THE AMERICAN ENTOMOLOGIST. 



and must always be taken ciiiii grana salis. 

 Yet, after making due allowance for possi- 

 ble error, the number of intelligent ])Ianters 

 whom I have conversed with, and who, 

 ha\ing long and thorough acquaintance 

 with the moth, feel positive of their ability 

 to distinguish it and of having seen it dur- 

 ing the winter, is so great as to leave little 

 doubt of the fact ; while the added testi- 

 mony of Prof. Grote, who is such authority 

 on moths that he could not thus confound 

 species, and who states that he has found 

 the Aletia in Alabama during mild winter 

 weather, should dispel even that little doubt ; 

 and we may safely consider as proven that 

 the moth does survive the winter up to 

 the end of March. The general experience 

 of correspondents is, however, that after 

 March these hibernating moths are no longer 

 to be seen, and no one knows what be- 

 comes of them between this time and the 

 appearance of the first worms. 



The difficulty felt in bridging this gap 

 together with the progress of injury from 

 the South northward have given rise to the 

 theory that the species cannot survive the 

 winter in this country, and must necessarily 

 come each year on the wing from some ex- 

 otic country where cotton is perennial. 

 Mr. Robert Chisolm of Beaufort, S. C. 

 seems to have been the first to suggest the 

 theory, but the first published statement of 

 it that I can find is by a Dr. Gorham who, 

 in ,1852, distinctly says:* "my speculations 

 on the nature and habits of the Cotton Fly 

 have led me to adopt the following hypoth- 

 esis : That it is a native of tropical cli- 

 mates, and never can pass a single winter 

 beyond them, consequently never can be- 

 come naturalized in the United States, or 

 any where else where the cotton plant is 

 not perennial." 



Two years later it was more fully set 

 forth by Dr. W. I. Burnett, f from facts 

 communicated by Mr. Chisolm, and lastly 

 it was again urged, as original, by Prof. 

 Grote in 1874.! Prof. Grote's conclusions 

 were " that it dies out every year (laith its 



♦DeBow's Industrial Resources of the Southern and West- 

 ern States 1852, p. i6g. 



t Proc, Bost. Soc. Nat. Hist. 1854, Vol. IV, pp. -116-17 

 X Proc. A. A. A. S., 1874, B- P- ;8. 



food plant', tliat it occurs in ilic cotton belt of 

 the Southern States, and that its next appear- 

 ance is the result of immigration. 



The principal arguments urged in sup- 

 port of the theory by Prof. Grote are ! i > 

 the sudden appearance of the moth in quan- 

 tities ; (2) the first appearance of the worms 

 so late as the latter part of June ; (3) the 

 absence of parasitic checks ; (4) the highly 

 probable exotic origin of the species and 

 introduction into the States ; and (5) the 

 ])ower of flight and migratory habits of the 

 moth. The first three lose much of their 

 force from the facts adduced in this bulletin, 

 since (i) in the Southern portion of the 

 belt the sudden appearance is more ap- 

 parent than real, '.2} the worms appear in 

 April, and (3) they have numerous para- 

 sitic checks. There is also little force in 

 the fact of original introduction from some 

 foreign country, since most of our worst 

 insect pests that are now acclimated and 

 established with us, were originally intro- 

 duced from abroad ; while (4) the migra- 

 tory habit, as we have seen, is not devel- 

 oped in the first moths. Arguments urged 

 by others in favor of the theory are (6) the 

 periodical visitations and intervals of im- 

 munity ; (7) the short life of the moth ; 

 and (8) the failure of those who have tried 

 to keep it through the winter. To these 

 it may be replied that (6) many other in- 

 digenous insects abound during certain 

 years and are unknown in others, and that 

 these changes are due to the working of 

 well known laws ; that periodicity oi Aletia 

 is largely imaginary, because it either refers 

 only to bad years and takes no stock of 

 small numbers, or else is local. The in- 

 vestigations of the Commission show that 

 the worm has been in some part of the 

 South every year since the civil war, and 

 there is no reason to suppose that it was not 

 annually to be found in fewer or larger 

 numbers prior thereto. 



(7) The short life of the moth of the 

 summer generations is no criterion for that 

 of the last or hibernating brood, since any 

 number of species which produce several 

 annual generations and have but a brief 

 span of life in the imago state in summer, 



