RECENT STUDIES OF THE MEXICAN COTTON BOLL WEEVIL. 19 



The average number of eggs per day ranged from 1 to 8.2, with an 

 average of 3.3 eggs. This is also much less than the average for 

 either the hibernated or once copulated weevils. The maximum 

 number of eggs per day ranged from 5 to 14. In fact these weevils 

 showed a surprisingly low degree of fertility in all points. 



Fecundity of females of A. grandis in experiments not continued to 

 completion. — Many of the females in the various grandis generation 

 series were allowed to oviposit only a short time and then stopped 

 because of lack of squares. Some interesting data were secured 

 from some of these weevils, as is shown in Table X. 



Table X. — Fecundity of females of A. grandis in experiments not continued to 



completion. 



Oviposition started. 



Experi- 

 ment 

 closed. 



Oviposi- 

 tion. 



Total 



eggs. 



Eggs per day. 



Maximum. 



June 16. 

 June 17. 



Do. 

 July 7.. 



Do. 

 July 9.. 

 Sept. 8. 

 Sept. 9. 



June 20 

 July 2 

 July 11 

 July 12 

 ...do.... 

 ...do.... 

 Sept. 21 



Days. 

 5 

 16 

 25 

 6 

 6 

 4 



14 

 13 



20 

 147 

 318 

 45 

 99 

 31 

 53 

 73 



5.0 

 9.2 



12.7 

 7.5 



16.5 

 7.7 

 3.7 

 5.6 



Maximum . 

 Minimum . 



16.5 

 3.7 



This information is of principal value in giving maximum and 

 minimum records. One female in this lot gave the season's maxi- 

 mum record for eggs deposited in one day. This was 26 eggs. Inci- 

 dentally this is the highest number of eggs deposited by a single female 

 in one day on record. This female was allowed to continue deposi- 

 tion only 25 days, but in this time she deposited a total of 318 eggs, 

 or an average of 12.7 per day. 



Fecundity of typical A. g. ihurberise fed on cotton squares. — Three 

 pairs of pure thurberise, were mated on cotton squares in June, but 

 for some reason only one female deposited any eggs. This one 

 deposited 7 eggs with a maximum of 4 in 1 day and an average of 

 0.3 per day. These eggs were probably all fertile, as most of them, 

 at least, hatched. It is very hard to account for the fact that two 

 of these females laid no eggs and the other deposited so few. The 

 females of thurberise placed with grandis males at this same time 

 deposited a normal number of eggs. 



The fall series of pure thurberise mated on cotton squares gave 

 much better results, as is shown in Table XL 



