THE 



JOURNAL OF GEOLOGY 



OCTOBER-NOVEMBER, igio 



NEW PERMIAN REPTILES: RHACHITOMOUS 

 VERTEBRAE 



S. W. WILLISTON 

 The University of Chicago 



On the last day of field work by the University of Chicago 

 Expedition to the Permian of Texas in the autumn of 1909, Mr. 

 Lawrence Baker of the expedition discovered on Craddock's Ranch, 

 about six miles from the town of Seymour, a remarkable deposit 

 of fossil bones. All that could be done at the time was to collect 

 a quantity of the loose bones from the surface. Work was begun 

 upon the deposit by Mr. Paul Miller the present season, and, 

 although the results obtained were not what had been hoped for 

 and confidently expected, perhaps two hundred or more specimens 

 were obtained. The bones were, found almost invariably isolated, 

 but in the most perfect preservation, for the most part entirely free 

 from matrix; others were more or less covered by, or cemented 

 together in, nodular concretions. The clay beds in which they were 

 found, because of their usual barrenness, had never been thoroughly 

 examined by previous collectors, and the bone deposit, though 

 but a few hundred feet away from a well-traveled road, had been 

 overlooked. 



An incomplete examination of the material obtained shows a 

 great variety of genera, not the less interesting because of their 

 association. It includes various shark spines; a small quantity of 

 Diplocaulus remains; at least three other forms of unidentified 



Vol. XVllI, No. 7 585 



