N I) E X 



Page. 



Abbasi cotton, flaring of squares 40 



Acacia, symbiotic specialization 29 



Acclimatization of Kekchi cotton 17 



Accommodation, direct responses to external conditions 69 



Adaptation, discussion 68, 69 



explained by natural selection 68 



Adaptations, attractive to the kelep 73 



classification 72 



climatic effect 10, 43, 44 



commercial value 76 



historical treatment 72 



nature and causes 67 



periods when most effective 74 



of Asiatic cottons unknown 32 



Kekchi and Rabinal cottons 73 



Kidney, Pachon, San Lucas Sea Island, and Upland cottons . . 74 



summary 72 



to avoid weevils 72 



exclude weevils 73 



prevent development of weevil larvae 73 



A laptive characters, extent 69 



origin .- 67 



Aidin cotton, character - 53 



Allen cotton, earlier than King in Guatemala . 17 



Anthonomus, behavior of species related to boll weevil 48 



Antidromy in cotton 19 



Antigua, Guatemala, culture of brown cotton 70 



Ants caring for plant lice 39 



injurious to cotton 39 



no protection against weevils 39 



plants domesticated by 29 



Aphids injurious to cotton 39 



Aph is gossi/pii, infesting plants at Rabinal, Guatemala 39 



Arid climate, inactive nectaries an adaptive result 24 



regions, behavior of cotton . 43, 44, 45 



type of plant adapted 1 20 



Artificial selection, an indefinite term 70 



Ashmead, William H. , ants identified 39 



Asiatic cottons, comparison with other varieties 53 



nectaries 28, 31 



Bacterial diseases following weevil injuries 62 



Bidens pilosa, nectar produced 36 



Birds, value as weevil destroyers 42 



Boll weevil larvae, adaptations to prevent development 73 



behavior in Guatemala and Texas 47 



destruction by drying out of squares 43 



proliferation 46 



development in bolls 46 



effect of opening of flowers 47, 63 



rapid development in buds 63 



weevils, absence from Eastern Hemisphere 32 



Mexican plateau region 11 



adaptations to avoid 72 



exclude 73 



aid to cross-fertilization 55 



