New York Agricultural Experiment Station. 587 



have but two, a pair of halteres terminated by hooks being in the 

 place of a second pair of wings. The male is light yellowish or rose 

 red in color. The life of this little creature is very short after it comes 

 forth as a mature insect, probably only a few days, as it dies soon 

 after performing its only function. We have thus seen that the 

 males and females when mature are two very distinct creatures in 

 appearance, resembling each other much less than some insects of 

 entirely different species. This, however, is characteristic of the 

 Coccidaj. 



Sumnim'y. — From the above we may summarize briefly, as to the 

 life-history and habits of this scale as it occurs in western New 

 York, as follows : 



Most of the young scales appear during the latter part of June 

 and early in July, 



During the summer they ai-e to be found upon the leaves, and 

 a few of them upon the tender twigs. They undoubtedly injure 

 the trees during this time by sucking the sap. They also secrete 

 honey dew, but grow but comparatively little. 



They abandon the leaves in the fall and attach themselves to the 

 under sides of the twigs and Jimbs, or even upon the trunks of the 

 trees. They do not feed or grow but remain dormant during the 

 winter. 



They are most exposed during the winter of any time during the 

 year and hence most easily reached by insecticides. 



In the spring the females grow very rapidly and secrete honey 

 dew. The -males can now be readily distinguished from the females. 

 They undergo complete metamorphosis and come forth supplied 

 with wings, while the females remain wingless and unable to move. 



The males die soon after reaching maturity, and the females die 

 with the production of the eggs, the integument becoming hard 

 and brittle, forming a covering for the eggs and also for the young 

 during a short period. 



There is but one brood during the year. 



Natural Enemies. 



Under this head are mentioned some of the predaceous and para- 

 sitic insects which have come under our observation as preying upon 

 the plum scale. 



Predaceous insect enemies. — The eggs of at least three species 

 of predaceous hemipterous insects were found among the scale 



