THE COTTON CATERPILLAR. 215 
the third brood. Each female moth is said to lay at least five hun- 
dred eggs, so any one can judge how rapid is the increase. 
Thus the caterpillars keep on multiplying into new broods till 
near the middle of November, when the frost kills them off.. The 
common belief among the negroes is that the caterpillar knows 
when the frost is coming, and takes to the woods, where it sleeps 
till the next spring, but I have never verified their belief. “As the 
cotton plant gets older and the leaves tougher, the caterpillar in- 
creases in size and activity and eats from morning till night. Of 
course, as the plant loses its leaves, it dries up and the fruit bolls 
wither and rot, just as apples do under similar conditions. After 
the worms have taken possession of the fields, it is always esti- 
mated that from one-half to three-fourths of the yield has been cut 
off. We have this year about three hundred acres planted in cot- 
ton. At the lowest calculation of price and yield per acre, this 
ought to turn us in a $16,000 crop; butif the eer get into 
it, we shall be lucky to get $8,000 out of it. 
As to where or how the cotton caterpillar originated, several the- 
ories have been advanced. Some say that they came from the Ba- 
hama islands to Florida and thence spread up along the coast.* 
But I suppose they came just as the canker and currant worms 
came, and it is as easy to account for one as the other. Their devel- 
opment depends much on the state of the atmosphere. Dog-day 
weather seems to be favorable to their increase and spread, while 
a hot sun scorches them and renders their food, the leaves, dry 
and tough. Before the war, they did not appear oftener than once 
in seven years, and many old and experienced planters say that 
we have them now oftener, because our method of cultivation is 
different from theirs and not so thorough. It was always cus- 
tomary to burn off all the cotton fields and old pastures after the 
frost had killed vegetation, thus destroying any eggs that might 
have remained unhatched. This practice in many cases ‘is neg- 
lected now; and again they say that we put off ploughing up our 
ground too late ; that by ploughing early, the frost has a chance to 
act on the soil ‘i kill all grubs and eggs deposited under the 
surface. The darkey also has his reason, which perhaps is as good 
as any yet assigned. He says the guano brings the caterpillar, 
reasoning from the fact that it always attacks the rankest cotton | 
*For an account of the distribution of the army or cotton worm, see the NATU- 
RALIST, Vol. iy, p. 52. 
