1392.] Geology and Paleontology. 100 



interest to the general reader. The sources of the metal, the forms 

 and conditions of deposition and precipitation, and the geologic distri- 

 bution, are given in a clear, concise ami orderly way that shows a 

 mastery of the subject. 



The richest deposits in the I'nited States are confined almost 



found in the Lower Carboniferous. 



conditions surrounding the deposition. 



A geological map of the Batesville, Arkansas, region is folded in 

 the pocket of the volume, and the text is still further illustrated by a 



Geological Survey of Texas, 1890. — The Second Annual 



with information, valuable not only to the citizens of the state, but 

 also to the geologists at large. The report of the State and Field 

 Geologists are followed by an admirable series of papers which take 

 up in detail a study of each formation with it- various economic min- 

 erals and possibilities. Messrs. Dumhle. P.irkiubine, Lerche, Kennedy, 

 Herndon and Walker report on the Iron Ore District of East Texas; 

 Mr. Cummings gives the geology of the north-western part of the 

 State : Mr. Comstock the geology and mineral resources of the central 

 mineral region; and. finally, Mr. Stiver. .witz describes the geology 

 and mineral resources of Trans-Pecos, Texas. 



A separate chapter is given to a description, by Alpheiis Hyatt, of 

 the Carboniferous Cephalopods. These forms being extremely limited 

 in their chronological distribution are helpful in distinguishing the 

 age of the rocks in which they are found, and it was therefore decided 

 to have them all published in one treatise. 



The report is abundantly illustrated with plates, sections and maps, 

 which add materially to its value and interest. 



Geological News-General.— It is the opinion of Mr. Waldemar 

 Lindgren that there exists in southern Lower California two orogra- 

 phic lines of great importance. (1) A comparatively recent, probably 

 Post-cretacic line of dislocation extending from the vicinity of La Paz 

 northward for many hundred miles along the eastern coast. (2) A 



« Second Annual Report of the Geological Survey of Texas, 1890. E. T. Dumble> 

 State Geologist. 



