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The astonishing total of 3,383 pages is shown by the works men- 

 tioned. Probably no group of insects has so quickly sprung from 

 comparative obscurity as has this family. The gi-eat importance of 

 their control in the lessening and prevention of diseases and in add- 

 ing to the comfort of our citizens warrants the belief that these 

 insects must receive considerable attention at the hands of economic 

 entomologists in the future. 



Along with the work on the San Jose scale, the boll Aveevil, and 

 mosquitoes, much other important and good worlc has been accom- 

 plished. On a closer examination many of our old-time pests are 

 still disclosing new facts. Native or introduced species, previously 

 of but little importance, have, under favorable conditions, become so 

 numerous and injurious that their prompt and tliorough study has 

 become necessary. The efficiency of insecticides and remedial prac- 

 tices has been constantly improved. Recent experiments with arse- 

 nate of lead for the codling moth give promi>;e of a still greater re- 

 duction of the percentage of wormy fruit. The evolution of our 

 knowledge concerning the life and manners of almost any insect 

 species and the development of measures for its control would furnish 

 an interesting chapter in the liistory of economic entomology in this 

 country, and the gradual accumulation of facts and improvements in 

 remedial measures may properly l)e compared to the evolution of a 

 harvester or sewing machine. Looking back over the subject, points 

 in life history Avhich at the time of their discovery appeared trivial 

 enough, are seen, in the light of the completed record, to have been 

 the key to the situation. The determination of all points connected 

 with the life and habits of an injurious species is not only warranted 

 for scientific reasons, but we are only able to judge of the importance 

 of any point after all the facts concerning it have been completely 

 rounded up. 



The growing efficiency of our battery for insect warfare and the 

 increasing familiarity of growers of crops with its use must result 

 in the important lessening of insi^ct injuries. With mimerous spe- 

 cies, as the Colorado potato beetle, cankerworms, cabbage worms, 

 and other species feeding on exposed portions of plants, the arsen- 

 ites are practically specifics, and the question of preventing losses 

 resolves itself largely into inducing the utilization of these remedies. 

 The successful control of other species is frequently more complicated 

 and requires the exercise of considerable judgment. Thus spraying 

 for the codling moth must be done with reference to the stage of 

 development of the young fruit. The sowing of fall wheat, to avoid 

 injury from the Hessian fly, must be timed with nicety. Poisoning 

 cotton for the cotton boll Avorm must be done with reference to the 

 condition of adjacent corn. 



It has perhaps been a standing excuse with us, in accounting for the 



