METHOD OK S'IM'DY. 9 



point at which prohrcratioii ho<j^iiis. In most cases the |)roHreriit ioii 

 appears to bei!:in very near to tlie j)oint of injui\ , Imt from tliat point 

 it may spread tlironj^^li an entire lock, or to all the inner parts of an 

 injnreil hud. 



MHTMOl) OK STl'DV. 



As the sifxnificanee of thes(> observations camo to be more fully 

 :ippreciated it was believed that they contained at least a. su<i:<^est ion 

 as to some very promising lines of work in (he problem of controIlin<ij 

 the we(>vil. Accord inii:ly, it has been necessary to study carefully the 

 nature of the j)henomen()n, conditions of climate, soil, fertilizer, and 

 variety of cotton which aO'ected the. occurrence of proliferation. 

 Observations hav(\ therefore, been made u|)on (piite a lari^^e mimber of 

 varieties, and in locations ran<^in<i: from Victoria to ])allas, Tex., upon 

 various types of soil, and in connection with A'arious experiments with 

 fertilizers and difl'erent conditions of cultivation. From a comparison 

 of the results thus ol)taini'd it was hojX'd that some factors mi^ht be 

 found which could be used practically in increasin<j^ ])roliferation, and 

 thus rendering!: it jnore efl'ective as a factor in controllini:; the weevil. 

 In many cases the results of the work have been ([uite different from 

 those aiUicipat(M|, but enou^^h has been learned to justify the assertion 

 that at present i)roliferation is a mor(> imj^ortaiit factor in retarding the 

 nudtijjlication oi the weevil than are the parasites which have thus far 

 been found. 



Larixe munbers of s<|uare^^ and bolls have be(>n carefully examined 

 in obtaining; these records. In the examination of ])olls, the lock 

 lias been made the unit rather than the boll. As a o^eneral rule, a 

 larva confines its injury almost, if not entirely, to the lock within 

 which the e<x^ was oriijinally placed. Quite frecpiently two or more 

 larva^ occur within a lock, but even in such cases the injury does not 

 often extend throu^di the scjitum or ])artition wliich sc^jiarates the 

 locks. 



In makini; a comparison of varieties considerable care is re<piired 

 in subdivi(lin<; the classes of observations in order to render the influ- 

 ential conditions sulliciently uniform to make the ()bs(>rvations fairly 

 comparable and wherever possible to reduce the fundamental causes 

 or stimuli producing; variations in the |)ioliferat ion to one essential 

 factor. While the pluMiomenon in bolls is of a similar nature to 

 that in s(|uares, conditions in these two cases are so diU'ercnt that 

 the results are not strictly comparable, and therefore se|)arate tables 

 have been made for sfpiares and bolls. The ell'ects of feedinir and 

 eri«; punctures also call foi" se])arate classification. This treatment 

 of the subject necessarily multiplies th(> number of tables, but we 

 hope that it will render the results more easily intelli^Mble. The 

 personal etpnition of the observer has been e(|ualized by combining 

 the records made by a numl)er of investigators. 

 31022— No. 59— (X) 2 



