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CUT-WORMS. WINGS OF THE HOTH DESCRIBED. wings are spread. It is gray, with a black band in front, edged on its hind side with an ash gray one, paler than the ground; and on the shoulder at the base of the fore wings is usually a small spot of dull pale yellow. The abdomen is tapering and somewhat flattened, dusky grayish, paler towards its base, its tip more blunt in the male than in the female and covered with a brush of hairs. The legs are blackish gray and hairy on their undersides, the spurs at the end of the middle and hind shanks being black in their middle and white at each end. The feet are five-jointed, long and tapering, the first joint much the longest and the following ones successively shorter. They are gray, gradually passing into black at their ends, each joint having a white ring at its tip. The wings in repose are laid flat, one upon the other, in a horizontal position, sometimes so closed together that their opposite sides are parallel, but oftener widening back. ward (as represented in figure 3), and forming a broad shallow notch at their hind end. The fore wings vary in color from ash gray to dusky gray, and sometimes have a tawny reddish reflection. Their outer edge is grayish black, with irregular alternations of black spots having an ash gray spot between them, and towards the tip are about three equidistant pale gray dots. The costal area or narrow space between the outer edge and the first longitudinal vein is pale ash gray, gradually becoming dull and obscure beyond the middle. At the base, on the outer edge, are two black spots or short transverse streaks, with a pale gray streak between them, and opposite these, on the basal middle of the wing, are similar streaks placed obliquely, which are frequently faded to a blackish cloud-like spot, with a pale gray streak crossing its middle.. Outside of the central part of the wing are the stigmas, two large roundish pale gray spots, having a square coal-black spot between them and a triangular one forward of them. The anterior one of these stigmas is broad oval, almost circular, and placed obliquely, with its outer end more towards the base of the wing than is the inner end. It is of a uniform pale gray color, slightly paler than any other part of the wing. Its edge is well defined by the black color surrounding it, except at its outer end, where it is incomplete, being confluent with the ash gray color of the costal area. The hinder stigma is kidney-shaped, being concave on its hind side, and occupying this concavity is a pale gray spot or cloud, quite variable in its size in different specimens, and frequently taking on a buff or cream yellow tinge. This stigma is brownish or watered gray, becoming paler along its anterior edge, its ends, particularly the inner one, being vague and indefinite, blending with the adjacent coloring, sometimes so much so that only its middle portion is distinct. Between these stigmas is a large square spot of a coal black color, occupying the whole space between the two midveins of the wings, its fore and hind sides made concave by the rotundity of the stigmas which bound it upon these sides. Forward of the anterior stigma is a second black spot of a somewhat triangular form, also occupying the whole space between the two midveins at this point. On its hind side it is concave and cut off obliquely by the obliquity of the stigma, whereby it is prolonged along the inner vein, usually into a long acute
CUT-WORMS. DESCRIPTION OF THE WINGS CONTINUED. point. Its anterior end is cut off, either transversely, obliquely or irregularly, by a faint pale gray streak, which is a portion of the anterior or extra-basal band. (See generalities preceding the description of the wings of the Tobacco-worm moth). In the best specimens this pale streak is distinctly seen to be prolonged backwards along the outer side of the black spot almost to the stigma, and then suddenly turning at a right angle, it runs obliquely forward and outward in a straight line to the outer margin, between the two small black spots which are here placed on the margin. In the opposite direction this pale streak is also prolonged from the forward end of the black triangular spot, inward and backward aud curves slightly forward to the inner longitudinal vein, and beyond this, with another, similar curve, is extended to the inner edge of the wing, it being margined on both sides by a black line, that along its hind side being commonly more conspicuous. And a short distance back from this line, equidistant between the inner midvein and the inner vein, may always be seen a black dot or short dash, which is the extreme point of a black stripe called the teliform stigma, which is common upon the wings of the moths of this genus, but in this variety of this species is wholly wanting, except this minute vestige of its apex. And also crossing this inner half of the wing obliquely at about two-thirds of the distance from the base to the hind edge are two other parallel blackish lines, representing the post-medial band. The anterior one of these lines is irregularly wavy and angular, and turns obliquely forward as it approaches the posterior stigma, and appears to pass into the inner hind angle of the square black spot. The posterior line, as traced from the inner edge of the wing, curves slightly backward till it reaches a point a short distance back of the inner end of the hind stigma, when it becomes nearly transverse, and then curves forward and obliquely outward to the outer edge of the wing, ending in the posterior one of the two black spots which are on the outer edge opposite to the anterior side of the hind stigma. This line, in the middle of the wing, is festooned or made up as it were of crescents united at their ends, these ends projecting backwards and forming about four acute angular points ; and sometimes this line is made more distinct by a faint pale gray line bordering it on its hind side, at least in the concavities of the crescents. But both these blackish lines are commonly quite faint and entirely vanish in many specimens. Beyond this, a broad space on the hind border of the wing is darker colored and traversed by a whitish line, which is wavy and often broken into a series of small irregular spots, these spots sometimes having larger black cloud-like spots abjoining them on the fore side. Back of the outer end of this line the tip of the wing is occupied by a triangular gray spot. The hind edge is faintly sinuated, with a series of slender black crescents surmounting the sinuosities. The fringe is concolor with the portion of the wing immediately forward of it. The hind wings are smoky whitish, with a broad dusky hind border, dusky veins, and an obscure dusky crescent near the centre. Their fringe is dull white with a dusky band near its middle. On the underside they are clearer. white, with a broad dusky hind border and sprinkled with dusky scales CUT-woRMS. NAME OF THE MOTH. DESTROYER OF THE CUT-WORMS. towards the outer side. The veins are not marked with dusky, except a spot or short streak upon each of them, forming a transverse row forward of the hind border, which row becomes obsolete towards the inner edge and towards the outer edge is confluent, forming a dusky band. The central crescent is more distinct than on the upper side, and on the hind edge is a row of slender black crescents. The fore wings are dusky, of the same shade with the border of the hind pair, becoming slightly paler towards their bases. They show an obliquc black streak on the outer edge between the middle and the tip, and immediately beyond this is a very faint band crossing the wing parallel with the hind margin.
The description now given makes it apparent, I think, that this moth is not essentially different from the species of Agrotis named nigricans by Linnæus, which species we have upon this continent with the same varieties described by authors as occurring in Europe. In this species the teliform stigma is marked by two parallel lines connected by a rounded mark at their ends. But in the examples which I bred from the Cut-worms of the corn, and all those which I captured that season a mere dot was the only remaining vestige of this stigma. Therefore to facilitate future references to this particular variety of which I have here treated, it may be well to separate it under a distinct name, which I have accordingly done.
The larger Yellow-headed Cut-worm which came out as this was disappcaring, produced as I expected, the same moth which was described in my Third Report, under the name Hadena amputatrix, the Amputating brocade moth.
Thus it was the larvæ of these two insects which were so numerous and did all the injury to our crops the past season, neither of these being the species which Mr. Brace describes as the insect which produces the Cutworm. And it is therefore evident that in different years and at different localities, it is sometimes one sometimes another of the insects of this group which becomes multiplied and injurious to us; whereby it will require a series of observations extending through several seasons to obtain a full acquaintance with them.
Before leaving this subject I may advert to one of our most efficient natural destroyers of these Cut-worms, which correspondents are occasionally sending me, for information as to its name, its origin, &c. It is the larva of a large black beetle, (Plate 4, fig. 4),' having rows of round dots upon its back resembling burnished gold, the brilliancy of which dots 'cause it to be frequently noticed as it is wandering about in plowed fields and pastures in search of food, the beetle as well as its tarva subsisting upon these Cut-worms. It is the Bold Calosoma, Calosoma calidum as it is named in scientific works, and pertains to the order COLEOPTERA and the family Cara. BIDÆ.
Its larva (Plate 4, fig. 5,) is a flattened, black, worm-like creature, having six legs inserted upon its breast, and a pair of sharp hook-like jaws projecting in front of its head, giving it, in connection with the agility of its movements, a very ferocious and formidable appearance. It is curious to watch this little creature when it is upon a hunting excursion, in pursuit
CUT-WORMS. THEIR DESTROYER'S MODE OF KILLING THEM. of its prey. It wanders about over the plowed land, until it comes upon a spot where it perceives the surface has been newly disturbed. This indicates to it that a worm has probably crawled down into the ground at that spot. It immediately thereupon roots down into this loosened dirt, and disappears from view, the motion of the dirt indicating its movements, as it pushes itself along. At times it lies perfectly still, to discover if any worm is moving in the dirt anywheres near it. Now it is the habit of the Cut-worm, the same as of most other worms, when any other creature approaches and disturbs it, to give at short intervals a sudden, spiteful jerk, to menace and frighten away the intruder. But now, aware by the brisk motion made in the dirt near it, of the proximity of its mortal foe, it restrains itself from its wonted habit, and lies as still as though it were dead. It is only by some motion in the dirt, or by coming abruptly against it with its head and feelers, that this destroyer'can discover the worm, for I have seen it draw the hind part of its body along the side of a worm which was lying perfectly still, and crawl away, without being made aware of the worm's presence by touching it in this manner.
One of the most interesting and wonderful exhibitions of insect economy which the world affords, is this Calosoma larva murdering a Cut-worm. The larva it may be is young and less than half the size of the worm, but the liitle hero never shrinks from the encoupter. Upon discovering a worm, he is instantly on the alert, all vivacity and as if crazy with excitement. The worm perhaps holds its head bent down stiffly upon its breast. The larva hereupon briskly roots and pushes the worm about and pinches it with his jaws, whereby he gets it to throw back its head, whereupon hę instantly grasps the worin. by its throat, sinking his sharp jaws through the skin, and clinging thereto with the grip and pertinacity of a bull dog. The worm maddened by the pain writhes and rolls over and over and thrashes his tormentor furiously about, to break him off from his hold; he coils his body like a Boa constrictor tightly around him to pull him away; he bends himself into a ring with a small orifice in the centre, and then briskly revolving, draws him through and through this orifice to tear him off; but every expedient of the poor worm fails. The larva clings to his grip upon the worm's throat, till the latter, exhausted by his violent struggles, gradually relaxes his efforts, becomes more and more weak and powerless, arid finally succumbs to his fate. Having thus killed the worm the larva leisurely proceeds to feed upon it, biting two or three boles through the skin in different places to suck out its contents. It is occupied three or four hours in completing this work. And the larva becomes so gorged hereby that its own skin is distended almost to bursting. It then crawls slightly under ground, and there lies and sleeps off its surfeit, and then comes out and wanders off in search of another meal of the same kind.
When this larva is small a single Cut-worm suffices it for one or two days; but as it approaches maturity it devours one or two worms daily.
BEE-KILLER. A NEW INSECT. ITS CLASSIFICATION AND NAIK.
13. NEBRASKA BEE-KILLER, Trupanea dpivora, new species. (Diptera.
Asilidæ.) Plate 4, fig. 7. Killing the honey bee in Nebraska; a large slender-bodied two-winged fly, an inch long.
Whilst we are occupied in closing this Report to place it in the printer's hands, July, 1864, a new insect comes under our examination, of such an interesting character that we herewith present a figure of it, and the following account, the principal portion of which we have also communicated to the Country Gentleman.
R. 0. Thompson, Esq., Florist and Nurseryman, in a note dated Nursery Hill, Otoe county, Nebraska, June 28th, 1864, says: "I send you to-day four insects or animals that are very destructive to the honey bee, killing a great number of them, and also of the Rose bugs. What are they? Many wish to know what this Bee-killer is. Is it the male or the female that has the three-pronged sting ?"
The specimens, two of each sex, laid between pledgets of cotton wool in a small pasteboard box and forwarded by mail, came to hand in good condition, admitting of a very satisfactory examination. They are a large two-winged Ay, having a long and rather slender and tapering body, about an inch in length, with small three-jointed antennæ, the last joint being shorter than the first, and giving out from its end, and not froin its side, a slender bristle. The ends of its feet are furnished on the underside with two cushion-like soles, and the crown of its head is hollowed out or concave, and in this hollow is seen three little glassy dots or eyelets. These characters show it to pertain to the order Diptera, and to the group which Linnæus a century ago separated as a genus, under the name Asilus, but which is now divided into several genera, forming the family Asilidæ. On inspecting its wings we see the two veins which end one on each side of the tip of the wing are perfect and unbroken, and towards the middle of the outer one they are connected together by a small veinlet or short transverse vein. This indicates these flies to pertain to the genus named Trupanea by Macquart.
About a half dozen species inhabiting the United States and pertaining to this genus have been described by Wiedemann, Say, and others. This Nebraska fly appears to be different from either of those, and I am, therefore, led to regard it as a new insect, hitherto unknown to the world. And a more appropriate name cannot be given it than that by which it is called by Mr. Thompson and his neighbors, the Bee-killer or Trupanea Apivora. The general definition of this species, or its brief essential characters will be, that it is dull black with the head yellow, the fore body butternut brown, the hind body on its underside and the legs pale dull yellow, the thighs being black on their foresides, and it is coated over with hairs which are gray in the female and grayish yellow in the male, the end of the body in the latter sex having a conspicuous silvery white spot..
In this Asilus group of flies the species are separated from each other by marks which are often very slight and obscure. It is, therefore, important that a detailed description of these Nebraska flies should here be