ILLUSTRATIONS. 



PLATES. 



Page. 

 Plate I. Some of the more important plant-bugs which attack cotton bolls. 

 Fig. 1. — The conchuela (Pentatoma ligata). Fig. 2. — The brown 

 cotton-bug (Euschistus servus). Fig. 3. — The green soldier-bug 

 {Nezara hilaris) . Fig. 4. — Thyanta custator. Fig. 5. — Acanthoceph- 

 ala femorata. Fig. 6. — The leaf-footed plant-bug (Leptoglossus 

 phyllopus). Fig. 7. — ^The bordered plant-bug {Largus succinctus). 

 Fig. 8. — The cotton stainer (Dysdercus suturellus). Fig. 9. — Onco- 

 peltusfasciatus, showing egg of Tachinid parasite attached to upper 



side of head between the eyes Frontispiece. 



II. Effects of plant-bug attack on cotton bolls. Fig. 1. — Boll with sec- 

 tion of carpel removed to show plant-bug injury. Fig. 2. — Portion 

 of full-grown cotton boll showing lock of cotton ruined by destruc- 

 tion of seed at apex by Thyanta custator. Fig. 3. — Lint partly 

 removed from seeds to show discoloration by cotton stainer (Dys- 

 dercus suturellus). Fig. 4. — Decay of seeds in immature cotton boll 

 as a result of feeding by plant-bugs; no external evidence of in- 

 jury. Fig. 5. — Exterior of cotton boll injured by Calocoris rapidus. 

 Fig. 6. — Cross section of immature cotton seed damaged by Penta- 

 tomid bugs. Fig. 7. — Inside of carpel of cotton boll showing feed- 

 ing punctures by plant-bugs. Fig. 8. — Cotton boll showing exter- 

 nal spots referred to on page 16 16 



III. Effects of plant-bug attack on cotton bolls; egg and puparium of 



Tachinid parasite. Fig. 1. — Locks of a cotton boll shriveled by 

 the conchuela. Figs. 2-5. — Small Sea Island cotton bolls de- 

 stroyed by the cotton stainer. Fig. 6. — Nearly mature Sea Island 

 cotton boll opened to show damage by cotton stainer. Fig. 7. — 

 Same, with seeds and lint removed to show feeding punctures and 

 proliferation due to feeding by cotton stainer. Fig. 8. — Cotton boll 

 showing two locks damaged by four and six feeding punctures, re- 

 spectively, by the green soldier-bug {Nezara hilaris). Fig. 9.— 

 Head and thorax of the conchuela, showing egg of Tachinid para- 

 site, Gymnosoma fuliginosa, attached to side of prothorax at left. 

 Fig. 10. — Puparium of Tachinid parasite, Gymnosoma fuliginosa . . 18 



IV. A cotton plant, showing the bolls injured by the conchuela 18 



V. Fig. 1. — Egg-batch of conchuela, showing hatched and unhatched 



eggs. Fig. 2. — Egg-batch of conchuela from which 32 Procto- 

 trypid parasites ( Telenomus ashmeadi) have emerged 26 



TEXT FIGURES. 



Fig. 1. The conchuela {Pentatoma ligata) : Adult, egg-mass, eggs 26 



2. The conchuela: Nymph, first instar 27 



3. The conchuela: Nymph, second instar 27 



4. The conchuela: Nymph, third instar 28 



