148 



Insect Pests. 



Tims in two Mays wc liave the WuijIIv .Apliis carrying on its 

 existence (luring tlie winter above ground: (l)as living viviparous 

 females; (2) in the egg stage near the base of the tree. Besides 



living on the trunk and other pans alio\'e ground, Srhr.oiicii I'n 

 laniiicrii lives (o)on the roots and around the stem below ground. 

 The forms found beneath the soil are just the same as those living 

 above it. There they breed in the same "way, prod>ice galled growths 

 on till' roots, swollen and cracked areas on the stem, and suck the 

 sap going to the plant. 



Xii ii\-a has as yet been detected fielow 



^^^^ the soil. The actmil root form, that is, the 



^^^^^^^ race that galls the roots, is augmented during 



^^^^^^^ the winter by migrants from above. These 



^^^^ff latter mainly affect the trunk tielow the 



Mpip* surface soil, aiul these may and du return in 



spring to become the aerial race. Moreover, 



tlie actual root form migrates to the trunk. 



As far as I have observed, this migration 



is not at an\- fixed period of time, but is 



spasmodic. 



The damage done by the root form in 

 this couDlry is certaiidy severe, but not to the same extent that it 

 is in parts of America. Stedman (1), in his most excellent work in 

 tracing this insect's life-history, shows that in ]\Iissouri it is the 



FIG. vr.\. 



\l-\ /■;. 



(i"\"rM 111' WOCILI.V .\PHIS .\M 

 SIIia\l',l,l,KD SKIN OK y. 



(i^Tfatly eiilai!4i-a. ) 



