=Psylla Pyri.=--Some _Aphides_ have the power of leaping, like the leaf-hoppers, but they differ from those insects in having very large transparent upper wings, which cover the sides of the body like a steep roof. The genus embracing these insects, is called _Psylla_. One of the species was observed by Dr. Harris, upon a pear tree. They live by suction, and having gorged themselves, the juice runs down on the bark, producing a blackish color; young trees suffered excessively. As Dr. Phumb, of Salisbury, Conn., had observed them in 1833 on some imported pear trees, of which he lost several hundred in a few years, Dr. Harris suspected the insect to be the _Psylla pyri_, of Europe. Kollar recommends brushing off the insects, and crushing them under foot; and also advises to destroy the winged females in the spring. This being tedious and uncertain, it is recommended to wash the twigs with a brush, dipped in a mixture of strong soapsuds and flowers of sulphur, before the buds expand, to deter the insects from laying their eggs. A weaker solution, or the whale oil soap, might kill the young insects after they have fastened upon the bark, if applied with a syringe.[38] =Cicada septendecim=, or the Seventeen-year Locust, as it is erroneously called, is no Locust at all, but should be called _Cicada_, because, as already stated, when considering the order _Orthoptera_, the true Locusts, are, what we call Grasshoppers. This insect is remarkable for the long period of its pupal existence, which is subterranean, and during which it feeds upon the juices of roots. In its perfect state, it does not eat, and is neither able to bite nor to sting. The injury it does to our orchards is effected by its piercer in depositing its eggs, causing twigs to break and fall off. There are several Harvest-flies that belong to this order. =Tree Hoppers=, being members of the same order, feed upon the juices of plants, through their suckers, and are thus injurious; but their numbers are not sufficient to render them of much consequence. =Palæothrips mali=, (_Fitch_), is the name of an insect described by Dr. Fitch[39] as infesting apple trees in the month of August, where they were attacking the fruit. They excavated a little hollow near the blossom end of the apple about the size of a pea, which was occupied by small insects. Until the habits of the insect are more thoroughly understood, it will be difficult to advise any remedies. There is quite a number of insects in this class that affect the grape vine, some of which may become troublesome, and we should watch their habits. The following accounts are condensed from Dr. Fitch's Report: =Raphigaster sarpinus=, or the large Green Tree-bug, is grassy-green, edged with yellow, and a black point at every joint of the abdomen; found in September.