93 



From this it is apparent that the first generation is distinguished by 

 its much shorter life, but with regard to any other generation it is not 

 safe to generalize, except possibly to mention that the longest indi- 

 vidual records were made during the month of September. 



During September Mr. Girault experimented on a series of twenty 

 moths, each of which was subjected to diiferent conditions of food 

 supply. His results are given below. 



Table XXXVII. — Effect of food conditions on length of life of moths. 





Number and sex of 

 moths. 



Food given. 



■ 



Length of life. 



Range. 



Eggs de- 

 posited. 



Lot. 



Males. 



Females. 



Gerieral 

 average. 



1 



1 female, 3 males 



None 



Bays. 

 6 



Bays. 



H 

 H 

 lOi 

 30 



Bays. 



H 



6i 



Vf 



10 



23f 



Bays. 

 3 to 6| 

 4ito 9i 

 6ito 8i 

 7 tol2i 

 17 to 38 



23 



2 





91 



3 

 4 

 5 



2 males, 2 females 



2 males, 2 females 



2 males, 2 females 



Sirup one day 



Water everj^ day . . 

 Sirup every day . . . 



6i 



in 



160 



10 



866 



It is at once seen that the length of life increases as we pass down 

 the columns, but that oviposition is not really begun until food is 

 obtained, for it will be noticed that moths given only water laid prac- 

 tically no eggs, although they lived longer than those fed once on 

 sirup. This one feeding, however, sufficed to induce considerable 

 oviposition. 



The apparent necessity for a continuous food supply is a factor 

 which is very important in relation to the feeding habits of the moths 

 in nature, and will be referred to again in connection with the use of 

 June corn and cowpeas as a trap crop. 



One point which may be mentioned in passing is the gluttony of the 

 moths when given abundant food. The sirup or sugar solution used 

 in the laboratory had to be given very sparingly, otherwise the moths 

 would gorge themselves, and the subsequent fermentation of the sugar 

 which could not be digested would invariably cause premature death. 



DAY HABITS. 



During the daytime the boUworm moth is usuall}^ yery quiet, rest- 

 ing immovable in more or less concealed places. During the early 

 part of the summer, corn, which is still in the "bud," furnishes the 

 favorite hiding place. Here the moths remain well down in the cen- 

 tral cavity or between the still closely curled leaves. The insects rest 

 with the head up and the wings tightly folded down over the back. In 

 this position they often remain during the entire day unless molested 

 or frightened. A jarring of the plant, or any unusual disturbance, 

 however, quickly awakens the resting moth, apd hastily leaving 'the 

 plant it flies wildl}^ until it chances upon another, where it quickly 

 insinuates itself into the bud by a series of zigzag backward move- 



