Geology and Mineralogy. 67 



No. 186. — Stream Pollution by Acid-Iron Wastes. A Report 

 based on Investigations made at Shelby, Ohio ; by Herman 

 Stabler. Pp. 36, with 1 plate. 



2. The Origin and Structure of the Roxbury Conglomerate; 

 by George Rogers Mansfield. Pp. ] 80, 1 pis. Cambridge, 

 Mass., Nov. 1906. Bull, of the Museum of Comparative Zoology 

 at Harvard College, vol. xlix. Geol. Series, vol. viii, No. 4. — 

 The term Roxbury Conglomerate is applied to a series of ancient 

 sediments which occupy a large part of the so-called Boston 

 Basin. The series consists of arkoses and coarse and fine con- 

 glomerates, interbedded with sandstones and shales, and is 

 considered to be the equivalent of the massive Carboniferous 

 conglomerates of the Narragansett Basin. 



The author has made a thorough study of the formation as a 

 whole, but to geologists in general the most valuable portion of 

 the report consists in the discussion, covering forty-five pages, on 

 the origin of conglomerates. A careful search of the literature 

 has been made and the observations and opinions of various 

 writers assembled and well discussed. The careful reader will 

 notice, however, that there is a great scarcity of real observa- 

 tion and too much hypothesis in many of the statements quoted, 

 causing generalizations to be founded upon few examples and 

 sometimes upon mere opinions. 



In the general summary eleven conclusions are stated of which 

 perhaps the two most significant are : (S) The evidence, largely 

 negative and unsatisfactory, favors non-marine origin for this 

 Carboniferous formation ; (9) Glaciers were not directly con- 

 cerned with the deposition of the conglomerates, but they prob- 

 ably furnished material to torrents by which it was deposited 

 either upon the land or in lakes. j. b. 



3. Geology of the Bighorn Mountains / by N. H. Darton. 

 IT. S. Geological Survey. . Professional Paper No. 51. Pp. 129, 

 pis. 47, figs. 14, 1906. Washington. — This paper, accompanied 

 by a geological map, is a readable and valuable report of a region 

 interesting alike to the tourist and to the scientist. The geologi- 

 cal structure is well exposed, the marks of previous glacial action 

 are strongly developed and the scenery is of a high order. The 

 illustrations, reproduced from photographs, taken by several 

 geologists, are of high artistic merit and add greatly to the 

 attractiveness and value of the report. The treatment of the 

 sedimentary formations is especially complete. j. b. 



4. The Glacial History of Nantucket and Cape Cod, with an 

 argument for a fourth center of glacial dispersion in North 

 America ; by J. Howard Wilson. Pp. 90, pis. and folding- 

 maps xxxviii, 1906. New York (The Columbia University 

 Press. The Macmillan Co. agents). — Mr. Wilson has made a 

 very complete study of the glacial phenomena of Cape Cod and 

 the islands to the south, representing the most southeasterly 

 exposure upon the continent of the terminal moraine. Evidence 

 is found for the unsuspected conclusion that Newfoundland and 

 Nova Scotia formed a separate center of glacial dispersion of 



