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the beginning of July, and comes forth in the moth state near the end of August. The moth may be called Mamestra picta, the painted Mamestra, in allusion both to the beautiful tints of the caterpillar, and to the softly blended shades of dark and light brown with which the fore-wings of the moth are colored. It is of a light brown color, shaded with purple brown; the ordinary spots on the fore-wings, with a third oval spot behind the round one, are edged with gray; and there is a transverse zigzag gray line, forming a distinct W in the middle, near the outer hind margin. The hind-wings are white, and faintly edged with brown around the tip. It is evident that this insect cannot be included in either of the foregoing groups of the owlet-moths. It belongs to a distinct family, which may be called MAMESTRADE, or Mamestrians. The caterpillars in this group are generally distinguished by their bright colors; they live more or less exposed on the leaves of plants, and transform in the ground. The moths fly by night only; most of them have the thorax slightly crested; and they are easily known by the zigzag line, near the outer hind margin of the fore-wings, forming a W or M in the middle.

As the caterpillar of the painted Mamestra does not seek concealment, it may easily be found, and destroyed by hand.

At the end of the tribe of owlet-moths may be arranged certain insects, which, from the structure of their caterpillars and their manner of creeping, evidently seem to connect this tribe with the Geometers. Some of these caterpillars have the first and sometimes also the second pair of proplegs, under the middle of the body, so short, that they cannot be used in creeping; others have only twelve or fourteen legs, the first pair of the proplegs, or the second also, being entirely wanting in them. These caterpillars creep with a kind of halting gait, and arch up the middle of the body, more or less, with every step they take, thereby imitating the gait of the true geometers or span-worms. The twelve-legged caterpillars are sometimes injurious to cultivated vegetables; but not enough so, in this country, to have attracted much notice. Their moths are distinguished by golden or silvery spots on their fore-wings. The species, with the first and second pairs of proplegs short and rudimentary, feed mostly on the leaves of shrubs and trees; their moths are of large size,

with the hind-wings often crimson, scarlet, or yellow, and traversed by black bands. But as these insects are not particularly interesting to the farmer, any further account of them, in this treatise, will be unnecessary.

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The caterpillars of the GEOMETRE of Linnæus, earth-measurers, as the term implies, or geometers, span-worms, and loopers, have received these several names from their peculiar manner of moving, in which they seem to measure or span over the ground, step by step, as they proceed. Most of these caterpillars have only ten legs; namely, six, which are jointed and tapering, under the forepart of the body, and four fleshy proplegs, at the hinder extremity; the three intermediate pairs of proplegs being wanting. Consequently, in creeping, they arch up the back while they bring forward the hinder part of the body, and then, resting on their hind-legs, stretch out to their full length, in a straight line, before taking another step with their hind-legs. Some of the Geometers have twelve or fourteen legs; but the additional proplegs are so short that the caterpillars cannot use them in creeping, and their motions are the same as those that have only ten legs. Some caterpillars with fourteen legs, and wanting only the terminal pair of proplegs, are placed in this tribe on account of the resemblance of their moths to those of the true Geometers. The latter live on trees and bushes, and most of them undergo their transformations upon or in the ground, to reach which, by travelling along the branches and down the stem, would be a long and tedious journey to them, on account of the deficiency of their legs, and the slowness of their gait. But they are not reduced to this necessity; for they have the power of letting themselves down from any height, by means of a silken thread, which they spin from their mouths while falling. Whenever they are disturbed they make use of this faculty, drop suddenly, and hang suspended, till the danger is past, after which they climb up again by the same thread. In order to do this, the span-worm bends back its head and catches hold of the thread above its head with one of the legs of the third segment, then raising its head it seizes the thread with its jaws and fore-legs, and, by repeating the same

operations with tolerable rapidity, it soon reaches its former station on the tree. These span-worms are naked, or only thinly covered with very short down; they are mostly smooth, but sometimes have warts or irregular projections on their backs. They change their color usually as they grow older, are sometimes striped, and sometimes of one uniform color, nearly resembling the bark of the plants on which they are found. When not eating, many of them rest on the two hindmost pairs of legs against the side of a branch, with the body extended from the branch, so that they might be mistaken for a twig of the tree; and in this position they will often remain for hours together. When about to transform, most of these insects descend from the plants on which they live, and either bury themselves in the ground, or conceal themselves on the surface under a slight covering of leaves fastened together with silken threads. Some make more regular cocoons, which, however, are very thin, and generally more or less covered on the outside with leaves. The cocoons of the European, tailed Geometer (Ourapteryx sambucaria), which lives on the elder, and of our chain-dotted Geometer (Geometra catenaria), which is found on the wood-wax, are made with regular meshes, like net-work, through which the insects may be seen. A very few of the span-worms fasten themselves to the stems of plants, and are changed to chrysalids, which hang suspended, without the protection of any outer covering.

In their perfected state these insects are mostly slender-bodied moths, with tapering antennæ, which are often feathered in the males. Their feelers are short and slender; the tongue is short and weak; the thorax is not crested; the wings are large, thin, and delicate, sometimes angular, and often marked with one or two dark-colored oblique bands. They generally rest with the wings slightly inclined and almost horizontal; some with them extended, and others with the hind-wings covered by the upper pair. A very few carry their wings like the Skippers. Some of the females are without wings, and are distinguished also by the oval and robust form of their bodies. These moths are most

active in the night; but some of them may be seen flying in thickets during the day-time. They are very short-lived, and die soon after their eggs are laid.

Those kinds, whereof the females are wingless, or have only very short, scale-like wings, and naked antennæ, while the males have large, entire wings, and feathered or downy antennæ, seem to form a distinct group, which may be named Hybernians (HyBERNIADE), from the principal genus included therein. The caterpillars have only ten legs, six before and four behind; and they undergo their transformations in the ground. The insects called canker-worms, in this country, are of this kind. The moths, from which they are produced, belong to the genus Anisopteryx,* so named because in some species the wings in the two sexes are very unequal in size, and in others the females are wingless. In the late Professor Peck's "Natural History of the Canker-worm," which was published among the papers of "the Massachusetts Society for Promoting Agriculture," and obtained a prize from the Society, this insect is called Phalana vernata, on account of its common appearance in the spring, and also to distinguish it from the winter moth (Phalana or Cheimatobia brumata) of Europe. In the male canker-worm moth the antennæ have a very narrow, and almost downy edging, on each side, hardly to be seen with the naked eye. The feelers are minute, and do not extend beyond the mouth. The tongue is not visible. The wings are large, very thin and silky; and, when the insect is at rest, the fore-wings are turned back, entirely cover the hindwings, and overlap on their inner edges. The fore-wings are ash-colored, with a distinct whitish spot on the front edge, near the tip; they are crossed by two jagged, whitish bands, along the sides of which there are several blackish dots; the outermost band has an angle near the front edge, within which there is a short, faint, blackish line; and there is a row of black dots, along the outer margin, close to the fringe. The hind-wings are pale ash-colored, with a faint blackish dot near the middle. The wings expand about one inch and a quarter. This is the usual appearance of the male, in its most perfect condition; by which it will be seen that it closely resembles the Anisopteryx Æscularia of Europe. Compared with the latter, I find that our canker-worm moth is rather smaller, the wings are darker, propor

Literally unequal wing.

tionally shorter and more obtuse, the white bands are less distinct, and are often entirely wanting, in which case only the whitish spot near the tip remains, the hind-wings are more dusky, and the feelers are gray instead of being white. Specimens, of a rather smaller size, are sometimes found, resembling the figure and description given by Professor Peck, in which the whitish bands and spot are wanting, and there are three interrupted dusky lines across the fore-wings, with an oblique blackish dash near the tip. Perhaps they constitute a different species from that of the true canker-worm moth. Should this be the case, the latter may be called Anisopteryx pometaria, or the Anisopteryx of the orchard, while the former should retain the name originally given to it by Professor Peck. The female is wingless, and its antennæ are short, slender, and naked. Its body approaches to an oval form, but tapers and is turned up behind. It is dark ashcolored above, and gray beneath.

It was formerly supposed that the canker-worm moths came out of the ground only in the spring. It is now known that many of them rise in the autumn and in the early part of the winter. In mild and open winters I have seen them in every month from October to March. They begin to make their appearance after the first hard frosts in the autumn, usually towards the end of October, and they continue to come forth, in greater or smaller numbers, according to the mildness or severity of the weather after the frosts have begun. Their general time of rising is in the spring, beginning about the middle of March, but sometimes before, and sometimes after this time; and they continue to come forth for the space of about three weeks. It has been observed that there are more females than males among those that appear in the autumn and winter, and that the males are most abundant in the spring. The sluggish females instinctively make their way towards the nearest trees, and creep slowly up their trunks. In a few days afterwards they are followed by the winged and active males, which flutter about and accompany them in their ascent, during which the insects pair. Soon after this, the females lay their eggs upon the branches of the trees, placing them on their ends, close together in rows, forming clusters of from sixty to one hundred eggs or more, which is the number usually laid by

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