April, '08] JOURNAL OF ECONOMIC ENTOMOLOGY 89 



The food plants which carry the species through its summer gen- 

 eration appear to be of great variety, as shown by the list already men- 

 tioned. So few lice are to be found, however, upon these plants dur- 

 ing the summer in comparison with the countless numbers which are 

 produced in the peach orchards in the spring that it seems very prob- 

 able that other plants will also be found harboring it through the 

 summer months. 



In the Grand Valley peach orchards the first returning migrants 

 were noticed about the middle of September, when I found them col- 

 lecting upon the dorsal side of the leaves, principally along the mid- 

 rib and veins, though they were not altogether restricted to these 

 points. No early examinations of peach orchards were made in Mis- 

 souri this fall, but on October 24, oviparous females were found de- 

 positing their eggs along the Mississippi and under date of November 

 5 Professor Gillette wrote me from Colorado that the eggs were be- 

 ing deposited upon peach, plum and cherry, though many of the 

 winged and wingless viviparous females were still living upon many 

 outdoor plants that had not entirely lost their foliage. The male 

 insects are winged and appear in Colorado from about the middle of 

 September to when they are killed by the cold nights. In Missouri, 

 near St. Louis many eggs were still being freshly deposited in peach 

 orchards as late as November 16. 



Parasites and predaceous enemies rendered the orchardists of west- 

 ern Colorado much service in destroying great numbers of these in- 

 sects last summer. Among these were the larvae of syrphus flies and 

 lace-wings, and the larvae and adults of lady beetles. A small hymen- 

 opterous parasite was seen to infest the lice and a Thomisid spider 

 identified by Mr. Banks as Thisumena lepida Thorell was observed to 

 be of service. Sparrows, canaries, orioles and other birds were also 

 of economic value. 



Experiments by the writer towards the control of this pest were un- 

 dertaken against it only so far as it affected the peach. In the com- 

 mercial orchards of Western Colorado its only injury has been caused 

 to this fruit. 



The remarkable power peach trees have of reviving after being 

 almost completely defoliated by these lice makes the insect somewhat 

 less formidable. However trees so completely stripped of their foliage 

 and devitalized as they are in some cases are retarded in both the de- 

 velopment of the tree and fruit. From a practical standpoint the de- 

 struction of the lice which may infest the fruit buds, blossoms or newly 

 formed peaches may be considered of the greatest consequence to 

 the grower. 



