16 



FAEMERS BULLETIN 804. 



migrants of the rosy aphis. The two species, however, can be dis- 

 tinguished readily by the length of the honey tubes. In the rosy 

 aphis these are very long, while in the clover aphis they are short. 



The forms of this species which 

 live on clover are pink. 



Fig. 13. — The woolly appi'^ ap 

 noma lanigcriim) : Ci>louii- 

 shoots. (Original.) 



s (Erio- 

 n apple 



SKASONAL HISTORY. 



The eggs of the clover aphis are 

 laid upon the apple in much the 

 same manner as those of the 

 species already mentioned. The 

 stem-mothers, which are hatched 

 considerably earlier than those of 

 the rosy aphis and the green apple 

 aphis, give birth to wingecl and 

 wingless forms, which in turn pro- 

 duce young, some of which become 

 winged, while the others remain 

 wingless. As a rule most of the 

 insects have become winged by 

 early summer, although some 

 wingless colonies occur during the 

 summer on apple. These winged 

 forms fly to clovers, and settling 

 upon the stems produce wingless 

 young. These and succeeding 

 generations, which may contain 

 Avinged individuals, pass down to 

 the crown of the clover plants, 

 and here the species lives through- 

 out the summer. During October 

 numerous fall migrants are pro- 

 duced upon, the clovers and fly to 

 the apple, where they give birth 

 to the young egg-laying females. 

 Winged males produced upon the 

 clovers follow the fall migrants 

 the females, which later deposit 



to the apple, and here mate with 

 their eggs. 



THE WOOLLY APPLE APHIS.i 



The woolly apple aphis is often in .evidence in sunmier on the trunk, 

 branches, and tAvigs of the apple as bluish white cottony patches 

 (fig. 13) which hide the rusty or purplish brown aphids beneath. 



Eriosoma lanigcrum (Ilausm.) 



