REVIEWS 87 



expect satisfactory results if they are not so performed. If there be 

 any criticism to be made of this portion of the work it is to wish that 

 more mention had been made of possible interfering elements, for the 

 field mineralogist rarely has cabinet specimens to deal with. 



In the next chapter the blowpipe and chemical reactions are tabu- 

 lated in a form which will be recognized as a distinct improvement on 

 those of the earlier book. The tables are models of clearness and com- 

 pleteness. With an introduction to the use of the tables, the revised 

 portion of the work closes, but promise is made of an early revision of 

 the tables, including the introduction of new species and many changes 

 and corrections in the chemical formulje. To express the hope, which 

 will be general, that this promise may soon be fulfilled, is to bestow 

 the highest praise on the work which has been already done. 



O. C. Farrington. 



TJie Dinosaurs of North America. By Othniel Charles Marsh. 

 Sixteenth Annual Report of the United States Geological 

 Survey, Part I, p]>. 133-414. 



Under this title Professor Marsh has published, in an article of loi 

 pages of text, a resume of his long series of papers on the Dinosauria 

 of North America. Intended as it is for the general reader, there are 

 few new facts brought out, and the specialist finds little of value to 

 himself beyond the convenience of a condensed statement of Professor 

 Marsh's views, and the large collection of illustrations which form so 

 important a part of the paper. There are eighty-four plates and sixtv- 

 six figures in the text. Most of the plates are familiar to the readers of 

 the American Journal of Science, as they are enlarged copies of the 

 ones accompanying the author's papers in that journal. 



The author's aim is " to give the general reader a clear idea of some 

 of the type specimens of one great group of extinct animals that were 

 long the dominant forms of life in this continent." Of especial interest 

 to such a class must be the restorations attempted by Professor Marsh, and 

 it is well to issue a warning against receiving as entirely accurate 

 restorations which, made in many cases from incomplete material, can 

 only represent the author's idea of the most probable form of the 

 skeleton. In the same spirit of warning we must call attention to the 

 statement that "the best authorities regard them (the Dinosauria) as 

 constituting a distinct subclass of Reptilia;" indeed, it should be 



