448 Recent Literature. [oct. 



spores of this serious tree pest. A third paper ^ on this general subject 

 has also been published, and it establishes the fact that insects are im- 

 portant carriers of the blight. " In proportion to size " say the authors, 

 " insects may carry a greater number of spores of the blight fungus than 

 birds. We are led to the conclusion that some in.sects .... are im- 

 portant agents in the local dissemination of this disease." 



These findings make it certain that no large part of the responsibility for 

 spreading chestnut blight can be placed upon birds, for it is evident that 

 bird vectors are far from indispensable to a pest that has at its service, 

 innumerable insects, and the ubiquitous wind. — W. L. M. 



Economic Ornithology in Recent Entomological Publications. — 



The army worm {Cirphis unipiuicta) is one of those pests of agriculture 

 which appear in large numbers, now here, now there, but which in spite 

 of the sporadic nature of their outbreaks wreak the most serious damage. 

 Never has an infestation of army worms been studied without yielding 

 evidence of the importance of bird enemies of the pest. Mr. H. H. Knight, 

 of Cornell University, who investigated the army worm during the 1914 

 outbreak in New York, gives the following commendation ^ of the birds : 

 " Certain species of birds were very numerous in fields infested with army- 

 worms. One large hay field, situated on low ground and in the proximity 

 of timber, was frequented daily by a large flock of crows. The crows 

 destroyed the worms so fast that the field never became brown as was the 

 case in all other infested meadows. Flocks of cowbirds and grackles were 

 doing good work in some fields. The meadow lark and the robin were also 

 observed eating the larvae." 



In a Farmers' Bulletin ^ giving a general discussion of the army worm, 

 Mr. W. R. Walton, remarks that: " Most fortunately for the farmer, the 

 army worm has many natural enemies among the native insects, reptiles, 



birds, and mammals According to the records of the United States 



Biological Survey, more than 40 species of native wild birds are known to 

 eat the army worm in its various stages. Among the most important of 

 these are the following : Crow Blackbird or Grackle, Yellow-headed Black- 

 bird, Chipping Sparrow, Bluebird, Prairie Hen, and European Starling. 

 Domestic Fowls of all kinds will greedily devour the caterpillars and pup^e 

 if allowed to roam over infested fields. Skunks and toads also undoubtedly 

 eat thousands of the army worms, both caterpillars and pupse. These 

 birds and other animals should therefore be encouraged and protected by 

 the. farmer by all possible means." 



Damage by the clover leaf-hopper, due to the small size of the pest 

 which is overlooked, is usually attributed to soil or climatic deficiencies. 

 It is really considerable, however, and it is fortunate that natural enemies 



■ The army-worm in New York in 1914, Bull. 376, Cornell Univ. Agr. Exp. Sta., May, 

 1916, p. 763. 

 2 No. 731, U. S. Dept. Agr., May 23, 1916, pp. 9-10. 



