ENTOMOLOGIST AND BOTANIST. 



363 



THE FAIL ARMY -WORM. 



Prodeaia autumnalu, n. sp. 



rt white ; (h) dark 



We herewith present figures of the moth of 

 the Fall Army-wonn, of which worm we gave 

 a brief account in the last number, and wMch 

 has attracted such general attention this fall in 

 many parts of Kansas, Illinois and Missouri. 

 We have already shown how easily this worm 

 may be distinguished from the true Army- worm, 

 to which it bears a slight resemblance ; and, by 

 comparing the above Figure 221, a, with that of 

 the true Army-worm moth (Fig. 223) the two 

 insects will be found to dilfer still more widely 

 in the perfect state. 



Our Fall Army-worm moth is a most variable 

 one — so variable, indeed, that at least three 

 species might easily be fabricated by any species- 

 grinder who happened to capture at large the 

 three most distinct varieties, without knowing 

 anything of their transformations. We have 

 bred 31 specimens, all from larvae found on corn, 

 and have others which were captured at large, 

 and though half a dozen sufficiently distinct 

 varieties might easily be picked out from among 

 them, and though scarcely any two are precisely 

 alike, yet they may all be divided into three 

 distinct sets or varieties. The first of these, 

 which is the more common, is represented at 

 Figure 221, a, the second at b, and the third at 

 c. For those who are more curious in such 

 matters we appeud, at the end of this article, a 

 more elaborate description of this new moth. 

 Not only do we find this great variation in this 

 particular species, but all the species of the 

 genus to which it belongs are variable ; and 

 Guen6e has truly remarked that they resemble 

 each other so closely, and their modifications are 

 so complicated, that it is next to impossible to 

 properly separate them. We have in this coun- 

 try a very common moth (Prodenia commelincB, 

 Abb.) which may be popularly called the Spider- 



wort Owlet moth, some of the varieties of which 

 approach so nearly to some of the more strongly 

 marked varieties of our Fall Army-worm moth 

 that it is necessary to show the very great dif- 

 ference which really exists between them, in 

 order that the cultivator may not be unneces- 

 sarily alarmed when he observes the former, by 

 confounding it with the latter, and erroneously 

 inferring that he will be overrun with Fall 

 Array-worms when there is no real danger. The 

 [Fig. 222] Spiderwort Owl- 



et moth, which 

 ^v«^"W ^^'*' herewith il- 

 ''f/-^"^S\ ) ^ hiMrate (Fig.222) 

 is a handsomer 

 and more dis- 

 tinctly marked 

 species, the front 

 wings inclining 

 more to vinous- 

 gray, orpurplish- 

 trray, and the or- 

 dinary lines being 

 more clearly de- 

 colors— (a) vinouB-brown, vclvety-btack and fined by Very 

 yellow; (i and cjeray, deep brown, while Olid _ , ., 



fulvous. deep brown , than 



in the Fall Army-worm moth. But, however 

 much these characters may vary — and they are 

 quite variable — there are yet two others which 

 will be readily noticed upon comparing the 

 figures of the two species, and by which the 

 Spiderwort moth may always be distinguished 

 from its close ally, namely, by the tip of the 

 wing being more prolonged and acuminate, 

 and by the three-forked nerve in the middle of 

 the wing being mucli more conspicuous. Its 

 larva never congregates in multitudes as does 

 the Fall Army-worm, and dificrs so materially 

 from that worm, and is withal so characteris- 

 tically marked, that it may be recognized at once 

 by our illustration (Fig.222,r?). Contrary to what 

 its name would indicate it is a very general 

 feeder, as we have found it on all sorts of succu- 

 lent plants, both wild and cultivated. This 

 insect is more or less numerous every year, but 

 has never been known to multiply so prodigi- 

 ously as the Fall Army-worm, which we have 

 under consideration. 



Now that we have sufficiently dwelt on the 

 characteristics of the Fall Army-worm to enable 

 any one to distinguish it, even from its nearest 

 relative, let us consider for a moment what can 

 be done to prevent its great injuries to grains 

 and to vegetables. We have proved that there 

 are at least two, and probably as many as three 

 or even four, broods during the course of the 

 year; for those worms which appeared in such 



