NOTES. [101] 



with the points extending beyond it, but Avliicli in action bend back at right angles 

 therefrom. (See also Note 23.) 



Note 9 (p. 10). — See the article, Nectar : what it is and some of its uses, by William 

 Trelease, published in the Eeport upon Cotton Insects, Department of Agriculture^ 

 1879, pp. 319-343. In this article the author discusses especially the extra-florai 

 nectar glands of the cotton plant and their relation to Aletia. Ho concludes that the 

 glands of the cotton plant seem to have been produced to secure the protection of the 

 leaves and flowers of the plant from leaf and petal eating insects, like ants, but at the 

 same time, since the introduction of the Cotton Worm, the glands have become inju- 

 rious to the plant by attracting the moths at night, which alternately sip nectar and 

 oviposit upon the leaves. The tendency now would naturally be to remove the glands 

 by natural selection, but this is opposed by the methodical selection of man, who in his 

 desire to produce a good staple and a vigorous growth pays no attention to the power 

 for secreting nectar, and as this function does not cause any drain on the energy of 

 the plant, it stands no chance of being removed. 



Note 10 (p. 12). — Eeferring to the extreme rapidity with which the broods follow 

 one another in midsummer, we made use of the following paragraph in our address 

 before the Atlanta Cotton Convention, November 4, 1881 (see Bibliographical list) : 



*'The first worms appear much earlier than was formerly supposed, viz., from the 

 middle of April till the middle of May, in the southern portion of the cotton belt. 

 The fact that these early worms generally attract no attention, and that the species 

 seldom acquires disastrous force till the third generation, has given rise to the erro- 

 neous notion of later first appearance. There are also many more generations than 

 has been supposed, seven or more being produced toward the Gulf, the last enduring 

 till frost cuts it off. When I tell you that in addition to this rapid succession of 

 broods the moth is one of the most prolific with which I am acquainted, capable, 

 in fact, under favorable circumstances, of laying six or seven hundred eggs, you will 

 no longer wonder at its destructive capacity. The progeny of a single female may, 

 in less than two months, under the influence of midsummer temperature, reach 

 twenty billions, while you all know that half a dozen worms to a plant are sufficient 

 to jeopardize the crop. Why, were it not for the various natural checks upon the 

 increase of the species in geometrical ratio, successful cotton-culture, with all our im- 

 proved methods for destroying the pest, would be utterly impossible. Remove the 

 barriers and the flood comes. The occasional impotence of the natural checks, through 

 one cause or another, very quickly gives the Cotton Worm the mastery in the struggle 

 for existence, and precipitates it upon us in multitudes almost as if by magic." 



Note 11 (p. 12). — This is well illustrated by a fact communicated by Dr. D. L. 

 Phares, of Woodville, Miss., viz., that the worm usually begins its work of destruc- 

 tion in Madison County from three to six weeks earlier than in Wilkinson ; the former 

 on latitude 33°, and the latter resting on 31°. At Madison station, in the southern 

 part of Madison County, the thermometer marked the extreme low temperature of — 4° 

 F. during the winter of 1878-79, while at Woodville, only about two degrees farther 

 south, the lowest temperature noted was 14° F., or a difference of 18°. 



Note 12 (p. 12). — In this connection we quote the following note on hibernation 

 from the American Naturalist for April, 1883. It is a brief abstract of a paper read by us 

 before the American Association for the Advancement of Science at the Montreal 

 meeting in 1882 : 



"The Hibernation of Aletia xylina. Say, in the United States a settled 

 FACT. — I have already shown in previous remarks before the association that there 

 were various theories held by competent men — both entomologists and planters — as 

 to the hibernation of this Aletia (the common Cotton- Worm of the South) ; some be- 

 lieving that it hibernated in the chrysalis state, some that it survived in the moth 

 state, while still others contended that it did not hibernate at all in the United States. 

 I have always contended that the moth survived within the limits of the United 



