Geology and Mineralogy. 521 



Supply of the United States, Part VIII, Western Gulf of Mexico 

 Basins. Pp. 725; 3 pis. 



Nos. 375, B, C, D, E. Contributions to the Hydrology of the 

 United States, 1915. Pp. 51-130. 



2. Relation of the Cretaceous Formations to the Rocky Moun- 

 tains in Colorado and New Mexico ; by Willis T. Lee. Prof. 

 Paper 95-C, U. S. Geol. Surv., 1915, pp. 27-58, pi. V, text figs. 

 12-22. — A carefully wrought out paper showing that the present 

 Rocky Mountains in Colorado, New Mexico, and Wyoming did 

 not exist as such in late Mesozoic time, and that these areas 

 were covered with many thousands of feet of Cretaceous strata. 

 There were no granitic island masses in the Cretaceous sea of 

 Colorado, as held by some geologists. These results have a direct 

 bearing on the problem of the Cretaceous-Tertiary boundary in 

 the Rocky Mountain region. The author says: "Certain con- 

 glomerates that rest unconformably on Cretaceous beds are 

 regarded as basal Tertiary by some geologists and as Cretaceous 

 by others. These conglomerates contain great numbers of peb- 

 bles of crystalline and metamorphic rocks such as are now found in 

 the mountains, and they are so distributed as to prove that they 

 were derived from the present mountainous areas. Inasmuch as 

 the Cretaceous formations were originally continuous over the site 

 of these mountains, it follows that there must have been uplift 

 and erosion sufficient to remove them and to reach the pre-Creta- 

 ceous rocks before the materials for the conglomerates could be 

 obtained. In the Rocky Mountain region of Colorado and New 

 Mexico all deposits above these conglomerates are of the nonma- 

 rine type that characterizes the undisputed Tertiary formations 

 of the same regions " (p. 57). He then concludes : " It naturally 

 follows that the conglomerates and other sediments derived by 

 erosion from the newly uplifted mountains — such as those of the 

 Denver, Arapahoe, Dawson, Raton, and related formations — 

 belong to the Tertiary system" (p. 58). c. s. 



3. Conceptions regarding the American Devonic ; by John 

 M. Clarke. N. Y. State Mus., Bull. 177, 1915, pp. 115-133, — 

 An excellent paper, written in Clarke's characteristic style and 

 prepared to commemorate the seventieth birthday of the Euro- 

 pean authority on the Devonian, Professor Emanuel Kayser. 

 It brings within a small compass much of our knowledge of the 

 American Devonian sequence and distribution, and its correlation 

 with the occurrences of the Devonian in the rest of the world. 



c. s. 



4. Fauna of the San Pablo Group of Middle California ; 

 by Bruce L. Clark. Univ. Calif. Pub., Bull. Dept. Geology, 

 vol. 8, No. 22, 1915, pp. 385-572, pis. 42-71.— This work brings 

 together all that is known of the Upper Miocene strata and fauna 

 of Middle California. There are 165 species, and of these 135 

 (72 new) are determinable molluscs ; 32 are living (21 per cent). 



c. s. 



5. The Cretaceous Sea in Alberta; by D. B. Dowling. 

 Trans. Royal Soc. Canada, ser. Ill, vol. ix, 1915, pp. 27-42, 



