BCIENCE— ADVERTISEMENTS 



The University of California Press 



Berkeley' California 280 Uadison Avenue, NewTork 



IFUGAO XAW 



By R. F. Barton $2.00 



The Fermentation Organisms of California 



Grapes. By W. V. Cruess .' 75 



On the Existence of a Growth-Inhibiting Sub- 

 stance in the Chinese Lemon. By H. S. 

 Reed and F. F. Halma 25 



Notes on the Germination of Tobacco Seed. 

 By T. H. GooDSPEED. 10 



A Muscid Larva of tl^e San Francisco Bay Re- 

 gion Sucking the^piood of Nestling Birds. 

 By O. E. Plat'h. '. 10 



The Action of TJltraviolet Light on Certain Bac- 

 teria in Relatio.n; of Specific Absorption by 

 Amino Acids. By .E.. I. Harris and H. S. 

 HOYT ..:...... 10 



The above titles represent University of California 

 Publications in Agricultural Science, Botany, American 

 Archaeology and Ethnplogy, Pathology, and Zoology. 

 Other series published by the University of California 

 include: Entomology, Geography. Geology, Physiology, 

 and Psychology. 



Complete Lists of Titles and Prices will be sent 

 on Request 



Elementary Course in 



Differential Equations 



By EDWARD J. MAURUS 



Noire Dame University 



For students in the first and second 

 years of engineering courses in connec- 

 tion with or supplementing a course in 

 integral calculus. The language is clear 

 and direct, and the working of each case 

 is illustrated by a completeU' solved 

 problem. The problems to be solved 

 are abundant in number and range from 

 the fairly obvious to the very difficult. 

 The brevity and simplicity of the book 

 should make it very valuable in courses 

 crowded for time. 



51 pages, 72 cents 



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