BEAKED INSECTS 



389 



diseased spots (K.St.), which are followed by the slow decay of the tree. 

 The colonies of this plant louse (B.A.) are invariably enveloped in a white, 

 waxy, wool-like substance secreted from the abdominal somites (u.W.), 

 and protecting the insects from enemies. (Compare with frog-hopper.) 

 From eight to eleven generations of wingless females (u.W.) are suc- 



VINE APHIS. 



Swellings at root of vine (natural size) ; u.W. and u.W.l., wingless females viewed side- 

 ways and from below (strongly magnified) ; u.W., shown sucking at the root ; below the 

 body the sheath of the sucking proboscis (inserted into the root) ; in u.W.l. the proboscis 

 is contained within its sheath ; g.W., winged female (strongly magnified) ; next to it the 

 same insect about natural size. 



ceeded in late summer by winged females (g.W.). These spread them- 

 selves abroad, and produce on the under side of leaves (g.W.l.) wingless 

 males and females (M. and W.). Each of the latter lays a " winter 

 egg " (in the female [W.] shown in the illustration the egg is discernible 



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