10 CONTENTS. 



Seasonal history — Continued. Page. 



The egg ." 62 



Duration of egg stage G2 



Hatching 64 



Hatching of eggs laid outside of cotton fruit 64 



Eating of eggs deposited outside 64 



Percentage of eggs that hatch 65 



The larva 65 



Food habits 65 



Growth 65 



Molts 66 



Duration of larval stage 6o 



Pupal cells 67 



Pupation 67 



The pupa 67 



Activity 67 



Duration of pupal stage 67 



Percentage of weevils developed from infested squares 68 



Life cycle 69 



Duration of life cycle 69 



Sexual variations 69 



Variations due to location of developing stage 69 



Variations due to time of falling of infested squares 69 



Variations due to temperature 70 



Variations of development in bolls 72 



Miscellaneous variations 72 



Development of weevils in the squares which never fall 73 



Development during winter 73 



Seasonal abundance 74 



Broods or generations 74 



Possible annual progeny of one pair of hibernated weevils 76 



Progress of infestation in fields 77 



Effect of maximum infestation upon weevil multiplication 79 



Status examinations 80 



Relation of weevils to top crop 81 



Variations in abundance of the weevil from year to year 83 



Natural dissemination 85 



Spring search for cotton 85 



Spring spread within the field '. 86 



Summer flights 86 



Fall dispersion 87 



Hibernation flight 90 



Other forms of natural spread 90 



Artificial dissemination 91 



Movement of seed cotton 91 



Movement of cotton seed 91 



Baled cotton 93 



Passing vehicles 93 



Movement of farm hands 93 



Unexplained sporadic occurrences 94 



Intentional transportation of the weevil 94 



Hibernation 94 



Methods of study of hibernation 95 



Entrance into hibernation 96 



Sources of weevils entering hibernation 96 



Stages entering hibernation 96 



Time of entering hibernation 97 



Number of adult weevils entering hibernation 98 



Shelter during hibernation 100 



Activity during the hibernation period 103 



Duration of hibernation period 103 



Average length of hibernation period 103 



Relation of shelter to duration of hibernation 105 



Emergence from hibernation 107 



Time of emergence 107 



Rate of emergence 108 



Survival of hibernated weevils 110 



Relation of fall destruction to survival Ill 



