324 JOURNAL OP ECONOMIC ENTOMOLOGY [A'Ol. 3 



followed by dear hot days and no rain, while spraying followed by cool days 

 and rains resulted in no injury. The suggested explanation is tluxt in the 

 former ease the dews at night would be suttioient to moisten the material and 

 the hot sun the next day would produce conditions needed to dissolve the 

 greatest amounts of arsenic, while if rain were to follow, the sodium chlorid 

 and carbonate would be washed out, leaving nothing to cause the breaking up 

 of the lead arsenate. 



The bulletin is a valuable one and very suggestive for those accustomed 

 to looking at such subjects from their chemical aspects. It is somewhat 

 questionable, however, if the average fruit grower might not desire a more 

 dii'ect series of statements as to the conclusions reached, which would guide 

 him better in his subsequent spraying. jj. T. F. 



Ants, their structure, development and behavior, by Willlvm 

 Morton Wheeler, Ph.D., Professor of Economic Entomology, Har- 

 vard University; Honorary Curator of Social Insects, American 

 Museum of Natural History. New York, Columbia University Press, 

 1910, p. I to XXV; 1-663; 286 figures. 



This is a comprehensive work written by an acknowledged master in the 

 group and dealing with the structure and biology of these extremely inter- 

 esting forms. The reader needs only to refer to the 70 closely printed pages 

 of the bibliography to gain some idea of tlie vast amount of labor in digest- 

 ing these almost innumerable and widely scattered records and co-ordinating 

 them with observations extending, over a decade. 



The author considers that the social relations, attaining their "richest 

 and boldest expression in the ants," arouses interc-st, owing to there being 

 an undeniable resemblance to human conditions. The character of this 

 volume is well indicated by chapters devoted to ants as donunant insects, 

 the external and internal structure of ants, development, polymorphism, 

 history of myrmecology and classification of ants, their distribution, fossil 

 ants, habits in general, ant nests, driver and legionary ants, harvesting 

 ants, relation of ants to vascular plants, fungus growing ants, honey ants, 

 guests, ecto and entoparasites, slave makers, the instinctive and plastic l>e- 

 havior of ants. 



Economic entomologists will be particularly interested in the chapter 

 treating of the relation of ants to plantlice, scale insects, tree hoppers 

 and caterpillars. The discussion, while conq)rehensive, is not unduly extended. 

 Here, among other interesting notes, we find a very lucid account of the 

 aphid cornicles and their functions. The extermination of noxious species 

 is concisely discussed in an appendix. The value of this inqiortant work 

 is greatly increased by a key to the subfauiily, genera and subgenera of 

 the North American Formicidae, together with a list of the describetl vspecies. 

 The author is to be congratulated upon having produced an authentic, 

 scholarly discussion of a highly interesting group. 



Corn Weevils and Other Grain Insects, by R. I. Smith, N. C. 

 Agric. Exp't. Sta. Bui. 203, p. 1-27, 1908. 



This popular bulletin discusses in a summarized manner the more im- 

 portant grain insects. The author wisely emphasizes the value of preventive 



