BROAD-NOSED GEAIN WEEVIL. 



Table 2. — Rate of oviposition of Caulophilus latinatus} 





Temperature. 



Number of eggs laid 

 by weevil No.— 



Date. 



Temperature. 



Number of eggs laid 

 by weevil No. — 



Date. 



Max. 



Min. 



Mean. 



1 



2 



3 



4 



5 



6 



7 



Max. 



Min. 



Mean. 



1 



2 



3 



4 



5 



6 



7 



1920. 

 Aug. 10 

 12 



" F. 

 94 

 95 

 95 

 95 

 97 

 94 

 90 

 92 

 96 

 98 

 89 

 92 

 84 

 89 

 75 

 82 

 80 

 84 

 88 

 88 

 87 

 88 

 84 

 86 

 85 

 86 

 78 

 75 

 81 

 83 

 76 



° F. 

 70 

 70 

 69 

 69 

 70 

 69 

 69 

 70 

 72 

 69 

 67 

 68 

 70 

 70 

 46 

 48 

 50 

 52 

 62 

 60 

 64 

 66 

 59 

 57 

 60 

 60 

 57 

 63 

 52 

 54 

 58 



° F. 



82 



82.5 



82 



82 



83.5 



81.5 



79.5 



81 



84 



83.5 



78 



80 



77 



79.5 



60.5 



65 



65 



68 



75 



74 



75.5 



77 



71.5 



71.5 



72.5 



73 



67.5 



53.5 



66.5 



68.5 



67 



1 

 1 

 2 

 2 

 1 

 1 

 1 

 2 

 4 

 2 

 2 

 3 

 4 

 4 

 2 

 1 

 

 

 

 

 2 

 2 

 1 

 2 

 1 

 2 

 

 

 1 

 

 



1 

 



1 

 1 

 1 

 2 

 2 

 2 

 1 

 2 

 1 

 3 

 2 

 2 

 1 

 2 

 

 

 

 

 2 

 2 



(6) 





1920. 



Nov. 29 



Dec. 1 



2 



7 



8 



13 



14 



38 



19 



26 



27 



1921. 



Jan. 1 



2 



7 



8 



13 



14 



18 



19 



23 



24 



Feb. 1 



2 



7 



8 



13 



14 



20 



21 



" F. 



77 

 71 

 70 

 78 

 72 

 84 

 75 

 70 

 75 

 78 

 84 



84 

 79 

 74 

 79 

 78 

 79 

 79 

 73 

 83 

 81 

 84 

 82 

 84 

 84 

 74 

 74 



" F. 

 48 

 58 

 41 

 59 

 58 

 55 

 67 

 36 

 37 

 44 

 68 



44 

 62 

 45 

 51 

 48 

 61 

 46 

 53 

 50 

 49 

 50 

 44 

 58 

 52 

 38 

 40 



° F. 



62.5 



64.5 



55.5 



68.5 



65 



69.5 



71 



53 



56 



61 



76 



64 



70.5 



59.5 



.65 



63 



70 



62.5 



63 



66.5 



65 



67 



63 



71 



68 



56 



57 



1 

 1 

 

 1 

 2 

 3 

 2 

 

 

 1 

 1 



1 

 1 

 1 

 



1 





 



1 

 1 

 1 



0) 







1 

 3 

 

 2 

 2 

 1 

 1 

 

 



1 

 1 



1 



2 

 

 

 1 

 

 2 

 

 1 

 

 

 

 1 

 1 

 

 



1 



1 







2 



2 



3- 



2 











1 



3 



2 

 2 

 1 

 





 2 

 2 

 

 

 (8) 



1 



1 

 1 

 1 

 1 

 2 

 2 

 

 

 1 

 4 



2 

 1 

 

 1 

 1 

 1 

 

 



1 

 1 





 



1 

 1 





 



(9) 



1 



(2) 



1 



1 



4 



3 



1 



2 







2 



1 



1 



1 



1 



1 







1 



1 



1 



1 



1 











1 



19 



(^) 



1 



1 



1 



1 



2 



2 



1 



1 



1 



2 



2 



1 



1 



















2 



2 



\ 

 2 

 2 

 1 

 

 1 

 1 

 1 













20 



1 



1 

 2 

 1 

 2 

 

 2 

 1 

 

 

 

 

 



1 



2 

 

 

 

 

 2 

 

 2 

 2 

 2 





::; 







1 



26 

 27 







2 

 1 



Sept. 4 









 



11 

 12 

 17 









 1 

 ? 



18 

 24 







? 



25 



1 

 1 

 

 

 

 

 

 

 



1 

 1 



1 





 



1 

 1 



1 





 



1 

 1 



1 



Oct. 1 

 2 







1 

 



8 











B. 9 







1 



m 15 







1 



16 

 26 







1 



1 



27 



Nov. 1 



2 







1 







1 



7 





■-'- 









1 



8 









? 



14 









1 



15 













20 









f. 



21 







80 



52 



66 









1 



28 



... 

















(•10) 

























1 The mean temperature of the crib in which these records were made is about 3° to 4° F. higher than 

 the outdoor temperature quoted in this table. 



2 Emerged Aug. 7, 1920. s Died Nov. 2, 1920. s Died Feb. 16, 1921. 



3 Emerged Aug. 9, 1920. s Died Nov. 4, 1920. » Died Feb. 19, J921. 

 * Emerged Oct. 12, 1920. ' Died Feb. 1, 1920. w Still aUve. 



EGG STAGE. 



During the summer months, with the temperature ranging from 

 65° to 99° F., with a mean of 81°, the egg hatches in four days. As 

 the weather gets colder the incubation period gradually lengthens 

 until, in the coldest winter months, with the temperature ranging 

 from 34° to 88° F., with a mean of 62°, from 10 to 14 days is the 

 normal length of the period. 



LARVAL PERIOD. 



When the egg is placed in the germ or in the starch of the kernel 

 the young grub, breaking through the bottom of the shell, finds a 

 plentiful supply of food. Development of the grub is most rapid 

 when it is located in the germ. Progress is a little slower in the 

 seft starch, while development in the tough horny "endosperm is 

 very slow and the larval period is greatly prolonged. 



NUMBER OF LARVAL STAGES. 



There are three larval stages. The first two are about equal in 

 length, while the third is slightly longer. Table 3 gives data showing 

 the variation in the length of these stages at different times of the year. 

 103755— 22— Bull. 1085 2 



