GO THE MEXICAN COTTON-BOLL WEEVIL. 



Table XXII. — Seasonal rate of oci position of the boll weevil. 



Place. 



Victoria, Tex 



Do 



Do. 



Do 



Do.'. ... 



Do.' 



Do 



Terrell, Tex.. 

 Dallas, Tex.. 



Do 



Tallulah, La. 



Do. 2 



Total. 



Average. 



Time. 



Aug.-Dec.,1902. 

 Sept.-Oct.,1902. 



....do 



Oct.-Dec.,1902.. 

 May-July, 1903.. 



June-Sept., 1903. 



Aug., 1904 



Sept., 1904 



J ul v- Aug., 1905. 

 Aug.-Sept.,1905. 

 June-Aug.,1910. 

 Aug.-Oct.,1910. 



Num- 

 ber of 

 Females. 



351 



3 24 

 3 

 4 

 2 

 3 

 3 9 

 34 



154 



Num- 

 ber of 

 weevil 



days. 



135 



247 



23 



13 



352 



2,018 



1.395 



21 



12 



23 



108 



310 



183 





A ver- 



age 



period 

 of ovi- 

 DOSi- 



tion. 



Total 



number 



of eggs. 



135 

 6 



31 



255 



L,248 



227 



236 



990 

 5,254 

 3,541 



112 

 55 

 81 



233 

 1,830 



887 



14.949 



Aver " 1 iY" Maxi " 

 age I t ^r, mum 



mun,,1 ' r number number 



ofeggj 



dailv. . I r , 

 u * female. 



1.88 

 5.05 

 2.37 

 4.54 

 2.81 

 2.60 

 2.53 

 5.32 

 4.56 

 • 

 2. 15 

 5.90 

 4.85 



3.13 



255. 

 31.2 



116.0 



110.0 

 103.0 

 147.5 

 37.3 

 13.7 

 40.5 

 77.6 

 203.3 

 221.7 



97.07 



m one 



dav. 



1 Hibernated weevils. 



2 First generation weevils. 



3 Observed for entire opposition period and used in discussion of fecundity. 



shown by the following diagram 



90 





Vc/AfBS/? of Eggs 

 ' 2 3 4 S 6 

















\ 



%80 



ll? 











/ 



' 











/ 



J 







1 

 1 







! 













1 













fin 

















The influence of temperature upon the rate of opposition may be 



(fig. 6), which expresses in a single 

 line the mean number of eggs laid daily at a 

 given temperature. There is, of course, more 

 or less fluctuation from the mean, and it is 

 due mostly to differences in humidity. 



The maximum number of eggs deposited by 

 any weevil in one day has been recorded by 

 Mr. Cushman as 20 at Tallulah. La. At Vic- 

 toria, Tex., Dr. Morrill recorded two weevils 

 to have laid 108 eggs in three days, or at the 

 rate of 18 eggs per day. Dr. Morrill found 

 that the size of weevils did not affect the rate 

 per day, as four very small females laid 761 

 eggs at the rate of 3.3 eggs per day. It will 

 be noticed that this rate is higher than the 

 average of all the records in Table XXII. The 

 number of eggs produced on the first day of 

 oviposition varies from one to seven. About 

 ^u'en^e^te^S^ 67 P er cen ^ of \ tlie weevils at Victoria were 



on average rate of oviposi- found to Oviposit fewer than three C2^S Oil the 

 tion of boll weevil. (Orig- /. + i w r °° 



inai.) nrst day. 



IS THE FECUNDITY OF THE WEEVIL DECREASING J 1 



In view of the fact that recent observations have shown a decrease 

 in the fecundity of the gipsy moth in Massachusetts, 1 we have 

 selected from the foregoing table (Table XXII) on the seasonal rate 

 of oviposition the rather meager data bearing on the question of 



whether the fecundity of the boll weevil is decreasing. We find 76 



Howard and Fiske, Bull. 91, Bur. Ent., U. S. Dept. Agr., pp. 109, 110, 1911. 



