THE BOLL WORM — CHARACTERS AND TRANSFORMATIONS. 369 



There were hundreds of the pnpte devoured by some enemy that broke into the larger 

 end. Much of this work was freshly done ; and when we first observed it, a few days 

 previously, I was disposed to attribute it to a small black or dark-brown grub (sup- 

 posed to be a Telephorus), many of which I found in the newly-rifled chrysalids, de- 

 vouring the remains. But these were never in sufficient numbers to account for the 

 destruction of the Aletiae. Professor Jones on the occasion alluded to caught a boll- 

 worm in the very act ; and I have since verified their propensity by finding them to 

 prefer this diet to every other. Further observation, therefore, led me to acquit the 

 little Telephorids of initiatiug the robbery. They only play the jackal at this feast ; 

 the lion they follow is the boll-worm. 



Dr. Anderson, in one of his letters, says : "Accompanying this I send 

 a larva (Heliothis armigera) found preying upon Aletia larva in its web, 

 and this has been so often repeated as to induce me to think it may be 

 classed among those destructive to Aletia." 



This habit was also observed by Mr. Hubbard in Florida and by Mr. 

 Schwarz in Alabama. The latter states that it was more often the 

 strongly marked, highly striped individuals which were found preying 

 upon the Aletia pupae than any other variety. 



Ko instance, so far as we are aware, have been noticed or recorded 

 where the Boll Worm has been found feeding upon Aletia larvae when 

 free upon the plant ; but in the breeding-cages it will eat almost anything 

 in the shape of a Lepidopterous larva, no matter how much vegetable 

 food may be supplied to it. An interesting instance of this came under 

 our notice in 1882, in the case of a larva of Heliothis found feeding 

 upon tomato leaves, which, when placed in a breeding-cage with larvae 

 of Plusia brassiecBj found upon the same plant, not only destroyed the 

 Plusia larvae in preference to feeding upon the fresh tomato leaves 

 furnished to it, but even penetrated a newly spun cocoon and devoured 

 a larva which was filled with specimens of Copidosoma truncatellum^ 

 parasites and all. 



The length of life of the larva of Heliothis varies of course with the 

 season of the year, and also with the state of the weather. According to 

 Dr. G. W. Smith-Yaniz, of Canton, Miss., who has reared the worm 

 from the egg state, it occupies from e^gg to pupa, in the month of Au- 

 gust, twenty-one days. Prof. E. W. Jones, without further qualification, 

 places it at from fifteen to twenty days, and Judge W. J. Jones states 

 that the early brood in corn spends three weeks in the larva state. 

 The only detailed statement of the growth of the worm yet published is 

 the following, taken from Glover (1866) : 



A Boll Worm which was bred from an egg found upon the involucre or '^ ruffle " of 

 a flower-bud grew to rather more than a twentieth of an inch in length by the third 

 day, when it shed its skin, having eaten in the mean time nothing but the paren- 

 chyma or tender fleshy substance from the outside of the calyx. On the fifth day it 

 pierced through the outer calyx and commenced feeding ins-ide. On the sixth day it 

 o.gain shed its skin, and had increased to about the tenth of an inch in length. On 

 the tenth day it again shed its skin, ate the interior of the young flower-bud, and had 

 ^rown much larger. On the fourteenth day for the fourth time it shed its skin, at- 

 63 CONG 24 



