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from the exhausting punctures of the vine-hoppers. In consequence of the interruption of the important functions of the leaves, the plant itself languishes, the stem does not increase in size, very little new wood is formed, or, in the language of the gardeners, the canes do not ripen well, the fruit is stunted and mildews, and, if the evil be allowed to go on unchecked, in a few years the vines become exhausted, barren, and worthless. In the autumn the vine-hoppers desert the vines, and retire for shelter during the coming winter beneath fallen leaves and among the decayed tufts and roots of grass, where they remain till the following spring, when they emerge from their winter-quarters, and in due time deposit their eggs upon the leaves of the vine, and then perish. As the vine-hoppers are much more hardy and more vivacious than the European vinefretters or plant-lice, the applications that have proved destructive to the latter are by no means so efficacious with the former. Fumigations with tobacco, beneath a movable tent placed over the trellisses, answer the purpose completely.* They require frequent repetition, and considerable care is necessary to prevent the escape and ensure the destruction of the insects; circumstances which render the discovery of some more expeditious method an object to those whose vineyards are extensive.
There is another little leaf-hopper that has been mistaken for a vine-fretter or Thrips, though never found upon the grapevine. It lives upon the leaves of rose-bushes, and is very injurious to them. In its perfect state it is rather less than three twentieths of an inch long. Its body is yellowish white, its wing-covers and wings are white and transparent, and its eyes, claws, and piercer brown. The male has two recurved appendages at the tip of its hind body. It may be called Tettigonia Rosa.t Swarms of these insects may be found, in various stages of growth, on the leaves of the rose-bush, through the greater part of summer, and even in winter upon
• See Fessenden's “New American Gardener,” p. 299, for a description of the tent and of the process of fumigation.
+ This insect may be the Cicada Rose of Linnæus, or Iassus Rose of Fabricius. It belongs to Dr. Fitch's genus Empoa, as also does Teltigonia Fabæ. The Tettigonia Vitis is an Erythroneura of the same author.
housed plants. Their numerous cast skins may be seen adhering to the lower side of the leaves. They pair and lay their eggs about the middle of June, and they probably live through the winter in the perfect state, concealed under fallen leaves and rubbish on the surface of the ground. Fumigations with tobacco, and the application of a solution of whale-oil soap in water with a syringe, are the best means for destroying these leaf-hoppers.
I have found that the Windsor bean, a variety of the Vicia Faba of Linnæus, is subject to the attacks of a species of leafhopper, particularly during dry seasons, and when cultivated in light soils. In the early part of summer the insects are so small and so light colored that they easily escape observation, and it is not till the beginning of July, when the beans are usually large enough to be gathered for the table, that the ravages of the insects lead to their discovery. A large proportion of the pods will then be found to be rough, and covered with little dark colored dots or scars, and many of them seem to be unusually spongy and not well filled. On opening these spongy pods, we find that the beans have not grown to their proper size, and if they are left on the plant they cease to enlarge. At the same time the leaves, pods, and stalks are more or less infested with little leaf-hoppers, not fully grown, and unprovided with wings. Usually between the end of July and the middle of August the insects come to their growth and acquire their wings; but the mischief at this time is finished, and the plants have suffered so much that all prospect of a second crop of beans, from new shoots produced after the old stems are cut down, is frustrated. These leafhoppers have the same agility in their motions, and apparently the same habits, as the vine-hoppers; but in the perfect state they are longer, more slender, and much more delicate. They are of a pale green color; the wing-covers and wings are transparent and colorless; and the last joint of the hind feet is bluish. The head, as seen from above, is crescent-shaped, and the two eyelets are situated on its front edge. The male has two long recurved feathery threads at the extremity of the body. The length of this species is rather more than one tenth, but less than three twentieths of an inch. It may be called Tettigonia Fabæ. Probably it passes the winter in the same way as the vine-hopper.
2. PLANT-LICE. (Aphidida.) The Aphidians, in which group we include the insects commonly known by the name of plant-lice, differ remarkably from all the foregoing in their appearance, their formation, and their manner of increase. Their bodies are very soft, and usually more or less oval. The females are often without wing-covers and wings; and the former, when they exist, do not differ in texture from the wings, but are usually much larger and more useful in flight. We may therefore cease to call these parts wing-covers, in all the remaining insects of this order, and apply to them the name of upper wings.
Some of the Aphidians have the power of leaping, like the leaf-hoppers, from which, however, they differ in having very large and transparent upper wings, which cover the sides of the body like a very steep roof; and their antennæ are pretty long and thread-like, and are tipped with two short bristles at the end. Both sexes, when arrived at maturity, are winged, and some of the females are provided with a kind of awl at the end of the body, very different, however, from the piercers of the foregoing insects. With this they prick the leaves in which they deposit their eggs, and the wounds thus made sometimes produce little excrescences or swellings on the plant. These leaping plant-lice belong to a genus called Psylla, which was the Greek name for a small jumping insect. They are by no means so prolific as the other plant-lice, for ordinarily they produce only one brood in the year. They live in groups, composed of about a dozen individuals each, upon the stems and leaves of plants, the juices of which they imbibe through their tubular beaks. The young are often covered with a substance resembling fine cotton arranged in flakes. This is the case with some which are found on the alder and birch in the spring of the year.
Within a few years, a kind of Psylla, before unknown here, has appeared upon pear-trees in the western parts of Connecticut and of Massachusetts, particularly in the valley of the Housatonic, and in the adjoining counties of Dutchess and Columbia in New York. It was first made known to me,
in December, 1848, by Dr. Ovid Plumb, of Salisbury, Connecticut, and it is the subject of a communication in the "American Agriculturist,” for January, 1849. Since that time, Dr. Plumb has favored me with additional observations, and an account of his experiments with various remedies, and, towards the end of July, 1851, a brief visit to Salisbury gave me an opportunity of seeing the insects in a living condition, and in the midst of their operations upon the trees. This Psylla, or jumping plant-louse, is one of the kinds whose young are naked, or not covered with a coat of cotton. In some of its forms it is found on pear-trees during most of the time from May to October; and probably two if not more broods are produced in the course of the summer. It was first observed by Dr. Plumb in the spring of 1833, on some imported peartrees, which had been set the year before. These trees, in the autumn after they were planted, wore an unhealthy aspect, and had patches of a blackish rust upon their branches. During the second summer, these trees died; and other trees, upon which the same rusty matter was found, proved to be infested with the same insects. Like the aphides, or plant-lice, these insects live by suction. By means of their suckers, which come from the lower side of the head near the breast, they puncture the bark of the twigs and small branches, and imbibe the sap. They soon gorge themselves to such a degree, that the fluid issues constantly from their bodies in drops, is thrown over the surface of the twigs, and, mingled with their more solid castings, defiles the bark, and gives it the blackish color above noticed. Swarms of flies and ants upon the trees are a sure indication of the presence of these sap-suckers, being attracted by the sweetish fluid thrown out by them. Young trees suffer excessively by the attacks of these insects, nor do old trees escape without injury from them. In consequence apparently of their ravages alone, Dr. Plumb lost several hundred pear-trees from 1834 to 1838 inclusive; his trees have continued to suffer, to some extent, from this cause since that time; and he informs me that the same destructive depredations have been observed in all the adjacent region. On the 23d of July, I saw these insects on the trees, some already provided with wings, and others advancing towards maturity. The young ones were of a dull orange yellow color. They were short, and were obtuse behind, and had little wing-scales on the sides of their bodies. The perfect, or winged individuals, were about one tenth of an inch long from the forehead to the tips of the closed wings. The front of the head was notched in the middle. The eyes were large and prominent. The head and thorax were brownish orange, and the hind body greenish. Their four ample wings were colorless and transparent, and were marked with a few dark veins. The body of the female is pointed at the end, and inclines to a reddish hue. The pear-tree, in Europe, is subject to the attacks of a similar insect, called Psylla Pyri, the pear-tree Psylla. The European species is said to vary in color at different ages, and in different seasons of the year, being of a dull crimson color, shaded with black in the spring, when it comes forth to lay its eggs. Not having seen any of our pear-tree Psylla in their spring dress, I cannot say whether they agree with those of Europe in being of the same crimson color at this season of the year. As, however, they do correspond very nearly in other respects to the descriptions given of the European species, and have precisely the same destructive habits, and as they were first detected upon imported pear-trees, I apprehend that they were introduced from abroad, and that they will prove to be the same species as the European Psylla Pyri. The following particulars, abridged from Köllar's “ Treatise," if confirmed by future observations, will serve to complete the history of the American insect. The European pear-tree Psylla comes forth from its winter retreat, provided with wings, as soon as the buds of fruit trees begin to expand. After pairing, the female lays her eggs in great numbers near each other on the young leaves and blossoms, or on the newly-formed fruit and shoots. The eggs are oblong, yellowish, and look somewhat like grains of pollen. The young insects hatched therefrom resemble wingless plant-lice, and are of a dark yellow color. They