456 Report of the Department of Entomology of the 



and from their injurious work upon various cultivated crops. They 

 are also suspected of acting as carriers of various plant diseases. 

 Many writers upon these insects have commented upon their carni- 

 vorous tendencies, and from this standpoint alone some have con- 

 cluded that the tree crickets are beneficial rather than inimical 

 to the farmer. The fondness of various species of these insects 

 for plant lice is well known, and when these occur in abundant 

 numbers they constitute an important item in the diet of the crickets. 

 Bruner 4 has noted the predaceous habits of latipennis and states 

 that it feeds on saw-flies, leaf-hoppers and tingitids. Conspicuous 

 constituents in the food of tree-inhabiting species, as niveus and 

 angustipennis, are scale insects. An examination of the crop contents 

 of a number of specimens of niveus from an apple orchard infested 

 with the San Jose scale has revealed the presence of varying numbers 

 of pygidia of this coccid which were intermingled with numerous 

 fragments of plant tissues and bristles, pieces of chitin, etc., of larger 

 insects. Unquestionably many other kinds of insects aside from 

 those mentioned fall as prey to these crickets. The actual importance 

 of tree crickets in this role deserves more careful consideration, 

 but on the basis of our studies it appears that their beneficial 

 services have, in the main, been over-rated because of their relatively 

 small numbers in comparison with other groups of predaceous and 

 parasitic insects. 



Their status as depredators on cultivated plants is more clearly 

 understood. One of the most injurious species is nigricornis, which 

 may seriously damage raspberry plantations, and it is widely dis- 

 tributed. The injuries are due primarily to the slitting of the canes 

 as a result of extensive oviposition, which weakens a stalk so that 

 it dies or breaks at the point of the wounded area from the weight 

 of the foliage or as a result of a strong wind. Certain species have 

 attained some distinction because of their depredations on various 

 fruits. Garman 5 has observed niveus and angusti'pennis feeding on 

 ripening plums and peaches, and latipennis on grape clusters. The 

 attacks of the latter species were considered especially injurious, as 

 the rupturing of the epidermis of the fruits apparently facilitated 

 the spread of black rot. Wounds in the other fruits also became 

 centers of infection with brown rot. Saunders 6 of Canada has 



4 L. Bruner, Nebr. Exp. Sta. Bui. 14. 1890. 



s H. Gal-man, Ky. Agr. Exp. Sta., Bui. 116. 



6 W. Saunders, Ont. Ent. Soc, Rept. for 1873. 1874. 



