SCIENCE—ADVERTISEMENTS 



A Synopsis of the 



Aphididac of California 



By ALBERT F. SWAIN 



221 pages. 17 plates. Paper, $2.25 



Other Recent Publications 



Calendars of the Indians north of Mexico, by I^eona 



Cope $ .75 



The Effect of Several Types of Irrigation Water on 

 the Ph Value and Freezing Point Depression of 

 Various Types of Soils, by D. R. Hoa^land and 

 A. W. Christie 20 



Notes on the Natural History of the Bushy-tailed Wood 



Rats of California, by Joseph Dixon 25 



Geology of a Part of the Santa Ynez River District, 



Santa Barbara County, Cal., by Wm. S. W. Kew .25 



The Marine Algae of the Pacific Coast of North Amer- 

 ica, Part I. Myxophyceae, by William A. Set- 

 chell and Nathaniel I.yon Gardner 1.50 



The University of California Press 



Berkeley, California 280 Madison Ave, New York 



A Fused Course 



McCLENON AND RUSK'S 



Introduction to the 

 Elementary Functions 



Unifies the various subjects in mathe- 

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 Advantages are : ( 1 ) it avoids duplication ; 



(2) it connects better with secondary- 

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(3) it gives an adequate idea of mathe- 

 matics in content and methods because 

 the idea of functionality is brought into 

 the central position; (4) it develops great 

 resourcefulness in the student. 



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Spencer non=Objective 

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Possess all the features of construction which experi- 

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 Among them is the one very distinctive feature which 

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Convergent Eyepiece Tubes 



which avoids the excessive and false conception of per- 

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I92O Catalog sent on request 



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