INFLUENCE OF WINDS ON ALETIA. 85 



for the worms seldom, if ever, die from excessive heat in this country, 

 except as they fall upon the heated surface of the ground. 



The indirect influences of wet weather, first pointed out by the writer in 

 July, 1 879, in some remarks before the Mobile Cotton Exchange,* are even 

 more potent in favoring the development of the worms. They consist 

 in the comparative immunity which the pest enjoys during such weather 

 from its numerous natural enemies, presently to be mentioned, all of 

 which are prevented during wet weather from working with the energy 

 and activity they display during dry weather. This holds especially 

 ' true of birds and ants, the latter of which not only hie to their nests 

 during such weather, but are often drowned in countless numbers in 

 open fields during heavy showers. Few who have not carefully ob- 

 served the facts can appreciate the results of the non-working, even for 

 a few short days, of these natural checks to a species so remarkably 

 prolific and quick of growth as our Aletia.^ 



It may also be remarked in this connection that wet weather is un- 

 favorable to the poisoning of the worms, and prevents the working of 

 cotton, which working, as will be shown further on, also helps to destroy 

 them. 



Such are our conclusions and the reasons therefor. One of our cor- 

 respondents has, however, made the statement that in his locality a dry 

 season may be followed by worms, while a wet season may not ; and he 

 is inclined to lay great stress upon the effects of east and southeast 

 winds in bringing the worms. We quote herewith one of his letters 

 which we formerly published in the American Entomologist, Vol. Ill, 

 pp. 105-106 (April, 1880) : 



Influence of winds on alexia. — I discover yonr leaning towards the theory that 

 in this latitude the Aletia hibernates, and that the advent of it on the summer's cotton 

 growth is fi*om the hibernated moth of the vicinage. 



I have heretofore expressed both to yourself and to Professor Comstock the result 

 of my observations, to the effect that a dry season — that is, one not too wet for cotton — 

 may be followed by the caterpillar, in this latitude, in such numbers as to do great 

 injury to the crop; and that a wet season — that ia, one in which the rainfall lessens 

 the maturity of the fruit — ^may not be followed by the caterpillar in sufficient numbers 

 to injure the crop, 



I desire to direct afresh your observation to the influence of the winds on the Aletia. 

 For some years past this has been my own observation on that subject, viz : 



(1) At any season of the year the prevalence of southeast winds for two or three days 

 consecutively, regardless of wet or dry weather, will be followed in fifteen to twenty 

 days after the prevalence stated of those winds by the moth of the Aletia in large 

 numbers. 



(2) K the winds prevail from any other course than east and south of east, after 

 May and until October, we do not, in this latitude, find the caterpillar in numbers 

 sufficient to injure the crop of cotton. 



(3) Last year ( 1879) I made note of the following facts : The month of May was dry in 

 this vicinity ; so dry that corn was retarded in growth, and everywhere unpromising; 

 east and southeast winds prevailed ; ergo (?) early in June the cotton caterpillar was re- 

 ported in large numbers in Montgomery and Dallas Counties ! 



* Mobile Kegister, July 9, 1879. 



