75 



squares within, ranging from 2 to 5 at various times. In making the 

 daily observations the cage was entered and every square examined. 

 Each square found attacked in any way was marked with a numbered 

 tag containing full data as to the lot of weevils and the number pres- 

 ent, date, and nature of injury. After all weevils had been found 

 the cages were removed to new uninfested plants for another day's 

 work. Close watch was kept upon all tagged squares upon succeed- 

 ing daj T s, and every important change taking place in each square 

 was added to the record on the tag. The additional special points 

 noted in each case, so far as was possible, were: The formation of 

 a distinct wart; time of flaring, yellowing, and falling; the emer- 

 gence of adult; presence of a parasite; death of larva, pupa, etc. A 

 very complete history of each square was thus obtained. During 

 the season of 1903 three special periods were selected for study of this 

 kind. The first was taken during the earty part of June, when hiber- 

 nated weevils only were active, the second was taken in August for 

 the work in midsummer, and the third in the latter part of October 

 for the stud}^ of the development of late weevils. Altogether in these 

 three series over a thousand squares were tagged and recorded. The 

 work of males was compared with that of females in this way, as were 

 also the developmental periods in squares and bolls. Nearly 1,500 

 more of these records were obtained in the work of 1901. Although 

 requiring a great deal of, time and close attention, the numerous defi- 

 nite observations obtained abundantly justified the work required. 



FEMINIZATION. 

 AGE OF BEGINNING COPULATION. 



After the adult weevils have left the squares a certain period of 

 feeding is necessary before they arrive at full sexual maturity. This 

 period varies in length according to the effective temperature prevail- 

 ing, and appears to bear about the same ratio to the developmental 

 period as does the pupal stage. 



Among the man}^ weevils kept from emergence till death for the 

 purpose of ascertaining the length of life without food, copulation 

 was never observed. With weevils fed upon leaves alone the period 

 preceding copulation is about twice the normal length, in the cases 

 observed, of those having squares to feed upon. 



During the hot weather this period appears to be on the average 

 only about three or four days in length, while as the weather becomes 

 colder it increases gradually until weevils may become adult, feed for 

 a time, and go into hibernation without having mated. 



