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POTATO-BEETLE. THE BEETLE DESCRIBED. side its outline is nearly the form of a crescent. The head is small and much narrower than the fore part of the body, of a flattened spherical form. Its mouth is furnished with short, conical, jointed feelers and large jaws which are blunt at their ends, with little sharp teeth like those of a saw. Immediately above the mouth on each side of the head is a small conical and jointed projection, which is the antenna. The thorax has a large transverse space on the top of its first ring, of a firmer and somewhat coriaceous texture and broadly margined with black on its hind side and with dusky at each end. The abdomen is the thickest part of the body and is distinctly divided into nine segments. It is very plump and rounded, but flattened on its underside. It gradually tapers posteriorly into a conical point the apex of which is blunt and serves as a pro-leg, two small vesicular processes on its lower side at the end serving as feet. There are six legs, placed anteriorly, upon the breast, each leg being composed of three joints and ending in a small claw. The larva is of a pale yellow color, often slightly dusky or freckled on the back with minute blackish dots, and along each side are two rows of large black dots, those of the upper row larger, seven in number; not being continued upon the thoracic or the last abdominal rings, each dot having a small breathing pore in its centre. The head is black and shining, and more or less mottled on the face with dull yellowish. The neck or first ring has a black band near its hind edge; the second ring has also either a short black band or two black dots, whilst the third ring usually shows two small black dots on its back. On the narrow tip of the body are two black bands, the anterior one having at its end on each side a small black dot, and beyond this a large black dot which is the last one of the lower row of dots along the sides. On the next ring forward is a transverse row of six small equidistant black dots, in addition to the two large dots on each side, whereof the upper one is the last of the upper lateral row and the lower the penultimate one of the lower row. The legs are black; and often along the middle of the body, on the underside, is a row of transverse black spots or clouds, and also a row of small black dots upon each side. · The BEETLE or mature insect is 0.40 long and 0.25 thick, the female being
slightly larger. It is of a regular oval form, very convex above and flat beneath, of a hard crustaceous texture, smooth and shining, of a bright straw color, the head and thorax being sometimes tawny yellow, which is the color of the underside; and it is dotted and marked with black. After death its colors often fade, becoming more dull and dark. The head is nearly spherical and little more than half the width of the thorax, into which it is sunk nearly or quite to the eyes. It is sprinkled over with fine punctures and shows on the front an impressed medial line, and on each side of this a wider shallow indentation. On the crown is a triangular black spot. The nose piece or clypeus, occupying the space between the antennæ, is nearly semicircular and placed transversely, and is coarsely and closely punctured. The jaws are coarsely punctured, black at their tips, and have a slender black line along their outer edge. The tips of the palpi or feelers are dark brown. The antennæ rcach nearly to the base POTATO-BEETLE. TIS BEETLE DESCRIBED. REMEDIES. of the thorax when turned backward. They are gradually thickened towards their tips, twelve-jointed, the last joint being quite small, conical, and sunk into the apex of the preceding joint. The five first joints are pale yellow or tawny, obovate, the basal one largest, and the third one longer than either of the other three. The remaining joints are black and somewhat globular. The thorax is transverse, twice as broad as long, broadly notched in front for receiving the head, and its hind side convex. Five punctures are scat tered over its surface, these punctures becoming more numerous and coarser towards the outer sides. It is commonly margined all round by a slender black line. In the centre are two oblong black spots which diverge forward. Back of these is a small black dot which is often wanting; and on each side are about six small black spots; one towards the base, of an oval form and placed transversely; and two round ones, nearly upon a line forward of this, the three being equidistant from each other; two towards the hind angle, placed close together and often united, the inner one of these being largest of the six; and the sixth one placed half way between the two last and the forward angle. The scutel is dark brown. The wingcovers have the sutural edge dark brown, and five equidistant black stripes on each. The first or inner stripe is shortest and tapers backward as it gradually approaches the suture, terminating in a very long slender point a considerable space forward of the apex. The two next stripes are broadest and are united at their tips, beyond which they are sometimes prolonged into the end of the fourth stripe. The outer stripe is the most slender and longest of all, placed on the outer margin but terminating before it attains the apex. The wing covers are also punctured in rows extending along the margin of the stripes, the rows being uneven and the middle ones double; and the outer interspace is also punctured. Beneath, the sockets of the legs are black or edged with black, and on the hind breast is a transverse black spot on each side, forward of the insertion of the hind legs, and also a black stripe on the outer margin of the hind breast, outside of which on the parapleura is a triangular black spot. The abdomen is finely punctured on the disk and base, and has a short black band on the middle of the anterior edge of each seument except the last, and near the outer margin a row of six black dots. The legs are tawny yellow, with the hips at least of the hind pair black and also the knees and feet.
Say mentiuns a variety of this beetle having the wing-covers white. This is probably always their color when recently disclosed from the pupa.
What will be the best remedies for this new insect enemy can only be ascertained by experiments with it in its native haunts when its habits are more fully observed. We know not whether turkeys and other fowls relish these beetles, whereby they may be employed to aid in lessening their numbers. The large size of the beetles and their sluggish movements favor their being readily noticed and picked from off the vines. But their numbers are so immense as to dishearten from attempts to thus get rid of them unless sume way can be devised to gather them rapidly in large quantities. The method that has been resorted to with some success against the blistering flies where they have been numerous on the
GARDEN TIGER-MOTH. ITS AMERICAN HISTORY. MOTI DESCRIBED. potato vines, may be of utility, namely, holding a pan with an inch or two of water in it, under the vines here and there, and shaking and knocking the insects off into it, the water holding them from escaping until a quantity are gathered, when they may be emptied into a bag, and another quantity gathered. They can be killed by immersing the bag in boiling water, and its contents may then be fed to the swine.
11. GARDEN TIGER-MOTH, Arctia Caja, Linnæus. (Lepidoptera. Arctiidæ.)
Eating the leaves of lettuce, strawberries, &c., a large thick-bodied caterpillar nearly two inches long, of a black color with a row of white shining dots along each side and thickly clothes with long soft hairs which are black upon the back and red on the neck and sides; enclosing itself in a thin pale brown cocoon from which towards the end of July comes a large beautiful brown moth with white spots and many irregular stripes orossing its fore wings, its hind wings oobre yellow with about four large round blue black spots.
This truly elegant insect, named Caja or the bride by Linnæus, and the caterpillar of which is popularly called the Garden Tiger in England, is abundant all over Europe, but as yet is quite rare in this country. Several specimens were met with in our State at Trenton Falls, by Mr. Edward Doubleday, in 1837. A male has long been in my collection, which I think was taken the same year at Canajoharie and presented me by Wm. S. Robertson; and wủen closing these pages for the printer, on the evening of July 27th, 1864, a female came in at the open door of my study, flying slowly around with a rustling of its wings which indicated it to be some moth of a large size and heavy body.
One of Mr. Doubleday's specimens was presented to Dr. Harris, by whom, first in the year 1841, in his Report to the Legislature on the Insects of Massachusetts Injurious to Vegetation, it was described as a new species under the name Arctia Americana, although Godart had previously regarded it as identical with the Caja, in which opinion Boisduval and other French naturalists have since continued to concur. In Agassiz? Lake Superior, Dr. Harris gives a more full description and a figure of this moth, in which he says the white spots and rivulets on its fore wings are the same as in the European insect, but that it is distinguished from that by the white band margining the thorax in front. But in a European specimen which I have before me, this white band is present and conspicuous as in
American examples, except that it is less broad; which is a circumstance of no importance in an insect subject to such great variations in its colors and marks. Thus we are left without any grounds for regarding this as different from the European species.
. This moth measures from two and a half to three inches across its wings when they are extended, the males being a trifle smaller than the females. It is of a rich brown color, the hue of burnt coffee, with some of its parts bright ochre yellow or orange red, and it is variegated with spots and marks of milk white, crimson red, dark blue and black. But it varies astonishingly in its colors and marks. I draw the following description of the spots and markings chiefly from the living specimen before me, in which they appear to occur in their most usual and perfect condition. The head is brown. The palpi or feelers form two conical points projectLAG. TRANS.]
ing off two in underside. tips brown, whers
GARDEN TIGER-XOTH. ITS ASTONISHING VARIETIES OF COLOR. ing obliquely forward and downward from the lower front part of the head, of a darker brown with longer and less dense hairs of a red color along their underside and around the mouth. Coiled up between them is the spiral tongue, of a white color, and only equaling them in length when extended. The antennæ reach a third of the length of the wings. They resemble slender, tapering threads, white, their tips brown, their basal joint red, and a brown stripe along their underside. In the males they are pectinated, each joint sending off two short brown branches. The thoris is globular and brown, with a broad white band in front, occupying the base of the collar and extending backward across the shoulders and uniting with the white stripe or spot upon the middle of the base of the wings. The collar is edged all round with crimson red, forming a slender margin along the lower edge of the white band and on each side crossing this band and forming a narrow arched band above it. The base of the thorax is also slenderly margined with red, which color widens on each side into a small spot. The sides of the thorax are pale brown, with a pencil of red hairs in the axilla of the wings. The abdomen is bright ochre yellow with a row of brownish black spots along the middle of the back, the spots transverse, four or five in number, the hind ones largest. The underside is pale brown with the edges of the segments yellow. The wings are brown, slightly paler towards their hind ends. Their base is white, which color near the middle of each wing is prolonged backwards into a long acute point, forward of which are two long egg-shaped brown spots, placed side by side, and on the outer edge are two larger brown spots slightly parted from each other by a curved line, with a fifth spot on the inner edge. Towards the middle of each wing on the outer edge are two large white spots of an irregularly triangular form. Beyond these, crossing the wing transversely from the outer margin to the inner angle is a wavy white band which is thickened at its ends. From the middle of this band a curved branch extends forward and inward to the inner margin; and from the same point on the opposite side of the band another branch extends backward, nearly to the hind edge, when it abruptly turns outward and forward and then outward and backward, reaching the outer margin of the wing forward of the tip. In the closed wings these markings upon their hind part are observed to be beautifully symmetrical, having some resemblance to the Greek letter omega with a bar placed horizontally across its middle. The lower wings are deep ocbre yellow with four large round blackish blue spots having a black margin, whereof three are situated in a row forward of the hind margin, the inner one of these being the smallest, and the fourth one, which is slightly transverse, is placed forward of the centre. The undersides are colored and marked similarly but much more pale and dim. The legs are brown with the thighs crimson except upon their undersides, and the shanks and hind feet are yellow on their undersides. · In respect to its colors and spots, this moth is truly protean, varying to an extent which is most astonishing. Thus the fore wings are sometimes black instead of brown, with all vestiges of the white spots and rivulets upon them vanished. In other instances they are of the same bright yellow
GARDEN TIGER-MOTA. ITS EGGS. JATERPILLARS DESCRIBED. THE COCOON AND CHRYSALIS. or red color with the hind wings, with a few brown spots upon them; and in still other instances they are white with but a faint tinge of yellow. The hind wings sometimes have their spots diminished and nearly obliterated. In other instances these spots are increased in number and size; again, they become confluent, forming two broad black bands across the wing; and finally, the whole wing is black and without spots. The Arctia Parthenos it cannot be doubted is one of the latter varieties of this species, intermediate between the banded winged and black winged varieties. It is erroneously credited to Kirby in the Smithsonian Catalogue of Lepidoptera. It was described and figured by Dr. Harris, in Agassiz? Lake Superior, and is essentially distinguished as having the base and inner margin of its hind wings black with the remaining portion yellow crossed by a broad black band.
The female moth above mentioned dropped seven hundred and forty-four eggs in the course of four days after her capture. Being so prolific it is evident this insect would very soon become as abundant in our country as it is in Europe if it were not checked in its increase. It must be that nearly all the caterpillars of each generation are destroyed, probably by birds. Judging from the proceedings of the female when in confinement, her eggs are laid upon the surface of leaves and firmly glued thereto in clusters of from fifty to one hundred, the eggs in each cluster being placed for the most part in contact with each other in regular rows. The eggs are quite small, being about 0.034 in diameter. They are globular, shining, white, with a large faint spot on their summit of a watery appearance.
The caterpillars which come from these eggs grow to about two inches in length and have a thick cylindrical body which authors describe as being of a deep black color, densely covered with long soft hairs which arise in bundles from elevated warts. These hairs are of a bright red color on the three first rings and along the sides, and on the rest of the body are black with their ends gray. The warts from which the red hairs arise are of a bluish gray color; those from which the black ones come are blackish brown. Three of these warts of a blue color and placed in a row one above the other on each side of each ring are most obvious to the eye. The breathing pores form a row of shining white dots along each side. The head is shining black; the underside and feet are blackish brown. From all the other caterpillars of our country this is particularly distinguished by the three blue warts on each side of each segment, and the conspicuous row of white dots along each side of the body. As it approaches maturity, however, its unusually large size will alone suffice to point it out. It would appear to be this creature to which Hiawatha is represented to refer, in Longfellow's much admired poem, as
" The mighty caterpillar
King of all the caterpillars !" When it is fully grown it incloses itself in a grayish brown cocoon of a soft closely woven texture, intermixed with the hairs of its body. In this it changes to a chrysalis, having the form of an elongated egg, of a shining black color with the sutures yellowish brown and the pointed end two-lobed