76 Scientific Intelligence. 



This volume is the result of an attempt to represent all rocks by 

 means of formulas. Just as in chemistry two kinds of formulas 

 are necessary to represent adequately a chemical compound, so in 

 petrography two kinds are required in order to characterize a 

 rock complete^ : a molecular formula, which is based upon the 

 chemical analysis, and a constitutional formula, which gives the 

 texture, of the rock and the nature of the constituent minerals. 

 A new method of plotting chemical analyses of rocks is developed 

 and is believed to be superior to Osann's method. 



The underlying theoretical concept of the book is that all rocks 

 are derived from a single primary magma by fractional crystal- 

 lization (the crystallization- differentiation of Bowen). From 

 this genetic concept is developed a natural classification of rocks, 

 including the metamorphic and sedimentary groups, but this 

 classification, however, leaves the impression that it is but lightly 

 tied to the actual facts of the field. In volume two this system 

 is to be more fully elucidated. a. k. 



3. Geological Survey of Western Australia; A. Gibb Mait- 

 land, Government Geologist. — The Annual Progress Report for 

 1918 is notable for giving a large geological sketch map of 

 Western Australia (33 X 21 inches). This is on a scale of 50 

 miles to one inch, which is so liberal as to make a large amount 

 of detail possible. The report also contains a series of papers, 

 many of them economic in nature, dealing with deposits of 

 graphite, manganese, asbestos, molybdenite, bauxite, etc. The 

 occurrence of some rare minerals is also noted, as, gearksutite in 

 chalky nodules, jarosite in a fine yellow powder impregnating 

 sandstone, scheelite, gahnite and others. 



Bulletin No. 77, by Edward S. Simpson, discusses the sources 

 of industrial potash in "Western Australia. An appendix 

 describes the obtaining of potash and iodine from local seaweeds, 

 this is by I. H. Boas. Another describes, by T. Blatchford, 

 alunite deposits of Kanowna. 



Bulletin No. 82 is devoted to the magnesite deposits of Bulong 

 in the Northeast Coolgardie Goldfield. 



4. New Zealand Geological Survey; P. G. Morgan, Director. 

 — Bulletin No. 22 (new series) of the Geological Survey Branch 

 of the Department of Mines, by P. G. Morgan and others, is a 

 quarto publication of 316 pages, with 14 plates, 2 maps and 6 

 text-figures. The bulletin is devoted to the Limestone and 

 Phosphate Resources of New Zealand especially in relation to 

 agriculture. Part I, now in hand, discusses the limestone and 

 gives a full summary of the many deposits in the Dominion. 

 Occurrences in 72 counties of the North Island and 53 counties 

 in the South Island are noted. 



5. Principles of Animal Biology ; by A. Franklin Shull, 

 with the collaboration of George R. Larue and Alexander G. 

 Ruthven. Pp. xv, 441, with 245 text-figures. New York, 1920 

 (MacGraw-Hill Book Company). 



