1903.] NATURAL SCIENCES OF PHILADELPHIA. 543 



texas keptiles and their faunal relations, 

 by arthur eravin brown. 

 The Reptiles of Pecos. 



The town of Pecos, Texas, lies on the west bank of the river bearing 

 the same name, at an elevation of about 2,800 feet. The high plain 

 surrounding it and stretching west to the Rio Grande is much broken 

 by irregular mountain ranges of considerably greater height. 



The rainfall at Pecos does not exceed fifteen inches. The mean 

 annual temperature is 60° Fahr., and the winter minimum about 18°. 



During the past four years forty-eight species and subspecies of 

 living reptiles have been sent to the Zoological Gardens by Mr. E. 

 Meyenberg, of Pecos, all of which were collected in the neighborhood, 

 with the exception of a few from the Da.vis Mountains, some fifty miles 

 southwest. Many of these are little known and as I am aware of no 

 published list of similar extent from this region, they are here 

 enumerated. 



OHELONIA. 



Cinostemum flavescens (Agass.)- 



Platythyra flavescens Agass., Cont. Nat. Hist, of U. S., I, 430, PL V, figs. 



12-15. 

 (?) Cinostemum flavescens Coues, Wheeler Survey W. of 100th Mer., p. 



590, PI. XVII. 



Sufficient material is not available for full determination of the 

 mud-turtles of the Mexican border, and identification of the present 

 species must be made upon slight clues, for no published description 

 of it exists beyond the mention of a few characters considered by 

 Agassiz to be generic. These appear to apply to four turtles received 

 in September, 1901, from Pecos. In addition, I have a similar one from 

 El Paso, collected by Messrs. Townsend and Barber, and there is a 

 sixth belonging to the Academy, collected at San Antonio, in 1903, by 

 Dr. H. A. Pilsbry. 



In form and scutellation these turtles approach C. 'pennsylvanicwn. 

 The El Paso specimen is 130 mm. in extreme length of shell and 97 in 

 greatest breadth, a size rarely, if ever, reached by the eastern species. 

 In adult males the shell is depressed on the dorsal line and shows traces 



