HEMIPTERA 



APHINA. 



271 



Hyadaphis umbellulariae Dav. 

 Hyalopterus arundinis Fabr. 

 Lachnus ainifoliae Fitch. 



californicus Ess. 

 Macrosiphum albifrons Ess. 



Isevigatae Ess. 

 Myzus cerasi Fabr. 

 Nectarophora avenae Fabr. 



baccharidis Clarke. 



californica Clarke. 



citrifolii Ash. 



jasmin! Clarke. 



lycopersici Clarke. 



rhamni Clarke. 



ros3e(Linn.) 



sonchella Mon. 



valerianise Clarke. 

 Pemphigus betae Doane. 



fraxinidipetalae Ess. 



populicauiis Fitch. 



radicola Es. 

 Phorodon humuli Fitch. 



scrophulariae Thorn. 

 Phylloxera vastatrix Pla. 

 Phopalosiphum dianthi Schr. 



viola; Es. 

 Schizoneura americana Ril. 



lanigera Haus. 



querci Fitch. 

 Siphocoryne foeniculi Pas. 

 Siphonophora citrifolii — Nectarophora. 



ALEURODID/E. 



Figure 249. Eggs of the citrus wliite fly. 



Tile white flies resemble scale insects in the nymph stage but both sexes 

 are winged as adults. The most injurious species is the one at?:;acking 

 citrus trees, A. citri, which has only recently established itself in this state. 

 SeeCalifornia Circulars 30 and 32. 

 Aleurodes acaciae Quain. citri R. & H. 



amnicola Bemis. coronatus Quain. 



