ILLUSTRATIONS 
PLATES. 
Page. 
Plate I. Map showing distribution of boll worm in world Frontispiece 
II. Life zones of the United States 24 
III. Fig. 1.— Egg of the bollworm 40 
Figs. 2-7. — Respective larval instars 40 
Fig. 8.— Pupa 40 
Fig. 9.— Moth 40 
IV. Fig. 1.— Field of corn of age to attract moths for oviposition 44 
Fig. 2. — Bollworm eggs, enlarged, seen from above 44 
V. Tip of ear of corn showing bollworm eggs on silks 44 
VI. Fig. 1. — Bollworm on leaf stalk of cotton plant 56 
Fig. 2. — Variation in markings of larv?e, lateral view 56 
Fig. 3. — Variation in markings of larvse, dorsal view 56 
Fig. 4. — Dorsal pattern of markings of dark-brown larva 56 
VII. Fig. ]. — Young corn plant, showing injury to "bud" by bollworm. 68 
Fig. 2. — Bollworm and its work in corn tassel 68 
^ VIII. Fig. 1. — Bollworm and its injury in ear of field corn 68 
Fig. 2. — Bollworm and its injury in ear of sweet corn 68 
IX. Fig. 1. — Bollworm and its injury in cotton flower 68 
Fig. 2. — Cotton flower destroyed by bollworm 68 
Fig. 3. — Injury of very young larva to cotton square 68 
Fig. 4. — On the right, "flared" cotton square due to bollworm 
injury ; on left, normal square 68 
Fig. 5. — Bollworm destroying young cotton boll 68 
X. Fig. 1. — Bollworm eating into a half-grown cotton boll 68 
Fig. 2. — ^Bollworm boring into full-sized cotton boll _ 68 
Fig. '3. — Work of bollworm in interior of cotton boll 68 
Fig. 4. — Cotton boll only partially destroyed by bollworm, two 
"locks" open 68 
XI. Fig. 1. — Bollworm injury to tobacco 68 
Fig. 2. — Bollworm and its injm-y to tomato 68 
Fig. 3. — Bollworm boring into green peach 68 
Fig. 4. — Bollworm attacking okra 68 
Fig. 5.— Bollworm boring into cowpea pod 68 
XII. Fig. 1. — Larva entering soil for pupation 80 
Fig. 2. — Shrunken appearance of larvce just before molting into pupa 
stage - 80 
Fig. 3. — Larva in its "cocoon, " as made in sandy soil 80 
Fig. 4. — Bollworm pupae 80 
XIII. Fig. 1. — Pupal cell of bollworm in soil 80 
Fig. 2. — Plaster of Paris casts of pupal cells 80 
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