CONTENTS. 
Page. 
Classification and synonomy 11 
Varieties - 12 
Common names 12 
Geographical distribution 13 
Original home 14 
Food plants 17 
Status of boll worm in foreign countries ... 19 
Economic status in the United States 21 
Injury to corn 21 
Injury to cotton , 23 
Injury to tomatoes ■ 25 
Distribution and destructiveness in relation to life zones 25 
Transition zone 26 
Upper Austral zone 27 
Carolinian area 27 
Upper Sonoran area 28 
Lower Austral zone 28 
Austroriparian area 28 
Lower Sonoran area 28 
; The bollworm in the western United States 29 
Farm methods in relation to bollworm injury 29 
Relation of weather to bollworm injury '. 32 
Injury to cotton from other causes than the bollworm 35 
Earlier investigations of the Department of Agriculture 37 
Life history 40 
Summary 40 
The egg 41 
Description- 41 
Oviposition 42 
Oviposition on corn 42 
Time and manner of oviposition 44 
Oviposition on cotton 45 
Time and manner of oviposition 45 
Distribution of eggs on cotton 46 
Oviposition on other plants 47 
Number of eggs laid by a single moth 48 
Deposition of infertile eggs 49 
Eggs remaining in the ovaries at death 49 
Effect of fertilization on egg laying 49 
Changes in external appearance 50 
Embryonic development 50 
Hatching 50 
(5) 
