WICHITA FORMATION OF NORTHERN TEXAS 121 



element fairly well represented, Derby a cymbula being generally 

 present, and the pelecypod Myalina deltoidea rather abundant. 

 Another contrasting fauna has, as a rule, brachiopods absent or 

 greatly diminished, but is plentifully supplied with large nautiloids. 

 The faunas appear to have been contemporaneous, both occurring 

 throughout the formation, but in different localities. The nauti- 

 loid facies, however, is more prominent in the upper series of beds. 



The invertebrate remains of this region were studied by C. A. 

 White, 1 who considered them to be Permian. A map on which 

 the localities were shown was prepared for the Fifth Annual Report 

 of the Texas Geological Survey, but never published. 2 



The collections of vertebrates, which in past years have attracted 

 so much attention, were made in the adjoining portions of Baylor 

 and Archer counties. Cope, who first studied them, considered 

 them to be of Permian age. A description of the localities where 

 these remains were discovered has only recently appeared in print. 3 

 From this description, which is not accompanied by a map, it ap- 

 pears that no fossils were obtained east of the middle of Archer 

 County. In late years interest in the vertebrate remains of the 

 Wichita formation has been renewed and much new material has 

 been obtained, more particularly through the labors of Williston 

 and Case. The results of their investigations have appeared in 

 various papers. 



The plant remains from this region have been studied by 

 Fontaine and White 4 and by David White. The last named spent 

 several days in the field in 1909 and collected considerable material 

 from two near-by localities, one, two and one-half miles south of 

 Fulda, and the other four miles southeast of that place. As pro- 

 visionally identified this material is as follows: 5 



1 C. A. White, U.S. Geological Survey Bulletin 77 (1891). 



2 Transactions of the Texas Academy of Science (1897), 95. 



3 W. C. Cummins, Journal of Geology, XVI (1908), 737-45. 



♦ I. C. White, Bulletin of the Geological Society of America, III (1892), 217-18. 

 Study based on identifications by W. N. Fontaine. 



s No. 1: Cassil Hollow, two and one-half miles south of Fulda, Texas. No. 2: 

 Breaks of the Little Wichita, one-half mile south of the river, and four miles southeast 

 of Fulda, Tex. The beds are just over the bone-bearing limestone. The species 

 in bold-faced type are characteristic of the Permian. 



