Geology and Mineralogy. 145 



of the geologic work are briefly but comprehensively described.* 

 The condition and progress of the topographic work are illustrated 

 by a general map. 



A Geological Reconnoissance across Idaho y by George H. 

 Eldridge, pt. II, pp. 66, 3 pi., 4 figs. Between Salmon City and 

 Boise ten formations besides a great variety of eruptive rocks 

 are noted. The granites and syenites, in part at least, are prob- 

 ably Archaean ; the schists are Algonkian. Quartzites are dis- 

 tributed from the Algonkian to the Carboniferous, while the 

 limestones may include both Silurian and Carboniferous. The 

 age of the great calcareous shale series of the Wood River dis- 

 trict is undoubtedly Paleozoic and probably Carboniferous. The 

 sandstones and clays are all of Tertiary age and Post-Pliocene 

 gravels are abundant. In the Continental divide the structure is 

 anticlinal, trending northwest and southeast, but at some other 

 points, especially in the western part of the state, the structure 

 lines trend east-northeast. 



Mineral Resources of the United States ; by David T. Day, 

 pt. Ill, Metallic Products, 646 pp., 13 pi., 9 figs., and pt. IV, 

 Non-metallic Products, 735 pp., 6 pi. By an act of Congress the 

 reports on mineral resources, which were heretofore published in 

 separate volumes, are now included in the annual report of the 

 director but the parts are bound separately. Most of the 3*7 

 articles contained in these parts are of a statistical nature, but 

 some of them, as for example Reconnoissance of the Gold Fields 

 of the Southern Appalachians by G. F. Becker (see this Journal 

 for Jan. 1896, p. 57), and Bauxite by C. W. Hayes, pt. Ill, p. 

 £47, contain valuable contributions to economic geology.f 



A Mineralogical Lexicon of Franklin, Hampshire and Hamp- 

 den Counties, Massachusetts ; by B. K. Emerson. Bulletin No. 

 126, 8vo, 180 pp., 1 pi., 5 figs. This bulletin gives a condensed 

 history of each mineral species occurring within the area indi- 

 cated and is conveniently arranged for reference. 



The Bear River Formation and its characteristic Fauna; by 

 C. A. White. Bulletin No. 128, 8vo, 108 pp., 11 pis. Its fauna, 

 which is non-marine, consisting of 48 species, is fully illustrated 

 and described. The position of the formation is designated as at 

 or near the base of the Upper Cretaceous series, thus correcting 

 earlier opinions and confirming the author's suggestion as well as 

 the investigations of T. W. Stanton, who published an article 

 upon the same subject in this Journal, III, vol. xliii, pp. 98-115. 



Earthquakes in California in 1894- ; by C. D. Perrine. Bul- 

 letin No. 129, 8vo, 23 pp. 



Report of Progress of the Division of Hydrography for the 

 calendar years 1893 and 1891^; by F. H. Newell. Bulletin 

 No. 131, 8vo, 126 pp. j. s. d. 



* See the preceding review. 



f Six papers in part I of the Sixteenth Annual Report and five in part II are 

 yet to appear and will be noticed when issued. Parts III and IV are now com- 

 plete. 



Am. Jour. Sci.— Fourth Series, Yol. I, No 2— February, 1896 

 10 



