1903.] Gidley, Fresh-water Tertiary of Northwestern Texas. 629 



observations and in his interpretation of the strata in this 

 locality. The writer could find no warrant for making any 

 separation of the beds at Mulberry Canon, either on strati- 

 graphic or palseontologic grounds. 



Briefly, Cummins's stratigraphic grounds for separating the 

 Goodnight beds from the Loup Fork division are as follows: 

 ( I ) That the Loup Fork beds in the vicinity of Clarendon were 

 overlaid by the heavy cross-bedded conglomerate layer which 

 underlies the upper series of strata at Mulberry Canon. (2) 

 That there is a marked difference in his two sections taken on 

 opposite sides of Mulberry Canon. He says of these sections : 

 "It will be apparent upon examination of these two sections 

 that there is a marked difference between them. The heavy 

 bed of conglomerate on the north side of the canyon, No. 4 of 

 the section, does not occur on the south side, nor was there 

 any gravel on that side to show that the conglomerate bed had 

 ever been there." 



This statement is incorrect, for the writer found an abun- 

 dance of gravel on both sides of the canon and had no trouble 

 in tracing the conglomerate layer (No. 4 of Cummins's section) 

 across to the south side of the canon where it is exposed in two 

 localities, showing a maximum thickness of at least fifteen feet. 

 This bed of conglomerate and sand is nowhere of great width, 

 hence it does not appear in every section on either side of the 

 canon. The writer also found this coarse conglomerate bed 

 appearing again in the Clarendon locality, resting directly on 

 the eroded surface of the Triassic and underlaying the Miocene 

 beds, but not overlaying them, as reported by Cummins. There 

 are scattered patches of loose gravel partially covering the 

 Miocene deposits in the vicinity, but it is superficially distrib- 

 uted and nowhere can be said to be in its original bed of 

 deposition. It was probably this frequent occurrence of loose 

 gravel which led Cummins to believe that the conglomerate 

 bed had overlaid the Miocene in this locality. 



Cummins's two sections taken at Mulberry Canon are mis- 

 leading, for no two sections, even though taken on the same 

 side of the canon, agree in detail. There is, therefore, no such 

 real difference in the two sides of the canon as these sections 



