81 



observed by Mr. E. A. Schwarz in tlie winter of 1901-2, weevils may 

 pass the winter in either larval, pupal, or adult stages, but the last 

 named is by far the most common stage. 



It is likely that a large part of the weevils found in the squares and 

 bolls during the first part of the winter will be in the larval stage, 

 while, owing to the slow development which takes place, a larger per- 

 centage of adults will be found toward spring. Mr. J. D. Mitchell, 

 of Victoria, Tex., took a number of live larva?, pupa', and adults from 

 bolls in a field in that locality on December 2G, 1903, after "two hard 

 frosts and one freeze." Two weeks later, from a field at the same 

 locality, after three hard frosts and two freezes, he took another lot 

 of live specimens in these three stages. In the latter case the bolls 

 examined were on stalks which had been plowed out two weeks before 

 and were ready for burning at the lime examined, Mr. Mitchell, who 

 is an excellent and reliable observer, writes: "On December 20, there 

 was still some sap in the cotton stalks," and on January 10, when the 

 second examination was made, " there was absolutely none." "The 

 larvfB seem to thrive and arrive at perfection in the dead and dried 

 bolls. A frost or freeze at 30° F. does not hurt the larva? or pupje in 

 dead bolls in the field. " As the two lots, taken together with four others 

 sent January 17, 31, and February 7 and 14, 1904, include 197 specimens 

 (231arvse, 30 puj)a?, and 144 adults) it is evident that large numbers of 

 weevils go into the winter in the immature stages, and there is every 

 probability that, in the southern part of the State at least, many of 

 them live and mature, emerging in the spring. It may be that this 

 gradual maturity of the hibernated weevils is one of the reasons why 

 they emerge so irregularly from their winter quarters. Not all wee- 

 vils go into hibernation at the same time, but as the mean average 

 temperature falls to between 55° and 60° F. they gradually cease feed- 

 ing, and, numbed and sluggish, they crawl into almost any place 

 which furnishes them some measure of protection from the cold. 

 Hibernating weevils are therefore to be found in many situations in 

 the field. Where the cotton stalks are allowed to stand throughout 

 the winter they furnish the weevils both the means of subsistence late 

 in the fall and an abundance of favorable hibernation places through- 

 out the field. The prospects of successful hibernation are thereby 

 multiplied many times; and, furthermore, the weevils are already 

 distributed over the field when they first become active in the spring. 

 The grass and weeds which almost invariably abound along fence lines 

 are exceedingly favorable to the successful hibernation of many wee- 

 vils, so that it will be found generally true that the worst line of 

 infestation in the spring proceeds from the outer edges of the field 

 inward. Where cotton and corn are grown in adjacent fields, or 

 where, as is sometimes the case, the two are more or less mixed in 

 the same field, many weevils find favorable shelter in the husks and 

 stalks of the corn. An especially favored place is said to be' in the 

 21739— No. 45—04 6 



