APPENDIX I REPORTS OF OBSERVERS. 353 



it lives and moves and has its being were in full operation here. It appeared .13 

 early as July in a few fields, and, passing through three generations, left not a leal' 

 behind. In others, it appeared later, doing less damage, but leaving no vegetation. 

 In others, later still, doing but slight damage, but eating and destroying until arrested 

 in its course by frost. In other cases it appeared early, doing no noticeable damage. 

 It was preceded by our grass-worm, which I have only observed in the early summer 

 or spring, and of which 1 have never seen two broods in one season, and which never 

 proves damaging to cotton, though it will to a limited extent cut it down when young 

 and eat the leaves of older cotton. This grass-worm and Aletia are often confounded, 

 and some of our most intelligent planters insist that Aletia is the progeny of the grass- 

 worm, and they base their belief upon the fact that where you find the grass-worm 

 early in the season, in from twenty to thirty days you are sure to lind Aletia. They 

 think the difference in appearance is owing to an advance in the season. A compari- 

 son of the insects and their different modes of pupation settles this question conclu- 

 sively. Aletia, with its bright stripes, yellow head spotted with black, its false ven- 

 tral feet, consequent looping gait, with each of its sixteen sections having sixteen 

 black spots or tubercles, from which a hair or bristle projects, and its general business- 

 like carriage, once known, cannot be mistaken for any other. 



The first cotton-worms were observed here last season about the 20th July, in a field 

 of about 25 acres and in the lowest spot, the first generation destroying about 3 acres 

 of cotton. There were none to be found there in any other field, and none nearer than 

 30 miles south, near Canton. This 25-acre field was isolated and surrounded by forest. 



Did the moth come by migration or was it bred there f June and July had been 

 characterized by frequent rains ; but from the first appearance of the worms the 

 showers were becoming occasional, and nothing indicated the arrival of the miller or 

 moth. From the first to the last of August, while showers were occasional, the worm 

 continued to appear in different fields ; in the older fields first, in the newer and 

 fresher later. 



MIGRATIONS. 



This might be accounted for by short migrations of the moth, but more naturally 

 from its being indigenous. That the worm appears in different latitudes, earlier south 

 and later north, as thermal temperature increases, there is no doubt; and under this 

 law of development it reaches its ultimate northern limit last. Close observations of 

 the moth and worm furnish no indications of a migratory tendency. The moth se- 

 cretes itself by day, and at night confines its flight to a limited area ; and instead of 

 spreading or depositing its egga over a large area, seems to concentrate them, and oc- 

 cupies just as much as will be eaten by each generation and no more. The worm 

 seems averse also to migrate ; and, as has been noticed by others and myself, will eat 

 up to a line and will not cross it, and, it has been asserted, will not eat other cotton 

 if placed upon it. Where they have stripped a field I have seen them wandering in 

 the grass, on fence-rails, and the sward on the outside of a field, looking, probably, for 

 food or to pupate. The migratory theory is doubtless based upon the supposition that 

 the insect does not hibernate in any form in this latitude, and even two degrees south 

 of this. Upon this point observers differ ; and it is not only an interesting question 

 entomologically, but one of vital interest to this commission, as its objects cannot be 

 successfully accomplished until we arrive at something like certainty as to the history 

 of the insect. 



For twenty years past I have been a casual observer of the cotton-worm, and, as far 

 as my memory serves me, recollect it as an annual visitor, often in such small numbers 

 as to attract no attention, but occasionally to have proved very damaging. My atten- 

 tion was first arrested by a phenomenal mode of generation, of which I could get no 

 explanation from my more experienced planting friends, I therefore took the subject 

 into mature consideration. In this case, the eggs of the moth, though no moth had 

 been seen, had been deposited on the cotton and were there hatched, the larva destroy- 

 ing all the leaves and young bolls along fifteen or twenty furrows, but did not touch 

 the adjoining rows on either side. This was in July, 1858. They passed into chrysalids 

 on the stalks and then disappeared, no other cotton being visited that season. I have 

 frequently since seen them appear in the same mysterious way, and have verified my 

 predictions as to their appearance at a particular time and place. 



THE EGG. 



Regarding, as I do, the insect as indigenous and the chief function of the moths to 

 be reproduction, the eggs would be speedily laid, after copulation, upon the cotton-leaf, 

 awaiting the natural process of development. This, under favoring atmospheric con- 

 ditions, proceeds annually, to a limited extent, under solar evaporation. This theory 

 may be exemplified by a topographical feature, which has been strongly emphasized 

 by some observers, and offers a solution of what might otherwise be unaccountable. 

 Parts of a field often escape and seem to be avoided by the worm, while adjoining cot- 

 tou may be totally eaten out. This is notably the case on the eastern side of fields, 

 but may occur at any shaded point. I noticed a field, this season, where the worm had 

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