ILLUSTRATIONS 



I'l.A'I'K. 



Page. 

 Pi.Ai'io II. OuUloor reariug shelters used in life-hislory studies on the yelloAV 



clover aphis. . , 24 



TEXT FIGURKS. 



Fid. 10. .Map showing distribuli(jn of liie yellow clover aphis {Callipterus tri- 



folii) in the United States 19 



11. The yellow clover aphis (Callipterus trifolii): Winged viviparous fe- 



male and details 11 



12. The yellow clover aphis: Wingless viviparous female and dc^tails 23 



l;). The yellow clover aphis: Winged male and antenna 24 



14. The yellow clover aphis: Wingless oviparous female and details 25 



15. Diagram showing periods and succession of generations in the yelloA\' 



clover aphis, La Fayette, Ind. , 1913 34 



IV 



