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The largest of these moths may be called Agrotis telifera, the lance-rustic. It closely resembles Agrotis suffusa, the dark sword-rustic of Europe. The fore wings are light brown, shaded with dark brown along the outer thick edge, and in the middle also in the female; these wings are divided into three nearly equal parts by two transverse bands, each composed of two wavy dark brown lines; in the middle space are situated the two ordinary spots, together with a third oval spot, which touches the anterior band; these spots are encircled with dark brown, and the kidney-spot bears a dark brown lance-shaped mark on its hinder part; the hindmost third of the wing is crossed by a broad pale band, and is ornamented by a narrow wavy or festooned line, and several small blackish spots near the margin. The hind wings are pearly white, and semitransparent, shaded behind, and veined with dusky brown. The thorax is brown or gray-brown, with the edge of the collar blackish. The abdomen is gray. The wings expand two inches or more.
Another of these moths is the counterpart of the æqua and agricola of Europe. It also resembles the telifera in form, but is destitute of the lance-shaped spot on the fore wings; and hence I have named it Agrotis inermis, the unarmed rusticmoth. The fore wings are light brown, shaded in the middle and towards the hinder margin with dusky brown; they are crossed by four, more or less distinct, wavy bands, each formed of two blackish lines; the kidney-spot is dusky; and there are several blackish spots on the outer thick edge of the wing. The hind wings are pearly white in the middle, shaded behind and veined with dusky brown. The thorax is reddish brown, with the collar and shoulder-covers doubly edged with black. The abdomen is gray. It expands two inches.
The reaping rustic (Agrotis messoria), as it may be called, is the representative of the corn-rustic (Agrotis segetum) of Europe. The fore wings are reddish gray, crossed by five wavy blackish bands, the first two of which, and generally the fourth also, are double; the two ordinary spots, and a third oval spot near the middle of the wing, are bordered with black. The hind wings are whitish, becoming dusky brown behind, and have a small central crescent and the veins dusky. The head and thorax are chinchilla-gray; the collar is edged with black; and the abdomen is light brownish gray. It expands one inch and four tenths.
The smallest of these rustic moths may be called Agrotis tessellata, the checkered rustic. It probably comes near to the ocellina and aquilina of Europe, which, however, I have not seen. The fore wings are dark ash-colored, and exhibit only a faint trace of the transverse double wavy bands; the two ordinary spots are large and pale, and alternate with a triangular and a square deep black spot; there is a smaller black spot near the base of the wing. The hind wings are brownish gray in the middle, and blackish behind. It expands one inch and one quarter.
The fifth species I am assured by one of my friends is the moth of the cabbage cut-worm. It agrees, in the main, with the description given of the Phalana Noctua devastator, by Mr. John P. Brace, in the first volume of Professor Silliman's “ American Journal of Science;" and may therefore be called Agrotis devastator. It somewhat resembles Dr. Boisduval's figures of the Agrotis latens of Europe. The fore wings are of a dark ashen gray color, with a lustre like satin; they are crossed by four narrow wavy whitish bands, which are edged on each side with black; there is a transverse row of white dots followed by a row of black, arrow-shaped spots, between the third and fourth bands, and three white dots on the outer edge near the tip; the ordinary spots are edged with black and white, and there is a third spot, of an oval shape and blackish color, near the middle of the wing, and touching the second band. The hind wings are light brownish gray, almost of a dirty white in the middle, and dusky behind. The head and thorax are chinchilla-gray; and the abdomen is colored like the bind wings. It expands from one inch and five eighths to one inch and three quarters. This kind of moth is
very common between the tenth of July and the middle of August. Like all the foregoing species, it flies only at night. According to Mr. Brace, this moth lays its eggs in the beginning of autumn, at the roots of trees, and near the ground; the eggs are hatched early in May; the cut-worms continue their depredations about four weeks, then cast their skin and become pupæ or chrysalids in the earth, a few inches below the surface of the ground; the pupa state lasts four weeks, and the moth comes out about the middle of July; it conceals itself in the crevices of buildings and beneath the bark of trees, and is never seen during the day; about sunset it leaves its hidingplace, is constantly on the wing, is very troublesome about the candles in houses, Alies rapidly, and is not easily taken.* From what is known respecting the history of the other kinds of Agrotis, and from the size that the cabbage cut-worms are found to have attained in May, I am led to infer that they must generally be hatched in the previous autumn, and that, after feeding awhile on such food as they can find immediately under the surface of the soil, they descend deeper into the ground and remain curled up, in little cavities which each one makes for itself in the earth, till the following spring.
Dr. F. E. Melsheimer, of Dover, Pennsylvania, has favored me with the wing of a moth, which he states is produced from the corn cut-worm. The following remarks on this insect are extracted from his letters. “ There are several species of Agrotis, the larvæ of which are injurious to culinary plants; but the chief culprit with us is the same as that which is destructive to young maize.” “The corn cut-worms make their appearance in great numbers at irregular periods, and confine themselves in their devastations to no particular vegetables, all that are succulent being relished by these indiscriminate devourers; but, if their choice is not limited, they prefer maize plants when not more than a few inches above the earth, early sown buckwheat, young pumpkin-plants, young beans, cabbage-plants, and many other field and garden vegetables.” “When first disclosed from the eggs they subsist on the various grasses. They descend in the ground on the approach of severe frosts, and reappear in the spring about half grown. They seek their food in the night or in cloudy weather, and retire before sunrise into the ground, or beneath
# “ American Journal of Science," Vol. I., p. 154.
stones or any substance which can shelter them from the rays of the sun; here they remain coiled up during the day, except while devouring the food which they generally drag into their places of concealment. Their transformation to pupæ occurs at different periods, sometimes earlier, sometimes later, according to the forwardness of the season, but usually not much later than the middle of July.” “The moths, as well as the larvæ, vary much in the depth of their color, from a pale ash to a deep or obscure brown. The ordinary spots of the upper wings of the moth are always connected by a blackish line; where the color is of the deepest shade these spots are scarcely visible, but when the color is lighter they are very obvious.” Since the foregoing was written, I have repeatedly obtained the same moths from cut-worms here. The latter seem, indeed, to be the most common kind; but they differ very little from the cut-worms already described. They vary somewhat in color, as remarked by Dr. Melsheimer. Young ones are always more or less distinctly marked above with pale and dark stripes, and are uniformly paler below. The moth is very abundant in the New England States, from the middle of June till the middle or end of August. The fore wings are generally of a dark ash-color, with only a very faint trace of the double transverse wavy bands that are found in most species of Agrotis; the two ordinary spots are small and narrow, the anterior spot being oblong oval, and connected with the oblique kidney-shaped spot, by a longitudinal black line. The hind wings are dirty brownish white, somewhat darker behind. The head, the collar, and the abdomen are chestnut-colored. It expands one inch and three quarters. The wings, when shut, overlap on their inner edges, and cover the top of the back so flatly and closely that these moths can get into very narrow crevices. During the day they lie hidden under the bark of trees, in the chiuks of fences, and even under the loose clapboards of buildings. When the blinds of our houses are opened in the morning, a little swarm of these insects, which had crept behind them for concealment, is sometimes exposed, and suddenly aroused from their daily slumber. This kind of moth has the form and general appearance of some species of Pyrophila, but not the essential characters of the genus. It differs also from Agrotis and Graphiphora in some respects, and therefore I have thought it best to leave it, for the present, in the old genus Noctua, under the specific name of clandestina, the clandestine owlet-moth.
Among the various remedies that have been proposed for preventing the ravages of cut-worms in wheat and corn fields, may be mentioned the soaking of the grain, before planting, in copperas-water and other solutions supposed to be disagreeable to the insects; rolling the seed in lime or ashes; and mixing salt with the manure. These may prevent wireworms (Iuli) and some insects from destroying the seed; but cut-worms prey only on the sprouts and young stalks, and do not eat the seeds. Such stimulating applications may be of some benefit, by promoting a more rapid and vigorous growth of the grain, by which means the sprouts will the sooner become so strong and rank as to resist or escape the attacks of the young cut-worms. Fall-ploughing of sward-lands, which are intended to be sown with wheat or planted with corn the year following, will turn up and expose the insects to the inclemency of winter, whereby many of them will be killed, and will also bring them within reach of insect-eating birds. But this seems to be a doubtful remedy, against which many objections have been urged.* The only effectual remedy at present known, has been humorously described by Mr. Asahel Foote in the “ Albany Cultivator," and reprinted in the seventeenth volume of the “ New England Farmer.” After having lost more than a tenth part of the corn in his field, he “ ordered his men to prepare for war, to sharpen their finger ends, and set at once about exhuming the marauders. For several days it seemed as if a whole procession came to each one's funeral, but at length victory wreathed the brow of perseverance; and, the precaution having been taken to replace each foe dislodged with a suitable quantity of good seed-corn, he soon had the pleasure to see his field restored, in a good measure, to its original order and beauty, there being seldom a vacancy in a
* See Mr. Colman's “Third Report of the Agriculture of Massachusetts,” p. 62.