PINK BOLLWOEM OF COTTON IN MEXICO. 



19 



dried. Afterward the moth crawls off and hides until dark, if 

 issuance has taken place during the day. What course is followed 

 when issuance takes place at night was never observed. 



Time of Day Moths Emerge. 



The moths emerge from the pupse at all hours of the day and 

 night under laboratory conditions, where the temperature and 

 humidity are more or less uniform. From Table VIII it can be seen 

 that between the morning examinations and the afternoon exami- 

 nations, 421 moths emerged in 134.5 hours, an average of 3.1 moths 

 per hour, and that 348 moths emerged between the afternoon exami- 

 nations and the morning examinations in 301 hours with an average 

 of 1.1 moths per hour. About three times as many moths emerged 

 during the day as emerged per hour during the night. 



Table VIII. — Time of day of emergence of the adult P. gossypiella. 





Morning exami- 



Afternoon exami- 





Morning exami- 



Afternoon exami- 





nation. 



nation. 





nation. 



nation. 



Date. 









Date. 



























Time. 



Number 

 of adults. 



Time. 



Number 

 of adults. 





Time. 



Number 

 of adults. 



Time. 



Number 

 ofadults. 



1919. 











1919. 











May 22 



10.00 



C 1 ) 



5.25 



27 



June 4 



10.00 



(') 



5.30 



9 



May 23 



9.30 



16 



5.30 



5 



June 5 



10.00 



22 



6.00 



19 



May 24 



9.30 



2 



5.30 



17 



june 6 



10.00 



25 



6.00 



20 



May 25 



10.30 



15 



5.30 



25 



June 7 



10.00 



14 



( 2 ) 



( 2 ) 



May 26 



9.30 



10 



5.00 



27 



June 8 



10.00 



(') 



( 2 ) 



( 2 ) 



May 27 



9.30 



15 



5.30 



26 



June 9 



10.00 



(') 



6.00 



28 



May 28 



9.30 



17 



6.00 



13 



June 10 



10.00 



20 



5.00 



39 



May 29 



9.30 



13 



8.30 



19 



June 11 



10.00 



26 



5.00 



27 



May 30 



9.30 



11 



6.30 



25 



June 12 



10.00 



41 



5.30 



22 



May 31 



10.00 



46 



8.30 



16 



June 13 



9.30 



8 



( 2 ) 



( 2 ) 



June 1 

 June 2 



10.00 

 9.30 

 10.00 



20 

 14 



13 



6.00 

 5.30 



( 2 ) 



15 

 42 



( 2 ) 













Total 





348 





421 



June 3 











1 All removed. 



2 No record. 



SEASONAL HISTORY. 



The data show that moths may emerge at any time during the 

 winter or early spring, and so far as known they may begin breeding 

 if suitable food plants are found. Cotton does not grow as a peren- 

 nial in this section. Sometimes it is left for the second year to pro- 

 duce a "zoca" crop, but the plants are dormant during the winter 

 and the crop is produced from sprouts sent out from the roots or 

 old stalks. Planting may begin during the first part of February, 

 but usually begins about the middle, depending upon the season. 

 Squares are not formed in any numbers until about the first of May, 

 usually a little earlier on the zoca than on the plant cotton. Holly- 

 hock, another host plant of pink bollworms, may be in bloom earlier 

 than cotton, but it is considered of no economic importance in this 

 connection. Repeated attempts to secure oviposition on young 



