29 



Distribution of boUiconn er/gs upon cotton plants. 



■ Eggs. 



Leaves, upper surface 191 



Leaves, lower surface 194 



Squares 326 



Flowers 110 



Bolls 120 



Growing tips „ 46 



Stems 64 



Petioles 29 



Weeds 20 



Objects on ground 21 



Dead leaves 20 



The total number of plants oviposited on by these 25 moths was 

 1,175. All larvfe hatching- from eggs deposited elsewhere than on 

 the squares and flowers may, for reasons to be given, be considered 

 as capable of destruction by poison. Therefore, of the 1,111 eggs 

 deposited, 705, or about 62 per cent, would fall in this class. 



On account of the important bearing on the subject of poisoning, 

 as before mentioned, the habits of the newly hatched larva) have been 

 quite carefully studied. Immediately upon its escape from the Qgg 

 the little larva devours its deserted egg-shell and soon afterwards 

 begins a restless search for food. If it hatches from an ^gg placed 

 upon a scjuare or flower, it ma}^ soon efi'ect an entrance, but if situated 

 elsewhere, as on a leaf, it may wander about here and there, fre- 

 quentl}' tasting or rasping the epidermis of the leaf or other portion 

 of the plant where it may be, in its eft'orts to find suitable food. 



This apparently aimless search is often continued for several hours. 

 The same path is often crossed and recrossed many times with short 

 intervals of surface feeding along the way. Many of these minute 

 larva? perish in their attempts to And suitable food; others succeed in 

 reaching- some tender-growing portion of the plant, as the terminal 

 bud of unfolded leaves, which is soon penetrated. Although consid- 

 erable traveling may be done later in the search for fresh food, but 

 little food is taken on the surface. Larvfe which hatch from eggs 

 placed upon bolls may rasp the epidermis but are unable to enter except 

 in case of the smallest bolls. Therefore these, as well as larvae from 

 Qggs placed upon the leaves, petioles, stems, etc., are compelled to 

 seek more tender portions. This period of what might be called 

 external feeding varies greatl}'^ in dift'erent individuals, lasting, as a 

 rule, probably from a few hours to a da}^, or even more. 



Considering the above facts, the necessity of appl^nng poisons at 

 the proper time is apparent. No arbitrary date may be given, owing 

 to the variability of the time at Avhich the larvoe begin to hatch in 

 destructive numbers in different localities. However, the planter may 

 determine this time approximately by careful observation. AVhen 



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