April, '08] JOURNAL OF ECONOMIC ENTOMOLOGY 87 



dividuals of all generations appearing after the spring stem-mother 

 remain greenish in color throughout the season up to when the sexual 

 females are found upon the leaves in the fall. These deposit the over- 

 wintering eggs and the lice are also of a salmon or pink shade, very- 

 much like the stem-mothers of the spring. 



I have counted as many as a score of the stem-mothers in the spring 

 clustered over the surface of a single unopen bud. When the buds 

 break into bloom, these stem-mothers and their progeny crowd within, 

 attacking petals and inner walls of the corolla as well as the stamens, 

 style and ovary. The bloom is distorted, becomes withered and finally 

 falls. In other cases the clusters of lice form later about the peaches, 

 when about the size of peas, and by sucking away the sap cause them 

 to also fall from the trees. About this time the lice will also begin to 

 infest the leaves, curling them tightly, by infesting their under sur- 

 faces, and when severely attacked all parts of the leaf -blade will be 

 completely covered. After the second molt of the stem-mothers, 

 minute drops of honey-dew may be seen to form at the tip of the 

 insects 's body and be thrown away with a quick movement. This 

 honey-dew may appear before the buds open as moist, sticky areas 

 upon the twig above the louse. Later in the spring, the leaves in 

 badly infested terminal clusters become completely coated with this 

 secretion and attract numbers of ants, flies and other insects. 



The infested leaves become thickened and pitted from beneath, turn- 

 ing red in spots and finally falling away. About the middle of May, 

 1907, many peach trees in "Western Colorado were almost completely 

 stripped of their foliage and it was feared by many growers that 

 some would never revive. 



Winged lice developed among individuals of the first generation 

 following the spring stem-mothers and were seen in the orchards as 

 early as April 13, 1907. They appeared as a rule first upon leaves 

 greatly over-crowded by the ^vingless lice and soon after developing 

 wings, spread to other leaves and trees to start new colonies. The pro- 

 portion of winged ones increased as the season advanced. About the 

 middle of ]\Iay last year at Grand Junction, when the leaves of the 

 trees had become heavily infested, not only winged but the wingless 

 lice were seen to commence migration in great numbers from peach 

 trees. By the last of May or the first days of June, scarcely a single 

 one could be found upon them. It was indeed interesting to witness 

 this phenomenal dispersion of plant lice. Each seemed anxious to for- 

 sake the peach leaves before its neighbor. Some days the air in badly 

 infested peach orchards would be filled with flying aphides. The 

 ground in such orchards would be thickly scattered with crawling, 



