312 EePORT OF THE DEPARTMENT OF ENTOMOLOGY OF THE 



the fruit. Collections were made of the various insects upon the 

 trees and the surrounding weeds and a large number of hemipterous 

 species were obtained, among which Lygus pratensis L. was most 

 abundant. Individuals of this latter species were then confined 

 separately about pears to determine if they were responsible for the 

 injuries. While some of them punctured the fruit, none of the 

 resulting wounds seemed to be quite* like the injury to pears so 

 apparent in the orchards, and the conclusion drawn from the tests 

 was that the destructive agent was some other species of insect. 

 In the spring of 1909 a careful watch was maintained on a number 

 of orchards that had been severely attacked during the preceding 

 year, and on June 12 the flowing of sap from young fruits was observed 

 by the authors in company with Mr. B. D. Van Buren of the State 

 Bureau of Horticulture. A closer examination of the pears showed 

 that a good many green hemipterous nymphs were present among the 

 fruit clusters and were feeding upon the tender pears. Many of these 

 nymphs were collected, brought to the grounds of the Experiment 

 Station and confined separately to young pears, which they immedi- 

 ately attacked. Those injured by the nymphs later became covered 

 with hard, granulated spots which were indistinguishable from much 

 of the damaged fruit which existed in orchards known to be infested 

 with the insect. From the nymphs, adults were obtained which 

 were forwarded to Mr. E. P. Van Duzee for identification, who 

 determined the species as Lygus invitus Say. The foregoing obser- 

 vations and tests have been repeated in succeeding years, always 

 with the same results, so that the identity of the culprit and the 

 nature of its activities, in view of the previous somewhat uncertain 

 knowledge of the insect, may now safely be said to have been firmly 

 established. 



FOOD PLANTS. 



As has already been indicated, pears suffer most from the work of 

 this insect, and judging from conditions in New York this fruit 

 appears to be its favorite cultivated host-plant. Uhler 8 mentions 

 the occurrence of the insect on wild grape blossom clusters in Mary- 

 land, and young nymphs of this same species have been observed in 

 considerable numbers among grape blossoms of native varieties 

 growing about Geneva. This insect has also been occasionally 



*Proc. Bost. Soc. Nat. Hist. 19:407. 1878. 



