8 ILLUSTRATIONS. 



Page. 

 Plate X. Fig. 1. — Burning machine experimented with as a method of 

 destroying the alfalfa weevil. Fig. 2. — Boxes containing para- 

 sites of the larvae and pupae of the alfalfa weevil, showing how 

 this material was imported from Italy. Fig. 3. — Boxes of para- 

 site material imported from Italy which contain egg parasites 



of the alfalfa weevil 32 



XI. Introduction of parasites of the alfalfa weevil. Figs. 1, 4. — Type 

 of cages in which larval and pupal parasites of the alfalfa weevil 

 were reared in the laboratory. Figs. 2, 3. — Boxes sealed and 

 fitted with glass tubes into which imported parasites emerged 



and were separated in the laboratory 36 



XII. Figs. 1, 2. — Field cages used in hibernation experiments on the 

 alfalfa weevil. Fig. 3. — Planting a colony of imported para- 

 sites of the alfalfa weevil in Utah in an alfalfa field 36 



XIII. Figs. 1, 2. — Laboratories of the Bureau of Entomology, United 

 States Department of Agriculture, at Salt Lake City and Mur- 

 ray, Utah 40 



TEXT FIGURES. 



Fig. 1. The alfalfa weevil (Phytonomus posticus) : Adult 10 



2. The clover-leaf weevil (Hypera punctata): Stages and work 16 



3. The alfalfa weevil: Eggs 17 



4. The alfalfa weevil: Larvae attacking foliage; eggs in stem 18 



5. The alfalfa weevil: Larva 21 



6. The alfalfa weevil: Cocoon 23 



7. The alfalfa weevil: Pupa 24 



8. The alfalfa weevil: Adults attacking sprig of alfalfa 24 



9. Nine-spotted lady-beetle ( Coccinella 9-notata) : Adult, larva 31 



10. Convergent lady-beetle (Hippodamia con vergens): Adult, pupa, larva.. 31 



11. The two-spotted Collops (Collops bipunctatus) : Adult 32 



12. A predaeeous mite, Pediculoides ventricosus: Adult female before the 



abdomen has become inflated with eggs and young 32 



13. Pediculoides ventricosus: Adult female after the abdomen has become 



inflated with eggs and young 32 



14. A predaeeous mite, Erythrseus arvensis: Adult. . 33 



15. Anaphes sp., a mymarid egg parasite of the alfalfa weevil 34 



16. Imported pteromalid egg parasite of the alfalfa weevil: Adult 35 



17. Larva of pteromalid egg parasite of the alfalfa weevil 36 



18. Pupa of pteromalid egg parasite of the alfalfa weevil 36 



19. Pteromalid parasite of larva and pupa of the alfalfa weevil: Adult 



female 37 



20. Pteromalid parasite of larva and pupa of the alfalfa weevil: Adult male. 37. 



21. Pteromalid parasite of larva and pupa of the alfalfa weevil, showing eggs 



in place and enlarged figure of same 38 



22. Pteromalid parasite of larva and pupa of the alfalfa weevil, showing 



parasite larva 38 



23. Larva of pteromalid parasite attacking pupa of alfalfa weevil 38 



24. Pupa of pteromalid parasite shown in figures 22 and 23 38 



25. Canidiella curculionis, a parasite of the alfalfa weevil: Adult female 39 



26. Jtoplectis masculator, a parasite of the alfalfa weevil: Adult female 40 



27. Cocoon of the alfalfa weevil, showing cocoon of the parasite Canidiella 



curculionis within 41 



