326 Forty- SIXTH Report on the State Museum 



Some of these injuries have ah-eady been referred to, as in the 

 orchards of Mr. Powell, in Ghent, IST. Y. The extensive pear orchards 

 of Coe Brothers, at Meriden, Conn., have for several years suffered 

 severely from it. In a letter from Mr. A. J. Coe, dated September 7th, 

 1891, he wrote that on his return from Europe, a few weeks previous 

 to his writing, he found that his pear orchard had been devastated by 

 the Psylla, and bore very little fruit. 



A severe attack prevailed in a pear orchard of Mr. H. S. Wright, 

 of Ithaca, N. Y., during the season of 1891. Mr. Slingerland, who 

 saw the orchard in November of that year, has reported of it as fol- 

 lows: " The whole orchard appeared as though a tire had swept quickly 

 through it, scorching the trees and blackening the trunks, large 

 branches and the smallest twigs. Both young and old trees of dwarf 

 and standard vaiieties had been attacked. Most of the trees had made 

 little or no new growth during the season, and many buds were then 

 dead." 



Dr. LeBaron has described severe injuries from it in the State of 

 Illinois, in the year 1871, when young pear trees had been so badly 

 attacked by it that '^ the leakage of sap from the axils of the leaves 

 [? the honey-dew given out by the insects] had in some instances run 

 down the branches and trunk to the ground." 



The frequent death of pear trees in former years, from unknown 

 causes, after a season of languishing, is now believed to have been 

 owing to the unsuspected presence of this insect, which from its minute 

 size may have easily been overlooked. Mr. Powell unhesitatingly 

 charges the recent death of many of his trees to Psylla attack. Certain 

 it is, that a continuance for several years in succession of such injuries 

 as have been cited, must necessarily prove fatal to the trees. If not 

 carried to this extent, — in years of abundance of the Psylla, the crop 

 would be a failure. The leaves, covered with a thick coating of the 

 honey-dew and the sap withdrawn from their foot-stalks, would cease 

 in midsummer to perform their functions and would fall to the ground: 

 without them, the fruit could not mature. 



Life-history. 

 There was not the opportunity during the season of 1891 to make 

 a study of the life-history of this insect, or to learn much more of it 

 than what has been given in the preceding pages. The following year, 

 its abundance at Ithaca gave to Mr. Slingerland the oj)portunity 

 of watching its development and habits; and in a Bulletin (No. 44) 

 issued by the Cornell University Agricultural Experiment Station, 

 under date of October, 1892, he has given to the public its entire life- 

 history carefully worked out, together with its early history, descrip- 



