28 



PAPERS ON THE COTTON BOLL WEEVIL, ETC. 



injury done depends upon the abundance of these broods, which 

 depends largely upon the time of appearance and also upon the relative 

 abundance of the hibernating brood. - 



MORTALITY OF SUMMER BROODS. 



The mortality occurring in summer and fall broods may properly 

 be distinguished from that among weevils which hibernate, for in the 

 summer the greatest mortality occurs in the immature stages. The 

 number of weevils developing from squares in which eggs have been 

 laid is shown in Table IV. 



Table IV. — Percentage of weevils from infested squares. 



Lot. 



10 

 11 

 12 

 13 



Date. 



AVhere picked and how kept. 



Weighted 

 j of squares, emerged, ^^^^^'^l 



Number Per cent 



May —1902 



July 8, 1904 



Sept. 10, 1903 

 Sept. — , 1903 



Picked from ground: phiced in cloth bags 

 and kept in laboratory under dry condi- 

 tions 



Picked from ground; kept under fairly 

 normal conditic )ns 



do 



do 



Sept. 21,1903 do 



Total of lots 2, 3, 4, and 5 . . 

 Total of lots 1, 2, 3, 4. and 5 



11,250 



1,522 

 675 

 350 



377 



23.5 



39 

 30 

 34 

 23 



23.5 



Sept. — ,1903 ' Picked from plants; « kept on moist soil 



Sept. 21,1903 I Picked from ground; kept between shaded 



rows 



do do 



Total of lots 7 and 8.... 

 Total of lots 6, 7, and 8. 



July 15,1904 



Sept. 11,1903 

 Sept. 22, 1903 

 Sept. 11, 1903 



Picked from ground, under screen; placed 



in jtart sun 



Picked from ground; placed in sun 



Picked from plants; <f placed in sun 



Picked from ground; placed in sun 



Picked from plants; « placed in sun 



Sept. 21,1903 



Total of lots 9, 10, 11. 12,13 



2 



,924 



14 



.174 



162 



200 

 43 



243 



405 



40 



39.5 

 30 



400 

 210 



68 

 354 



91 



1, 123 



9.0 



2.3 



2.9 







1.1 



34.3 

 25i7 

 40 



37.8 

 38.7 



9.0 



1.1 



3.9 



a Picked from plants when squares would drop off by touching them. 



Lot 1 is based upon the following note made b}^ Mr. Wilmon 

 Newell. During May, 1902, Professor Malh^ gathered infested squares 

 in fields along the Brazos River below Wellborn. About 1^ bushels 

 of these squares were brought to College Station, sewn up in cheese-cloth 

 sacks, and weevils allowed to hatch. June 15 the weevils were picked 

 out and by careful measurement there were 115 c. c. of them, and 15 

 c. c. contained 31:5 weevils, or 1,763 weevils to a bushel. Subsequently 

 we have found about 7,500 squares in a bushel, thus indicating that 

 only about 23.5 per cent produced weevils. The squares were kept 

 in the laboratory in a dr}^ place, and the lack of moisture may proba- 

 bly account for the low percentage producing adults. In another 

 test 2,921: squares gave a weighted average of 34 per cent producing 

 weevils. These were picked up and kept under fairly normal condi- 



