COTTON BOLL WEEVIL IN THE MISSISSIPPI VALLEY. 9 



During 1915 a number of okra plants were examined for weevils 

 with the following results: On September 10 a few plants were 

 examined at Inverness, Miss. Three open blooms were found and 

 five boll weevils were in them, one blossom containing three. On 

 September 29 and 30 a total of 122 okra plants were examined between 

 Tallulah and Mound, La. These plants had 114 open blooms but 

 the only weevil found was on the fruit. This individual was watched 

 for about five minutes and in this time it made no attempt to feed. 



Several additional records of the weevil on okra were made during 

 the season on the plants growing at the laboratory and also in the 

 field. Nearly all of these weevils were in the blooms and, where 

 feeding was found, it was confined to the petals and stamens. No 

 evidence of breeding in the buds or fruit in nature was secured. 



Laboratory studies were also made upon the feeding in captivity 

 and the possibility of breeding in the buds or fruit of okra. Sixty- 

 nine pairs of weevils were mated on okra buds and small fruit and 

 given only this food until death. Eleven eggs were deposited nor- 

 mally and three externally, but the larvse failed to survive on this 

 food. The weevils fed quite freely on J these foods and also on okra 

 blooms. In fact, the greatest amount of feeding was on the immature 

 boll at the base of the bloom. Occasionally this small boll would be 

 riddled with feeding punctures. 



One cage test was conducted in the attempt to produce somewhat 

 the conditions which would exist if cotton planting were suddenly 

 stopped and only okra left for food. For this purpose a large cage 

 was erected in the laboratory yard over a row of growing cotton 

 plants and a row of okra (fig. 2). On August 27, 100 weevils, 50 

 males and 50 females, collected from cotton in the field were placed 

 hi the cage. Daily observations on the relative number of weevils on 

 cotton and okra were made for 10 days. During this time 294 obser- 

 vations were made of weevils on cotton, while they were found on 

 the okra only 16 times. 



On September 6 the cotton plants were carefully removed from the 

 cage and only the growing okra left for the weevils. On September 

 7 six weevils were feeding on the okra and on September 8 seven 

 weevils were located, one feeding on a leaf and three feeding on the 

 bloom. On September 9 three examinations were made and from 

 3 to 6 weevils, one of which was feeding on a bloom, were found on 

 the okra each time. After that date the weevils were found on the 

 okra only at irregular intervals and on September 19 no live weevils 

 were found in the cage. At this time all the okra fruit was closely 

 examined for egg punctures but none were found. However, to make 

 sure that none were overlooked, all the fruit was placed on moist sand 

 in a breeding cage and saved for some time, after which the contents 

 were examined but no signs of larval work were found. 

 23922°— Bull. 358—16 2 



