IN("RKASK OF MORTALITY Wnil M(H{?: SP:V^ERE ATTACK. 25 



Table VIIT. — Comjmristtn offonr varietus, Kick hnrin(j orer 't(X) observations in TahlcVIl , 

 showing average fyerceniages of mortatiti/ and injhtence of proliferation thereon. 



\'aricty. 



Squares with proliferation. ' Squares without prolifemtion. 



Num- 



luT of 



sqniiros 



exain- 



inod. 



Num- 

 ber of 

 squii res 

 with 

 prolif- 

 era- 

 tion. 



Nuiii 



Num- 

 ber of 



Num- 



Per 



Aver- 

 ago 



Territory 1,5*18 



KinK 1,525 



Shine (>72 



Native 567 



828 

 812 

 3.34 

 259 



.or of I '7',''ent «^"?;;''-^ ber cent of nmii- 

 weevil "'ff.'^f'^ "-'^.^ wocvil stages bor of 



stages 

 found. 



703 

 250 

 288 

 172 



found 

 dead. 



22.4 

 16.7 

 27.1 

 17.5 



nro if. stages '"""(• ftage.s 

 proni- fn,,nj_ ^„„,. „„. ,#v 



ora- 

 tion. 



per 100 

 squares. 



740 

 713 

 338 

 308 



422 

 331 

 253 

 177 



Average 

 increase 

 in rate of 

 mortal- 

 ity due 

 to pro- 

 lifera- 

 tion. 



18.7 

 16.1 

 18.0 

 15.8 



In squares having: proliferation the range in mortality varies 

 between 16.7 per cent for King and 27.1 per cent for Shine. In 

 squares without ])roliferation tliis range is between 0.6 per cent for 

 King and 9.1 per cent for Shine. The most striking point in this com- 

 parison is sliown in the last column of the table giving the average 

 increase in mortality due to proliferation in each variety. In sj)ite of 

 the variations of 8.5 and 10.4 in the preceding percentage columns 

 there is shown in the last column a variation of only 2.9 per cent. The 

 unfavorable influence of ]u-oliferation apj^ears, therefore, to be very 

 nearly constant in difl'erent varieties, instead of varying widely, as 

 early indications had led us to anticipate that it might do. 



In respect to the rapidity of maturity these four varieties may be 

 fairly considered as ranging fi'om the very earliest to the late varieties. 

 Rapid maturing or, in other words, "short season" cotton does not 

 seem to increase esjiecially either the formation of proliferation or the 

 percentage of mortality occurring in the s(piares. 



INCREASE OF MORTALITY ACCOMPANYING MORE SEVERE ATTACK. 



While only injured scpiares were selected for these examinations 

 there was a dillVrence in tlie severity of the weevil attack in dill'erent 

 fields. It was evident during the growing season that the field in 

 which most of the data for Sliine was obtained was being more severely 

 injured than any other in which observations were made. The figures 

 show some very interesting resuhs of tiiis condition, if, indeed, they 

 do not indicate the explanation for the increa.sed severity of the 

 attack. The four varieties may be arranged in the order of the 

 increasing proportion of weevil stages to number of stpiares exainine<l. 

 The figures for the number of weevil stages found and for the stages 

 dead in squares without proliferation are reduced to the common basis 

 of 1 .000 squares for convenience in comparing. 



