarding the systematic position of the fossil 

 plants. For his constructive criticism of the manuscript I am particularly indebted 

 to Dr. Ralph W. Chaney, of the Universitj^ of Cahfornia. 



EARLIER WORK IN THE AREA 



The Lance Creek area was first brought to scientific attention by Hatcher,^ who 

 had coUectcd a largc suitc of dinosaur remains there between 1889 and 1895. Before 

 the pubhcation of Hatchcr's papcr Marsh had described several species of Triceratops 

 (originally called Ceraiops) and other vertebrates from Hatcher's collections; he had 

 failed, however, to specify the locahtj'^ from which these specimens had been ob- 

 tained, other than that they were "from thc Laramie" or "from the Ceratops beds of 

 Wyoming." ^ It romainod for Hatchor to locatc the area, and to describe in detail 

 the Hthologic charactors and skotch thc areal boundaries of the beds which had 

 yieldod dinosaur remains. Regarding the stratigraphic position of the "Ceratops 

 beds," Hatcher statcd: " All the bcds of the entirc section arc conformablo, and bear 

 evidence of a continuous doposition, from tho Fort Picrre shales up through the Fox 

 HiUs sandstonos and tlic ovorlying frosh-water Ceratops bods." * Hatchor subse- 

 quently pubUshcd two othor short papors ^ which mcntioned the Lance Crock area, 

 but did not add any data pertinent to the present report. 



At about the same time, Stanton and Knowlton visitcd the Lance Creek area 

 and made collections of invertebrates and plants from both the "Ceratops beds" and 



'Hanpock, E. T., U. S. Geol. Surv. BuU. 716, 91-122. 1921. Emcry, W. B., Araer. Assoc. Petroleum Geologists, 

 Structure of Typical American Oil Fields. vol. 2, 604-61.3, 1929. 



» Hatchcr. J. B., Amcr. Jour. Sci., 3d ser.. vol. 45, 135-144, 1893. 



» Marsh, O. C, Amcr. Jour. Sci., 3d ser., vol. 37. 334, 1889; ibid., vol. 38, 81, 177, 501, 1889; ibid., vol. 39, 422, 1890; 

 ibid., vol. 41, 167, 1891; ibid., vol. 43. 249. 1892. 



« Hatchcr, J. B., op. cit., 139. 1893. 



•Hatchcr, J. B., Amcr. Naturaliet, vol. 30, 112-120, 1896; Amcr. Gcologist, vol. 31, 369-375, 1903. 



