202 . REVIEWS 



species became extinct before the Midway group (lowermost Eocene) 

 was deposited. Stephenson quotes T. W. Vaughan as follows: "The 

 changes that took place in the marine animal life of the Atlantic and 

 Gulf Coastal Plain during the time represented by the unconformity 

 separating the Cretaceous and Eocene of this area are more striking than 

 the changes that have taken place between earliest Midway time and 



the present day " 



V. 0. T. 



The Stratigraphy of the Montana Group, with Special Reference to 

 the Position and Age of the Judith River Formation in North- 

 Central Montana. By C. F. Bowen. Professional Paper, 

 U.S. Geol. Survey, No. 90-I, 1915. "Shorter Contributions 

 to General Geology, 1914." Pp. 95-153, pi. i- 

 The area treated in this report "lies east of the Big Snowy and 

 Judith mountains and extends from Musselshell, on Musselshell River, 

 to Judith, on Missouri River, Mont." The generalized section of the 

 sedimentary rocks in ascending order is as follows : Cretaceous : Colorado 

 shale (thickness not measured), Montana group (Eagle sandstone) 

 (200-300 feet), Claggett formation (700 =•= feet), Judith River formation 

 (250-500 feet), Bearpaw shale (1,100=^ feet); and the Eocene(?) 

 Lance formation (700-800 feet). There is no evidence of an uncon- 

 formity at any horizon in this section. 



It is concluded that "the evidence of the vertebrate fauna, so far as 

 in the present state of knowledge it has any weight, and the evidence of 

 the fresh- and brackish-water invertebrates, so far as it is decisive for 

 accurate time determination, indicate a closer relationship between the 

 Belly River [of Canada] and Judith River than between either of these 

 formations and the Lance. This is in accord with the stratigraphic 

 evidence, which shows conclusively that both the Judith River and 

 Belly River formations are separated from the Lance by amarine 

 formation which is of undoubted Cretaceous age." 



V. 0. T. 



Statistics of the Mineral Production of Alabama for 1913. By 

 Charles A. Abele. Geol. Surv. of Alabama, Bull. 15. 

 University, 1914. Pp. 67. 

 A compilation from Mineral Resources of the United States. 



A. D. B. 



