ILLUSTRATIONS 



PLATE. 



Page. 



Plate I. Fig. 1. — Geared traction sprayer, suitable for the treatment of sugar 



beets against the Hawaiian beet webworm .' . . 8 



Fig. 2. — Geared traction sprayer in operation in sugar-beet field 8 



TEXT FIGURES. 



Fig. 1. The Hawaiian beet webworm (Hymenia fascialis): Female moth 3 



2. The Hawaiian beet webworm: Egg. larva, pupa, details 4 



3. The southern beet webworm (Pachyzancla bipunctalis) : Moth, larva, 



pupa, details 19 



4. The imported cabbage webworm (Hellula undalis): Adult, larva, pupa. "28 



5. The imported cabbage webworm: Wing venation; head and antenna. . 28 



6. Exorista pyste, a parasite of the imported cabbage webworm 31 



7 . Small compressed-air sprayer 38 



8. Porosagrotis vetusta: Moth, larva 50 



9. The sugar-beet webworm (Loxostege sticticalis) : Moth «... 58 



10. The garden webworm (Loxostege similalis): Moth, larva, pupa, details. . 58 



11. A medium-sized sugar-beet plant defoliated by the sugar-beet web- 



worm in July 60 



12. Sugar beets defoliated by the sugar-beet webworm in July ; . . 61 



13. Large sugar-beet plants, showing defoliation and weakened roots due to 



attack by the sugar-beet webworm in August 62 



14. Field of young sugar beets destroyed by the sugar-beet webworm in 



June 63 



15. Barrel sprayer suitable for use against the sugar-beet webworm 64 



16. Barrel sprayer in action against the sugar-beet webworm 65 



17. Four-row attachment for beet sprayer 67 



18. Four-row attachment for beet sprayer 67 



19. Four-row attachment for beet sprayer 67 



20. Geared traction sprayer suitable for use against the sugar-beet webworm . 68 



21. Geared traction sprayer in action against the sugar-beet webworm 68 



22. Filling a traction sprayer for spraying against the sugar-beet webworm . . 69 



23. Type of Vermorel nozzles suitable for spraying sugar beets against the 



sugar-beet webworm 69 



24. The liorse-radish webworm' (Plutella armoracia) : Adult or moth, side 



view and with wings spread 72 



25. The horse-radish webworm: Larva, lateral and dorsal views 72 



26 . The horse-radish webworm : Pupa 73 



27 . The horse-radish webworm : Cocoon 73 



ERRATA. 



Page 33, line 7, for Agrdstis read Agrotis. 



Page 72, line 14, for scale like read scale-like. 



Page 76, last sentence, read, In this garden the larvx have evidently been prevented by 

 a hymenopterous parasite from causing much damage, and at present no artificial control 

 measures are necessary. 



