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plant, as well as those of the weeds which surrouucl the plantation. The eggs 

 are deposited principally on the under sides of the leaves, but often upon the 

 outer calyx ; and I have even found them, when very numerous, upon the stem 

 itself. 



Wherever these caterpillars were very abundant, I counted from ten to fifteen 

 eggs on a single leaf; they are very small, and difficult to be distinguished from 

 the leaves themselves, on account of their green color. In shape the eggs are 

 round and flat, and, when examined luider a microscope, they appear regularly 

 furrowed or ribbed. Their color, when freshly deposited, is of a beautiful semi- 

 transparent sea-green. They are closely attached to the leaf on which they are 

 laid. I am thus particular to state this, because, in an able article published 

 some time ago, it was alleged that " the egg is fixed upon the leaf by a small 

 filament attached by a glutinous substance." This mistake might the more 

 easily be made by any person Avho had not himself observed the eggs when 

 hatching, as that of the lace-wing fly is held by such a filament, and, moreover, 

 is found in similar situations on the leaves, but generally with or near a colony 

 of plant-lice, where the instinct of the parent lace-wing fly teaches it to deposit 

 its eggs, and thus provide for a supply of fresh food for the young larva?, which 

 feed upon and destroy millions of the cotton-lice. There is a great difference 

 also between the eggs of the caterpillar moth and those of the boll-worm moth, 

 the first being, as before stated, round and flattened in shape, and green in color, 

 whereas those of the boll-worm moth are not flat, but more of an ovoid shape, 

 and of a dirty-yellowish tinge. I cannot state exactly what time is required to 

 hatch the eggs after they have been laid by the parent fly, as I could not suc- 

 ceed in procuring- any from the moths hatched and kept in confinement, although 

 carefully preserved for the purpose. Dr. Capers says that it requires from four- 

 teen to twenty days ; but the eggs I founcl in the fields invariably hatched 

 within a week from the time they were brought into the house. However, this 

 must depend a great deal upon the state of the atmosphere and the warmth of 

 the season. The young caterpillars, when hatched, very soon commence 

 feeding upon the parenchyma, or soft, fleshy part of the leaves, and continue to 

 do so until they become sufliciently large and strong enough to eat the leaf 

 itself. They are able to suspend themselves by a silken thread when shaken 

 from the plant. They change their skine several times before attaining their 

 ful] growth, when they measure from one and a half to nearly two inches in 

 length. The first brood of caterpillars, in August and September, were all of a 

 green coloi', with narrow, longitudinal, light stripes along each side of their 

 bodies, and two broader, light-yellowish stripes along each side of their backs, 

 down the centre of each of Avhich was one distinct, narrow, light-colored line. 

 Each of the broader bands was marked with two black spots on each segment ; 

 and on each segment of the sides were three or more dark dots. The head was 

 yellowish-green, spotted with black. The caterpillars of the second and third 

 generations are of a much darker color than those of the first ; their under parts 

 are more of a yellowish-green, and their sides sometimes of a purple cast ; their 

 backs are black, with three distinct light-colored lines running down their 

 length ; and their heads are also darker, and of a yellowish-brown, spotted with 

 black. 



The question naturally arises. What causes this change of color in the latter 

 part of the season, since the moths hatched from the lightest and darkest cater- 

 pillars prove to be exactly the same 1 Several planters attribute it to the influ- 

 ence of the sun, or to the food upon which they subsist; but this can scarcely 

 be the case, as I have often observed individual caterpillars, evidently of the 

 second or third generation, of the lightest green color, among a crowd of the 

 black worms on the same leaf, as late as October, and exposed to the same in- 

 fluences of the sun. 



These insects appear to multiply to the greatest extent in damp, cloudy 



