which remains to be described;—it measures about half an inch from the tip of the horn to the end of the body; the male is blackish above, with a long yellow spot on each side of the back; and the female is ash-colored, and without spots. While on the trees, these insects, though perfectly still, are not unemployed; but puncture the bark with their sharp and slender beaks, and imbibe the sap for nourishment. The female also appears to commit her eggs to the protection of the tree, being furnished with a piercer beneath the extremity of her body, with which to make suitable perforations in the branches. As I have never seen the young on these trees, I presume that, as soon as they are hatched, they make their way to the ground, and remain under the surface of the soil, sucking the sap from the roots of plants, until they are about to enter upon their last period of existence, when they crawl up the trunks of the trees, throw off their coats, and appear in the perfect or winged state. From the great numbers of these tree-hoppers which exist in certain seasons, the locust-trees undoubtedly suffer much, not only in consequence of the quantity of sap abstracted from their branches, but from the numerous punctures made by the insects in obtaining it and in laying their eggs.

The oak-tree is attacked by another species, the white-lined tree-hopper (M. univittata), which may be found upon it during the month of July. It is about four tenths of an inch in length; the thorax is brown, has a short obtuse horn extending obliquely upwards from its fore part, and there is a white line on the back, extending from the top of the horn to the hinder extremity.

The common creeper (Ampelopsis quinquefolia) is inhabited by a tree-hopper, which has an oblong square and thin elevation or crest on the middle of the thorax. Its body is usually of a reddish ash-color, and the thorax is ornamented with three reddish brown bands, one of which is above the head and extends transversely between the lateral projecting angles of the thorax, the second is a short and oblique line on each side of the front part of the crest, and the third is also oblique, and begins on the outer edge of the thorax, and passes obliquely

forwards on each side to the top of the hind part of the crest. This species may be called Membracis Ampelopsidis,* from the plant on which it is found in the perfect state. The young appear to live in the earth till they are fully grown and have acquired the rudiments of wing-covers and wings, or have become pupæ, after which they are seen ascending the stems of the creeper, on which they change their skins for the last time. This occurs from the middle to the end of June.

There is a little tree-hopper, which is found during the months of July and August on the wax-work, or Celastrus scandens, accompanied usually by its young. When fully grown it is nearly three tenths of an inch in length, including the horn of the thorax; is of a dusky brown color, with two yellowish spots on the ridge of the back; and the first four shanks are exceedingly broad and flat. It is the two-spotted tree-hopper, or Membracis binotata of Say. When seen sidewise it presents a profile much like that of a bird, the head and neck of which are represented by the curved projecting horn of the thorax; and a group of these little tree-hoppers, of various sizes, clustered together on a stem of the wax-work, may be likened to a flock of old and young partridges. They appear to pass through all their transformations on the plant, are fond of society, and sit close together, with their heads all in the same direction.

Tree-hoppers are often surrounded by ants, for the sake of their castings, and for the sap which oozes from the punctures made by the former, of which the ants are very fond. Those kinds, that live on the stems of plants from the time when they are hatched till they are fully grown, are very closely attended by ants; and, as from their constant sucking the young become often wet, their careful attendants, the ants, find regular employment in wiping them clean and dry with their antennæ and tongues.

The remaining Homopterous insects have a thorax of moderate size, not tapering to a point behind, and not covering the whole body as in the preceding species. Their heads are

* It is the Membracis Cissi of my Catalogue.

visible from above, and the face slopes downwards towards the breast.

Here may be arranged the singular insects called froghoppers (CERCOPIDIDE), which pass their whole lives on plants, on the stems of which their eggs are laid in the autumn. The following summer they are hatched, and the young immediately perforate the bark with their beaks, and begin to imbibe the sap. They take in such quantities of this, that it oozes out of their bodies continually, in the form of little bubbles, which soon completely cover up the insects. They thus remain entirely buried and concealed in large masses of foam, until they have completed their final transformation, on which account the names of cuckoo-spittle, frog-spittle, and froghoppers have been applied to them. We have several species of these frog-hoppers in Massachusetts, and the spittle, with which they are sheltered from the sun and air, may be seen in great abundance, during the summer, on the stems of our alders and willows. In the perfect state they are not thus protected, but are found on the plants, in the latter part of summer, fully grown and preparing to lay their eggs. In this state they possess the power of leaping in a still more remarkable degree than the tree-hoppers; and, for this purpose, the tips of their hind shanks are surrounded with little spines, and the first two joints of their feet have a similar coronet of spines at their extremities. Their thorax narrows a little behind, and projects somewhat between the bases of the wing-covers; their bodies are rather short, and their wing-covers are almost hori zontal and quite broad across the middle, which, with the shortness of their legs, gives them a squat appearance."

The leaf-hoppers (TETTIGONIADE) leap almost as well as the spittle-insects just mentioned; but their hind legs are longer, are not surrounded with coronets of short spines, but are three sided, and generally fringed on two of their edges

The following species are found in Massachusetts, namely: Cercopis ignipecta of my Catalogue, and the parallela, quadrangularis, and obtusa, of Say. The last three belong to Germar's genus Aphrophora, which means spumebearer. Cercopis, which may be translated impostor, was applied by the Greeks to a small Cicada.

with numerous long and slender spines, which contribute, like the coronets of the frog-hoppers, to fix their shanks firmly when they are about to leap. The leaf-hoppers have been divided, by Professor Germar and other entomologists, into many genera, according to the structure of their legs, the situation of the eyelets, and the form of the head; but we may retain them, without inconvenience, in the genus Tettigonia, proposed for them by Geoffroy, or rather adopted from the ancient Greeks, who gave this name to the small kinds of harvest-flies, calling the larger ones Tettix. The Tettigonians, or leaf-hoppers, have the head and thorax somewhat like those of frog-hoppers, but their bodies are, in general, proportionally longer, not so broad across the middle, and not so much flattened. The head, as seen from above, is broad, and either crescent-shaped, semicircular, or even extended forwards in the form of a triangle; its upper side is more or less flattened, and the face slopes downwards towards the breast at an acute angle with the top of the head. The thorax is wider than long, with the front margin curving forwards, the hind margin transverse, or not extended between the wing-covers, which space is filled by a pretty large triangular scutel or escutcheon. The wing-covers are generally opake, rather long and narrow, and more or less inclined at the sides of the body, not flat however, but moulded somewhat to the form of the body, and the wings are rather shorter and broader, not netted like those of the tree-hoppers, but strengthened by a few longitudinal veins. The eyes, which are distant from each other, and placed at the sides of the head, are pretty large, but flattish, and not globular as in the Cicadas; and the eyelets, which are rarely wanting, vary in their situation, being sometimes on the top and sometimes below the front edge of the head. Notwithstanding the small size of most of these insects, they are deserving our attention on account of their beauty, delicacy, and surprising agility, as well as for the injury sustained by vegetation from them.

It is stated by the late Mr. Fessenden, in the "New American Gardener," that some persons in this country have entirely "abandoned their grape-vines" in consequence of the depreda

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tions of a small insect, which, for many years, was supposed to be the vine-fretter of Europe. It is not, however, the same insect, but is a leaf-hopper, and was first described by me in the year 1831, in the eighth volume of the "Encyclopædia Americana," under the name of Tettigonia Vitis. In its perfect state it measures one tenth of an inch in length. It is of a pale yellow or straw color; there are two little red lines on the head; the back part of the thorax, the scutel, the base of the wing-covers, and a broad band across their middle, are scarlet; the tips of the wing-covers are blackish, and there are some little red lines between the broad band and the tips. The head is crescent-shaped above, and the eyelets are situated just below the ridge of the front. The vine-hoppers, as they may be called, inhabit the foreign and the native grapevines, on the under surface of the leaves of which they may be found during the greater part of the summer; for they pass through all their changes on the vines. They make their first appearance on the leaves in June, when they are very small and not provided with wings, being then in the larva state. During most of the time they remain perfectly quiet, with their beaks thrust into the leaves from which they derive their nourishment by suction. If disturbed, however, they leap from one leaf to another with great agility. As they increase in size they have occasion frequently to change their skins, and great numbers of their empty cast skins, of a white color, will be found, throughout the summer, adhering to the under sides of the leaves and upon the ground beneath the vines. When arrived at maturity, which generally occurs during the month of August, they are still more agile than before, making use of their delicate wings as well as their legs in their motions from place to place; and, when the leaves are agitated, they leap and fly from them in swarms, but soon alight and begin again their destructive operations. The infested leaves at length become yellow, sickly, and prematurely dry, and give to the vine at midsummer the aspect it naturally assumes on the approach of winter. But this is not the only injury arising

• Article Locust, p. 43.