INFLUENCE OF PERIOD OF INFESTATION. 



51 



of locations which will benefit most largely by the average effecl Lveness 



of these factors of natural control. 



INFLUENCE OF PERIOD 



OF INFESTATION 

 CONTROL. 



UPON NATURAL 



A rearrangement of the data given in Tables III and V may be used 

 to give a comparison of the results according to the classes of forms 

 examined for Louisiana and for Texas. The separation of the data 

 for the two States is made to enable a comparison as to mortality in 

 a recently infested area, as in Louisiana, with an area which has been 

 infested for a considerable time, as is the case with nearly all the 

 localities examined in Texas. 



Table X. — Summary of results showing mortality in Louisiana and Texas resulting 

 from heat or drying, ants, and parasites. 





Total 

 number 



of 

 forms 

 exam- 

 ined. 



Total 

 number 



of 

 weevil 

 stages 

 found. 



Total 

 number 



of 

 weevil 

 stages 

 dead. 





Weevil stages killed. 



State and class of 



Total 

 mor- 

 tality 



by 



three 



causes. 



Heat or dry- Ants _ 



Parasites. 



fruit. 



Num- 

 ber. 



Per 



cent 

 of total 

 stages. 



Num- 

 ber. 



Per 



cent 



of total 



stages. 



Num- 

 ber. 



Ter 



cent 



of total 



stages. 



Louisiana: 



Hanging bolls 



Hanging squares. . 



2,955 



1,208 

 2.000 

 4,170 



1,103 

 847 

 599 



2,508 



Per ct. 



458 | 39.4 



519 | 01.3 



200 ! 33.4 



1,031 41.1 



137 

 175 

 54 

 100 



11.8 



20.7 



9.0 



0.4 



252 



274 

 141 

 859 



21.7 

 32.3 

 23.5 



35.7 



69 



70 

 5 

 12 



0.0 

 8.3 

 0.8 



Fallen squares 



0.7 



Total, Louisiana. 



10,999 



5,117 



2,208 j 43.2 



526 



10 3 



1,526 



29.8 



156 



3.0 



Texas: 



Hanging bolls 



Hanging squares. . 



Fallen bolls 



Fallen squares 



14,404 



5, 730 



20,079 



35, 738 



4.270 



3, 383 



4,019 



22,202 



1,192 



1,708 



1.323 



13,854 



27.0 

 50. 5 

 32 9 

 62. 7 



289 



029 



473 



0,141 



0.8 

 18.0 

 11.8 

 27.8 



650 



000 



810 



0,947 



15.2 

 18.2 

 20.2 

 31.3 



253 



470 



40 



770 



6.0 

 13.9 

 1.0 

 3.5 



Total, Texas 



75,957 



33,874 



18.077 



53.5 



7,532 



22.3 



9,016 



20. 7 



1,533 



4.6 



Total, Louisiana 

 and Texas 



80, 950 



38, 991 



20, 285 



52. 



8,058 



20.7 



10, 542 



27.1 



1,689 



4.3 



Naturally the examinations in Texas cover a much larger number 

 of forms than do those in Louisiana, amounting to 87.4 per cent of 

 the total for the two States. The Louisiana forms show a slightly 

 greater proportion of weevil stages to forms examined than do those 

 from Texas, in the former case the proportion being one weevil stage 

 to each 2.15 forms, in the latter State one weevil stage per 2.25 forms. 

 This di [Terence is, of course, but slight. 



In comparing the mortality results for the two States it appears 

 that in Texas the total mortality averaged fully 10 per cent higher 

 than it did in Louisiana. The smaller mortality found in Louisiana, 

 being inevitably connected with a higher proportion of weevil develop- 

 ment, doubtless explains sufficiently the slightly higher proportion 

 of weevil stages to forms examined which was found in thai State. 

 A comparison of the mortality from each of the three factors shows 

 thai in Texas the mortality from heat or drying and from parasites 

 exceeds that from these causes in Louisiana., while in the latter State 

 the proportion of mortality due to the work of ants is slightly greater 



