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generally in the Kew England StatevS. Its sudden appear.auce in such 

 enormous numbers so far south was therefore a matter of considerable 

 surprise, and at the instance of Mr. Howard, I visited the orchard 

 twice, made careful examinations of the work of the insect, and con- 

 ducted some experiments with remedies. 



The pear-tree Psylla is by no means a common insect, and most ento- 

 mologists are unfamiliar with the interesting conditions accompanying 

 an excessive invasion of the pest. As described by Mr. Slingerland in 

 the case of the New York invasions of 1891 and 1892, and as witnessed 

 by myself at Capt. Emory's place, the indications of the presence of 

 the insect in its effects upon the trees are in the falling of the leaves 

 and fruit, the latter before it is half grown, but chiefly in the enormous 

 secretion of honeydew by the larvse and nymphs. One who has not 

 witnessed this sight gives credence with difficulty to the reports as to 

 the amounts of this liquid constantly being secreted. In the present 

 case the water-like fluid or honeydew not only covered the leaves and 

 twigs, but, to quote from an interesting account in the Chestertown 

 Transcript, " fairly rained fro)n the trees, and ran down the trunks to 

 the ground; and even now a discolored circle, extending for from 6 to 

 8 inches around the trees, attests the extent of the presence of this 

 liquid. Heavy and protracted rains kept the honeydew washed from 

 the trees for several weeks, so that it was not at first noticed, but after 

 the rainy season, when the trees were being worked, the horses used 

 became so drenched with the sticky substance that it became necessary 

 to wash it off with sponges, the currycomb being useless. The trees 

 became weakened and lost much of their fruit, the leaves became black- 

 ened and fell in great numbers, and the bodies of the trees look to-day 

 as if they had been smoked. The scene presented was certainly one 

 never before witnessed in Kent County. Twenty thousand beautiful 

 trees, many of them nearly stripped of their foliage, the remaining 

 leaves blackened and the trunks blackened by the honeydew, is a sight 

 well calculated to strike consternation and despair to the heart of the 

 average fruit-grower." 



When I visited the orchard on July 20 the transformation from the 

 last njanphal stage to the adult had taken place and the trees were 

 covered with adult insects only, and these had only just begun depos- 

 iting eggs for what was i)robably the second summer brood. The secre- 

 tion of honeydew had of course ceased, the excretion of the adults 

 being wax like and crystalliue,bntthe trees still bore marked evidences 

 of the secretion of a few weeks earlier. The leaves, limbs, and trunks 

 were blackened by the growth in the sweetish liquid of the smoky 

 fungus, Fnmago salicina, and in the falling of the foliage and the dis- 

 eased and smoky-looking fruit a picture of disaster was presented 

 which was rather startling in its effects. Mr. Slingerland has described 

 the appearance of the leaves of a tree severely attacked by this insect 

 as small, yellow, and easily falling. In Mr. Emory's orchard the leaves 



