206 REVIEWS 



Plata sandstone overlapped earlier sediments and came into contact 

 with the pre-Cambrian rocks along a general north-and-south line, 

 crossing the San Juan Mountains area." The pre-Dakota section of 

 Piedra Valley is given. 



A Reconnaissance in the Canyon Range, West-Central Utah. By 

 G. F. Loughlin. Professional Paper, U.S. Geo!. Survey, 

 No. 90-F, 1914. "Contributions to General Geology, 1914." 

 Pp. 51-66, pi. 1, figs. 4-8 (including map). 

 The Canyon Range in west-central Utah is formed almost wholly 

 of lower Mississippian and older( ?) limestone, and upper Mississippian 

 and Pennsylvanian( ?) quartzite, overlain unconformably by Eocene 

 conglomerate. Pleistocene Lake Bonneville beds and, locally, later 

 Quaternary deposits floor the valleys on either side of the range. "Vol- 

 canic rocks have been reported from the extreme northern and south- 

 western parts of the range, beyond the limits of the area visited." 



V. O. T. 



The History of a Portion of Yampa River, Colorado, and Its Possible 

 Bearing on That of Green River. By E. T. Hancock. Pro- 

 fessional Paper, U.S. Geol. Survey, No. 90-K, 1915. "Shorter 

 Contributions to General Geology, 1914." Pp. 183-89, pis. 2. 

 Yampa River, which is one of the principal tributaries of Green River 

 and empties into it from the east, is believed to be a superimposed stream 

 whose present course was established after the deposition and emergence 

 of the Browns Park formation (Eocene ?). It is thought that " the asser- 

 tions of the antecedent origin of Green River should be accepted only 

 after more facts have been obtained bearing on the original extent and 

 thickness of the late Tertiary formations, as well as on the diastrophic 

 history of the Uinta Range." v n T 



"The Gold-Bearing Gravels of Beauce Co., Quebec." By J. B. 

 Tyrrell. Bull. Am. Inst. Mining Eng., 1915, pp. 1-12. 

 Describes the placer deposits of the Chaudiere, Gilbert, and Des 

 Plantes rivers. A point of physiographic interest is the suggestion of 

 an Appalachian center of glaciation, from which the ice is thought to 

 have moved northwestward over the area included in the report. 



A. D. B. 



