ILLUSTRATIONS 



PLATES. 



Page. 



Plate I. Outdoor rearing shelters 12 



II. Outdoor rearing shelters used in life-history studies on the yellow 



clover aphis 24 



TEXT FIGURES. 



Fig. 1. Toxoptera muhlenbergix: Winged \ivi])aTO\is iemale and autennsi 2 



2. Tozoptera muhlenbergise: Wingless viviparous female 3 



3. Toxoptera muhlenbergise: Wingless male and antenna 4 



4. Toxoptera muhlenbergise: Wingless oviparous female, antenna, hind 



tibia 5 



5. Toxoptera muhlenbergise: Eggs 6 



6. Toxoptera muhlenbergise: Eggs deposited in curled leaf sheath 13 



7. Lamp-chimney molting cage used in rearing aphides 14 



8. Lamp-chimney generation cage used in rearing aphides 15 



9. Lamp-chimney stock cage used in rearing aphides 15 



10. Map showing distribution of the yellow clover aphis (Callipterus 



trifolii) in the United States 19 



11. The yellow clover aphis {Callipterus trifolii): Winged viviparous 



female and details 21 



12. The yellow clover aphis: Wingless viviparous female and details 23 



13. 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 yellow 



clover aphis, La Fayette, Ind., 1913 34 



IV 



