ELM LEAF CURL AND WOOLLY APPLE APHID. 253 



"The most active natural enemies of the woolly aphis in 

 Colorado have been predaceous insects. We have reared no 

 parasite from it, but, Aug. 21, 1908, Mr. L. C. Bragg brought 

 into my office a female Aphelinus mali busily ovipositing in 

 apterous females of this louse. Among the Coccinellids, Hip- 

 podauiia convergent is by far the most abundant destroyer of 

 this louse both upon the eastern and western slopes of the 

 mountains. Mr. E. P. Taylor also took H. sinuata, Coccinella 

 p-notata, C. monticola and C. transversalis feeding on this louse 

 in the orchards about Grand Junction, and we have noted H. 

 transveralis, C y-notata, C. monticola, C frigida, and C. 5- 

 notata (transversalis and transversoguttata) feeding upon it 

 in eastern Colorado. 



"Mr. Taylor also reared two syrphus flies at Grand Junction 

 on this louse, namely, Catabomba pyrastri Linn, and Hupeodes 

 valuer is O. S. 



"Lace-wing flies are also very destructive to Schizoneura 

 hmigera in Colorado, and especially upon the western slope in 

 the Grand Valley, where Mr. Taylor concluded that they did 

 more than all else to subdue the unusually severe outbreak of 

 this louse in that valley during the early summer of 1907. The 

 Capsid, Camptobrochus nebulosus Uhl, we have found a com- 

 mon feeder upon this and some other plant lice in Colorado." 

 (Gillette 1908)? 



FOOD PLANTS. 



Crataegus Crus-galli (lucida). Schizoneura crataegi Oestlund. Davis, 

 1910, p. 412. 



Crataegus punctata Jacq. Schizoneura crataegi Oestlund. Oestlund, 

 1887, P- 28. (Now considered lanigera by Professor Oest- 

 lund). 



Crataegus tomentosus L> Schizoneura crataegi Oestlund. Williams, 

 1910, p, 20. 



Crataegus sp. Schizoneura lanigera. Patch, 191237 p. 236. 



Pyrus mains L. Schizoneura lanigera Hausmann. Alwood, 1904. Gil- 

 lette and Taylor, 1908, p. 28. 



Pyrus sitchensis. Schizoneura lanigera. Patch, 19123, p. 236. (Also 

 on two other cultivated species of mountain ash). 



Ulmus americana L. Schizoneura americana. Riley and Schizoneura 

 rileyi Thomas (Eriosoma ulmi Riley). Patch, 19103. Wil- 

 liams, 1910. 



