REPORT OF THE ENTOMOLOGIST. AND BOTANIST 



191 



SESSIONAL PAPER No, 16 



tliat there were very few of the wingless forms, but a great number of the winged ones. 

 Up to this time very few leaves had fallen off, although the growth of the trees was 

 completely stopped; in fact, our trees have apparently made no growth at all this year, 

 excepting a few that were free from the Psylla. At the time of writing, August 27, 

 the wingless forms have again become numerous and the winged ones few.' — W. R. 

 Dewar. 



Mr. John Chute, of Berwick, N.S., also observed that those of his trees which 

 were infested by the Pear-tree Flea -louse made no growth. 



This insect was first noticed as injurious in Canada in 1894, and a short account 

 of it, with the best remedies for controlling it, appeared in my annual report for that 

 year. The attack may be described as follows : — Small clear-winged insects, wedge- 

 shaped lilve miniature cicadse, the head being broad, flat in front, and the body pointed 

 behind; one-tenth of an inch in length, of a reddish brown colour, with broad black 

 bands across the abdomen. These insects, at the slightest disturbance, leap from the 

 foliage of infested pear trees and fly for a short distance. With the above described 

 form, there will be found on the leaves the curious flattened oval larvae, which, when 

 first hatched, are extremely small, only one-eightieth of an inch in length, of a semi- 

 translucent yellow colour, with bright red eyes. These grow rapidly, and in about 

 a month pass through five nymph stages, during which the body retains its flattened 

 form and becomes mtich darker until, in the full-grown nymph, the large wing-pads 

 and the greater part of the upper surface are black. The eyes and sometimes the body 

 between the black markings are crimson. The presence of this insect upon trees is 

 easily detected by the copious secretion of honey-dew with which the leaves, limbs 

 and trunks of the trees soon become covered, and upon which the dirty looking Sooty 

 Fungus "(Fumcigo salicina) develops. After a time the leaves and young fruit fall off 

 end the trees assume an unhealthy, gnarled appearance. Hardly any new growth is 

 made, and in cases of severe attack, trees die. 



The life-history of this insect has been carefully worked out by Prof. Slinger- 

 land, of Cornell University, and has been fully described in Cornell Bulletin No. 108, 

 published in 1898, as well as in U. S. Div. of Ent., Circular No. 7, 2nd series, by Mr. 

 C. L. Marlatt. 



The remedies for this insect are the spraying of the trunlis of trees which are 

 known to have been infested, during the winter or early spring, with kerosene emulsion, 

 whale-oil soap solution, or whitewash. This is to destroy the hibernating adults, 

 which pass the winter hidden away beneath flakes of bark or in crevices. 



The eggs are laid very early in spring long before the leaf buds expand. After leav- 

 ing their winter quarters and after the sexes have mated, the females lay their curious 

 pear-shaped and tailed eggs (fig. 19) near the tips of the young wood. The young flea- 

 lice hatch from these about the middle of May 

 or sooner, and immediately begin sucking the 

 sap from such leaves as have unfolded. Mr. 

 Joseph Tweddle, of Fruitland, Ont., tells me that 

 he obtained very satisfactory results in destroy- 

 ing the Pear-tree Psylla in orchards which he had 

 spmyed with the lime and sulphur wash to con- 

 trol the San Jose Scale. He was under the im.-' 

 pression that the mixture destroyed the e^g upon 

 the young wood, which is highly probable. It 

 frequently happens that fruit growers do not 

 know of the presence of this enemy in their or- 

 chards until they notice tlieir pear trees becoming 

 dirty and black during June, or a little later in 

 the year notice that the leaves are falling. As 

 soon as the insect is noticed in sulficient numbers to cause injury to the trees, these 



6 



Fig. 19. — Pear-tree Flea-louse: a, egg; 

 b, larva— both greatly enlarged. 

 (Marlatt, U.S. Dept. of Agriculture.) 



