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succession of hatches, there is but one rotation of metamorphoses consummated within a year. Hence borers, of all sizes, will be found in the trees throughout the year, although it seems to be necessary that all of them, whether more or less advanced, should pass through one winter before they appear in the winged state. Under its last form, this insect is a slender, dark blue, four-winged moth, having a slight resemblance to a wasp or ichneumon-fly, to which it is sometimes likened. The two sexes differ greatly from each other, so much so, as to have caused them to be mistaken for two distinct species. The male, which is much smaller than the female, has all the wings transparent, but bordered and veined with steel-blue, which is the general color of the body in both sexes; the palpi or feelers, the edges of the collar, of the shoulder-covers, of the rings of the abdomen, and of the brush on the tail, are pale yellow, and there are two rings of the same yellow color on the shins. It expands about one inch. The fore wings of the female are blue, and opake, the hind wings transparent, and bordered and veined like those of the male, and the middle of the abdomen is encircled by a broad orange-colored belt. It expands an inch and a half, or more. This insect does not confine its attacks to the peach-tree. I have repeatedly obtained both sexes from borers inhabiting the excrescences which are found on the trunks and limbs of the cherry-tree; and moreover, I have frequently taken them in connexion on the trunks of cherry and of peach trees. They sometimes deposit their eggs in the crotehes of the branches of the peach-tree, where the borers will subsequently be found; but the injury, sustained by their operations in such parts, bears no comparison to that resulting from their attacks at the base of the tree, which they too often completely girdle, and thus cause its premature decay and death. The following plan, which was recommended by me in the year 1826, and has been tried with complete success by several persons in this vicinity, will effectually protect the neck, or most vital part of the tree, from injury. Remove the earth around the base of the tree, crush and destroy the cocoons and borers which may be found in it, and under the bark, cover the wounded parts with the common
clay composition, and surround the trunk with a strip of sheathing paper eight or nine inches wide, which should extend two inches below the level of the soil, and be secured with strings of matting above. Fresh mortar should then be placed around the root, so as to confine the paper and prevent access beneath it, and the remaining cavity may be filled with new or unexhausted loam. This operation should be performed in the spring or during the month of June. In the winter the strings may be removed, and in the following spring the trees should again be examined for any borers that may have escaped search before, and the protecting applications should be renewed.
In Europe there is a species of Ægeria, named by Linnæus tipuliformis, which has long been known to inhabit the stems of the currant-bush. This, or an insect closely resembling it, is far too common in America, in the cultivated currant, with which it may have been introduced from Europe. The caterpillars are produced from eggs laid singly, near the buds; when hatched, they penetrate the stem to the pith, which they devour, and thus form a burrow of several inches in length in the interior of the stem. As the borer increases in size, it enlarges the hole communicating with its burrow, to admit of the more ready passage of its castings, and to afford it the means of escape when it is transformed to a moth. The inferior size of the fruit affords an indication of the operations of the borers; and the perforated stems frequently break off at the part affected, or, if of sufficient size still to support the weight of the foliage and fruit, they soon become sickly, and finally die. In some gardens, nearly every currant-bush has been attacked by these borers; and instances are known to me wherein all attempts to raise currant-bushes from cuttings have been baffled, during the second or third year of the growth of the plants, by the ravages of these insects. They complete their transformations, and appear in the moth state, about the middle of June. The moth is of a blue-black color; its wings are transparent, but veined and fringed with black, and across the tips of the anterior pair there is a broad band, which is more or less tinged with copper-color; the under side of the feelers, the collar, the edges of the shoulder-covers, and three very narrow rings on the abdomen, are golden yellow. The wings expand three quarters of an inch, or a little more.
Some years ago, it was ascertained that a species of Ægeria inhabited the pear-tree in this State; and it is said that considerable injury has resulted from it. An infested tree may be known by the castings thrown out of the small perforations made by the borers, which live under the bark of the trunk, and subsist chiefly upon the inner bark. They make their cocoons under the bark, and change to chrysalids in the latter part of summer. The winged insects appear in the autumn, having, like others of this kind, left their chrysalis skins projecting from the orifice of the holes which they had previously made. In its winged form, this Ægeria is very much like that which inhabits the currant-bush; but it is a smaller species. It was described by me in the year 1830, under the name of Ægeria Pyri, the pear-tree Ægeria; and my account of it will be found on the second page of the ninth volume of the “ New England Farmer.” Its wings expand rather more than half an inch; are transparent, but veined, bordered, and fringed with purplish black, and across the tips of the fore wings is a broad dark band glossed with coppery tints; the prevailing color of the upper side of the body is purple-black; but most of the under side is golden yellow, as are the edges of the collar, of the shoulder-covers, and of the fan-shaped brush on the tail, and there is a broad yellow band across the middle of the abdomen, preceded by two narrow bands of the same color. There are several more insects belonging to this group
in Massachusetts, one of which lives in the stems of the lilac, and another inhabits those of the wild currant, Ribes floridum. The winged male of the latter species is remarkable for the very long, slender, and cylindrical tuft or pencil at the extremity of the body. Of the rest, there is nothing particularly worthy of note.
See “Silliman's Journal,” Vol. XXXVI., p. 309 to 313.
The Glaucopidians," so named from the glaucous or bluish green color of some of the species, are distinguished from the other Sphinges by their antennæ, which, in the males at least, and sometimes in both sexes, are feathered, or furnished on each side with little slender branches, parallel to each other like the teeth of a comb. In scientific works such antennæ are called pectinated, from pecten, the Latin for comb. The caterpillars of the Glaucopidians have sixteen feet, are slender, . and cylindrical, with a few hairs scattered generally over the surface of the body, or arranged in little tufts arising from minute warts, and are without a horn on the hinder extremity. They devour the leaves of plants, and make for themselves cocoons of coarse silk, in which they undergo their transformations. The chrysalids are oblong oval, rounded at one end, tapering at the other, and are not provided with transverse rows of teeth on the surface of the body. In the caterpillar and winged states, in the nature of their transformations, and in their habits, these insects approach very closely to the Phalænæ, or moths, forming the third division of Lepidopterous insects, among which they are arranged by some naturalists. There are not many of them in Massachusetts, and only one species requires to be noticed here. f This is the Procris Americana, a small moth of a blue-black color, with a saffroncolored collar, and a notched tuft on the extremity of the body. The wings, which are very narrow, expand nearly one inch. This little insect is the American representative of the Procris vitis or ampelophaga of Europe, which, in the caterpillar state, sometimes proves very injurious to the grape-vine. The habits of our species are exactly the same; but have been overlooked, or very rarely observed in this vicinity. The caterpillars are gregarious, that is, considerable numbers of them live and feed together, collected side by side on the same leaf, and only disperse when they are about to make their cocoons. They are of a yellow color, with a transverse row of black velvety tufts on each ring, and a few conspicuous hairs on each extremity
* See additional observations on page 246. † For the other species see “Silliman's Journal," Vol. XXXVI., pp. 316 to 319.
of the body. They are hatched from eggs, which are laid in clusters of twenty or more together on the lower sides of the leaves of the grape-vine and creeper; and they come to their growth from the middle to the end of August. They then measure six tenths or rather more than one half of an inch in length. Their feet are sixteen in number, and rather short, and their motions are sluggish. When touched, they curl their bodies sidewise and fall to the ground, or, more rarely, hang suspended from the leaves by a silken thread. they eat only portions of the surface of the leaf; but, as they grow older they devour all but the stalk and principal veins, and passing from leaf to leaf, thus strip whole branches of their foliage. When numerous, they do much damage to the vines and fruit, by stripping off the leaves in midsummer, when most needed. I have found them in Massachusetts on the grape-vine and on the common creeper, or Ampelopsis quinquefolia, and conjecture that the latter constitutes their natural food. About the year 1830, Professor Hentz found them in swarms upon cultivated grape-vines at Chapel-Hill, in North Carolina; and constant care was required to check their ravages there, during several successive years. Several broods appeared there in the course of the summer; but hitherto, only one annual brood has been observed in Massachusetts, although two or more broods may occasionally be produced. When, about to make their cocoons, the caterpillars leave the vines, and retire to some sheltered spot. They then enclose themselves, each in a very thin but tough oblong oval cocoon, and soon afterwards are transformed to shining brown chrysalids. Early in July, and in the middle of the day, I have seen the moths flying about grape-vines and creepers, at which time, also, they pair and lay their eggs. A more full account of this insect, illustrated by figures, will be found in Hovey's “ Magazine,” for June, 1844.