1894.] NATURAL SCIENCES OF PHILADEL,PHIA. 65 



been determiued by Prof. Brown as follows: — 7:!^.rof///ra tcmna, 

 Gnjphiea pitcherii, Ostrea siibovata, Ostrea fcrenidhnarf/o, Ostrea 

 sp., Citculkca tenuinalis, Neithea occidentaUs, Plieatula incongrna, 

 Trigonia sp., Trigonia emoryi, Turrifella mriathngranulata, Schhm- 

 bdchla peruviana. 



We found also the following vertebrata: Lam)ia No. 1, Lamna 

 No. 2, Lepidotid scale, Uranoplosiis ardatus, U. flectidetis, Coelo- 

 dtis hrownii, Plesiosanrus vertebrae, crocodile fragments, and frag- 

 ments of a tortoise. 



The three species of Pycnodont fishes were new to science, and 

 they have a Lower Cretaceous facies. Plesiosaurvs is represented 

 by dorsal vertebrae only, but these are not of the Upper Cretaceous 

 type. I have never found Lepidotid fish remains in the Upper Cre- 

 taceous of North America, while they are characteristically Lower 

 Cretaceous and Jurassic in Europe. The only occurrence of Lepi- 

 dotid fishes so far recognized in N. America, is based on some teeth 

 sent by Mr. Charles H. Sternberg in the Dakota sandstone of Kan- 

 sas, and on the new species, Macrepistius arenatus, from the Trinity 

 bed of Texas discovered by Prof. R. T. Hill. (See Journal of the 

 Academy Vol. IX, Part 4). The crocodilian remains are unde- 

 terminable. 



Below this formation, which is of a strong yellow color and about 

 twenty-four feet thick, is a stratum of marls, black above, whitish in 

 the middle, and buff below, of about equal thickness with the lime- 

 stone. The black color is due to carbon, which is some places forms 

 thin lavers of impure coal. This formation contained no fossils by 

 which its age could be determined, and thus stood in strong contrast 

 with the cretaceous above it, and agreed with the red beds of the 

 Permian below it. Between the black marl and the cretaceous there 

 intervened at some points a shallow bed of sand, usually coarse, and 

 reaching in places a thickness of six feet. Its color is yellow, varied 

 with horizontal red streaks. The age of the marine Cretaceous beds 

 corresponds, according to Prof Brown's determination, with the 

 Comanche Peak terrane of the Texas geologists. The tract first ob- 

 served lies about five miles northwest of Fort Supply, and is of 

 limited extent, being cut off to the north by the drainage of the 

 Cimarron River, and to the south by the drainage of the North Fork 

 of the Canadian. Its horizontal extent cannot exceed fifty s([uare 

 miles. We examined another and more limited area of the 



