34 BULLETIN 231, U. S. DEPARTMENT OF AGRICULTURE. 



the bolls yielded a total of 84 live weevils; one containing 3, 5 others 

 containing 2 each, and the remainder containing 1 each. One boll 

 had been completely eaten out by a bollworm, and another showed 

 signs of weevil injury and a braconid parasite cocoon. Two dead 

 pupae and 2 dead larvae were found in 4 other bolls. Their 

 deaths were in all probability due to climatic causes. The remaining 

 boll contained signs of weevil larval work, but no insects, either 

 dead or alive, were found. One boll which contained a weevil adult 

 also contained a tiny, light-green lepidopterous larva. 



Of the 84 weevils found in the bolls, 52 were males and 32 were 

 females. One additional male was found crawling among the 

 bolls when the bag was opened. Those in the bolls were all tightly 

 sealed in the pupal cells and were usually quiet when first opened. 

 As soon as the weevils were exposed to the air they became quite 

 active and remained that way. 



The peculiar feeding habit of the larvae of these weevils is certainly 

 well adapted to destroying the maximum number of seeds in a 

 boll. They do practically all their feeding in the center of the 

 boll and form the pupal cells in this same place. Owing to the 

 arrangement of the seeds this location of the larva enables it to 

 injure practically every seed in the boll instead of injuring those 

 of one lock as is usual with the cotton weevils. 



On March 12, 1914, another lot of infested Thurberia bolls were 

 examined. These were collected by Mr. Schwarz in a small canyon 

 between Stone Cabin and Sawmill Canyons, Santa Rita Mountains, 

 Ariz., on December 7, 1913, at about 3,900 feet altitude. The bolls 

 were sent to Washington soon after collection and had been in a 

 cool cellar from that time until examined. 



Examination of 39 of the bolls showed 2 clean and the remainder 

 infested. Thirty-three bolls yielded 36 live weevils, 3 bolls contain- 

 ing 2 each. Three dead adults (2 females and 1 male) were found 

 in as many bolls. These deaths were probably due to climatic causes. 

 One boll was found which showed signs of larval injury but the larva 

 was not to be found. No signs of parasitism were found. One 

 lepidopterous larva like the one noted in the preceding lot was found 

 in a boll with a weevil. The live weevils consisted of 18 males and 

 18 females. 



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