1887.] NATURAL SCIENCES OF PHILADELPHIA. 39 



ON THE CRETACEOUS FORMATIONS OF TEXAS AND THEIR RELATION TO 

 THOSE OF OTHER PORTIONS OF NORTH AMERICA. 



BY CHARLES A. WHITE. 



Published by permission of the Director of the U. S. Geological Survey. 



The true relations of the different Cretaceous formations which 

 have long been known to exist within the State of Texas to each 

 other, and to those which have been recognized in other portions 

 of North America, have not hitherto been satisfactorily known. 

 Several eminent geologists have written upon the subject, and 

 considerable diversity of opinion has prevailed among them. 

 The former impracticability of obtaining information by personal 

 observation over any considerable portion of that great region; 

 the destruction by the civil war of the work so well begun by 

 Dr. Bhumard, and the limited knowledge then possessed by any 

 one of the general geology of North America, were doubtless the 

 causes which prevented a satisfactory solution of this question. 

 Now numerous railroads traverse the State, the hostile tribes 

 which barred the progress of travelers have been quieted or 

 removed, and a good outline of the geology of the continent is 

 known. 



With the opportunity of availing myself of these advantages I 

 entered last year upon an investigation of the Texas Cretaceous, 

 placing the field work in charge of my chief assistant, Mr. Robert 

 T. Hill. In the latter part of the season I traversed the State in 

 various directions in company with Mr. Hill, reviewing his work 

 and making additional observations. The following section is 

 the result of these labors, and I am so well convinced of the 

 accuracy of its essential features that I do not hesitate to adopt 

 it as the basis of my paleontological and museum work in relation 

 to the Texas Cretaceous, although the order of superposition 

 therein given is so different from what it has been generally sup- 

 posed to be. 



The remarks at the right hand side of the column, which repre- 

 sents the section, are by Mr Hill, who has with considerable 

 care compared this section with those which have hitherto been 

 published as representing the Texas Cretaceous. 



