THE AMERICAN ENTOMOLOGIST. 



43 



sire she has examined the mixed lot, and in- 

 forms us that she can detect no diflerence of 

 any consequence among them. It is very true 

 tliat this does not amount to a definitive proof 

 that the Corn-worm sometimes feeds on unde- 

 veloped corn-tassels as well as on peas; but we 

 liave such confidence in Mrs. Treat's perceptive 

 powers as an entomological observer, that we 

 consider it as morally certain that the Corn- 

 woini docs so feed. 



The fact that the early brood of larvas, feeding 

 upon green peas and apparently also upon imde- 

 veloped corn-tassels, always has the longitudinal 

 stripes so obscurely represented, that in Mrs. 

 Treat's eyes they seemed to be of a uniform 

 green or brown color, is especially interesting 

 and remarkable. Several other such cases are 

 known to entomologists, where one brood of a 

 two-brooded insect ditfers constantly in color- 

 ation from the other brood; and philosophic- 

 ally such observations as these are of the very 

 highest importance, as throwing light upon 

 that mysterious question of the Origin of Spe- 

 cies, which is now puzzling so many brains. 



It has always been said by entomologists that 

 the Corn-worm or Boll-worm is two-brooded; 

 and in Georgia, according to Mr. Glover, even 

 three-brooded; and moreover we all know that 

 it cannot feed upon hard corn, but only upon 

 such as is in a soft or milky state. Since in our 

 hot summers the (j^rs of corn are developed and 

 matured with most surprising rapidity in the 

 northern States, it always seemed a mystery to 

 us, how two successive broods of the same 

 Owlet-moth could be matured there from green 

 com in one and the same season. We can now 

 better understand how the corn plant can in 

 northerly regions mature in one summer two 

 broods of corn-worms, and in southerly regions 

 even three ; for it would seem that the first 

 brood occasionally feeds upon the green tassel 

 or male flower, and the next broods upon the 

 ear and its silk, which is the female flower. 

 This point is elaborated more fully in the fol- 

 lowing extract from a letter of Mrs. Treat's to 

 us, dated iiugust 25th, 1869, or four days after 

 the publication of her Address on Insects: 



I did not think that this green larva, that eats 

 into the peas and the stalks of corn before the 

 latter are half grown, was, as you inform me, 

 this same striped boll-worm, that eats into the 

 soft ears of corn. I never found one of these 

 pea-eating, stalk-eating fellows striped ofl' like 

 the one that eats into the ears of corn. The 

 other day I passed through a large field of corn, 

 where the depredations of this worm were vis- 

 ible upon almost every stalk. They had done 

 the work weeks before, eating through the 

 leaves while they were folded around the stam- 



inate flowers, before the ears had begun to 

 make their appearance. So I suppose this sec- 

 ond brood was just then read}' to take the ears. 

 At any rate it is difficult to find an ear free from 

 their depredations. I have several chrysalids 

 of this last crop, and noticed that they looked 

 precisely like those of the first, although the 

 caterpillars were marked so difterently. This 

 last brood confines its diet more strictly to corn 

 than the first did, which ate into the stalks and 

 flower-buds of the Gladiolus as well as other 

 things; and when confined they would leave 

 the Gladiolus stalks for r-ipe tomatoes which 

 they specially liked. 



It was formerly supposed that there was but 

 a single larva that burrowed in the young stem 

 of corn, namely the notorious Spindle-worm 

 {Gortynazew, Harris). "We know now that, 

 at a somewhat later period perhaps in the 

 growth of the corn-plant, the Stalk Borer often 

 bores into the stem of the same corn-plant. 

 And it results from Mrs. Treat's valuable obser- 

 vations, that the first brood of the common Corn- 

 worm most probably does the same, or very near- 

 ly the same thing. AVe have also on hand an un- 

 described species of Owlet-moth {Prodeniu 

 near commelincv, Sm. Abb.), the striped larva 

 of which is of nearly the same size and general 

 appearance as that of the Corn-worm, and 

 eats into the heart of the young corn-plant in 

 Central Illinois, besides feeding externally on 

 the leaves. Of this larva we received very nu- 

 merous specimens from Mr. E. Daggy, of Tus- 

 cola, 111., in July, 18G8, with a full account of 

 its habits, and the moths made their appearance 

 towards the end of the same month. In a future 

 article we shall describe and illustrate this new 

 species. There can be but little doubt that, in 

 very many cases, these four larv», namely the 

 Spindle-worm, the Stalk Borer, the Corn-worm, 

 and our new species, which we shall take leave 

 to call Daggy 's Coru-worm {ProdeniaDagc/yi), 

 have been confounded together; more particu- 

 larly as the larva? of almost all Owlet-moths, 

 including the multifarious species of Cut-worms 

 CAgrotis and allies), present the same colora- 

 tional patterns, are very variable in their colora- 

 tion, and afibrd but very few strongly marked 

 and reliable distinctive characters. 



In those southerly districts, such as South 

 Illinois and Kentucky, where the Corn-worm is 

 a grievous pest to the farmer— since it is uow 

 probable that the first brood of this mischievous 

 insect occasionally matures in the undevel- 

 oped tassel of the corn-plant — it would possi- 

 bly pay to go through a field in July and break 

 otf and destroy the tops of all corn-plants that 

 appeared to contain one of these borers. If the 

 toppings were fed out immediately to stock. 



