This genus of Beetle, popularly known as Weevils, are destructive to fruit, as nuts, nectarines, and peaches, as well as to peas, etc. There are many species.

C. betuleti. Vine Weevil. Colour, steel-blue. Attacks the leaf, rolling it up as a nest for its eggs. The pear is liable to its attacks also. Appears in June and July.

The species of Curculio, which is more fatal in its attack than any other, is popularly known as the Plum-Weevil. We copy the following article on the subject, from the Fruits and Fruit Trees of America: -

"The Curculio, or Plum-Weevil, (Rhynchaenus Nenuphar,) is the uncompromising foe of all smooth-stone fruits. The cultivator of the Plum, the Nectarine, and the Apricot, in many parts of the country, after a flattering profusion of snowy blossoms and an abundant promise in the thickly set young crops of fruit, has the frequent mortification of seeing nearly all, or indeed, often the whole crop, fall from the trees when half or two-thirds grown.

"If he examines these falling fruits, he will perceive on the surface of each, not far from the stalk, a small semicircular scar. This star is the crescent-shaped insignia of that little Turk, the Curculio; an insect so small, as perhaps, to have escaped his observation for years, unless particularly drawn to it, but which nevertheless appropriates to himself the whole product of a tree, or an orchard of a thousand trees.

"The habits of this Curculio, or Plum-Weevil, are not yet fully and entirely ascertained. But careful observation has resulted in establishing the following points in its history.

"The Plum-Weevil is a small, dark brown beetle, with spots of white, yellow, and black. Its length is scarcely one-fifth of an inch. On its back are two black humps, and it is furnished with a pretty long, curved throat and snout, which, when it is at rest, is bent between the forelegs. It is also provided with two wings with which it (lies through the air. How far this insect flies is yet a disputed point, some cultivators affirming that it scarcely goes farther than a single tree, and others believing that it flies over a whole neighbourhood. Our own observation inclines us to the belief that this insect emigrates just in proportion as it finds in more or less abundance the tender fruit for depositing its eggs. Very rarely do we see more than one puncture in a plum, and, if the insects are abundant, the trees of a single spot will not afford a sufficient number for the purpose; then there is little doubt (as we have seen them flying through the air,) that the insect flies farther in search of a larger supply.

But usually, we think it remains nearly in the same neighbourhood, or migrates but slowly.

"About a week or two after the blossoms have fallen from the trees, if we examine the fruit of the plum in a district where this insect abounds, we shall find the small, newly formed fruit, beginning to be punctured by the proboscis of the Plum-Weevil. The insect is so small and shy, that unless we watch closely it is very likely to escape our notice. But if we strike or shake the tree suddenly, it will fall in considerable numbers on the ground, drawn up as if dead, and resembling a small raisin, or, perhaps more nearly, a ripe hemp seed. From the first of April until August, this insect may be found, though we think its depredations on fruit, and indeed its appearance in any quantity, is confined to the month of May in this climate. In places where it is very abundant, it also attacks to some extent the cherry, the peach, and even the apple.

"Early in July the punctured plums begin to fall rapidly from the tree. The egg deposited in each, at first invisible, has become a white grub or larva, which slowly eats its way towards the stone or pit. As soon as it reaches this point, the fruit falls to the ground. Here, if left undisturbed, the grub soon finds its way into the soil.

"There, according to most cultivators of fruit, and to our own observations, the grubs or larvae remain till the ensuing spring, when in their perfect form they again emerge as beetles and renew their ravages on the fruit. It is true that Harris, and some other naturalists, have proved that the insect does sometimes undergo its final transformation and emerge from the ground in twenty days, but we are inclined to the opinion that this only takes place with a small portion of the brood, which, perhaps, have penetrated but a very short distance below the surface of the soil. These making their appearance in midsummer, and finding no young fruit, deposit their eggs in the young branches of trees, etc. But it is undeniable that the season of the Plum-Weevil is early spring, and that most of the larva; which produce this annual swarm, remain in the soil during the whole period intervening since the fall of the previous year's fruit.

"There are several modes of destroying this troublesome insect. Before detailing them, we will again allude to the fact, that we have never known an instance of its being troublesome in a heavy soil. Almost always the complaint comes from portions of country where the soil is light and sandy. The explanation of this would seem to be that the compact nature of a clayey soil is not favourable to the passage or life of this insect, while the warm and easily permeable surface of sandy land nurses every insect through its tender larvae state. Plum trees growing in hard trodden court-yards, usually bear plentiful crops. Following these hints some persons have deterred the Plum-Weevil by paving beneath the trees; and we have lately seen a most successful experiment which consisted in spreading beneath the tree as far as the branches extended a mortar made of stiff clay about the thickness of two or three inches - which completely prevented the descent of the insect into the earth. This is quickly and easily applied, and may therefore be renewed every season until it is no longer found necessary.

"The other modes of destroying the Plum-Weevil are the following: -

1. "Shaking the tret and killing the beetles. Watch the young fruit, and you will perceive when the insect makes its appearance, by its punctures upon them. Spread some sheets under the tree, and strike the trunk pretty sharply several times with a wooden mallet. The insects will quickly fall, and should be killed immediately. This should be repeated daily for a week, or so long as the insects continue to make their appearance. Repeated trials have proved, beyond question, that this rather tedious mode is a very effectual one, if persisted in. Coops of chickens placed about under the trees at this 12 season will assist in destroying the insects.

2. Gathering the fruit and destroying the larvae. As the insect, in its larva; or grub form, is yet within the plums when they fall prematurely from the tree, it is a very obvious mode of exterminating the next year's brood to gather these fallen fruits, daily, and feed them to swine, boil, or otherwise destroy them. In our own garden, where several years ago we suffered by the Plum-Weevil, we have found that this practice, pursued for a couple of seasons, has been pretty effectual. Others have reported less favourably of it; but this, we think, arose from their trying it too short a time, in a soil and neighbourhood where the insect is very abundant, and where it consequently had sought extensively other kinds of fruit besides the plum.

"A more simple and easy way of covering the difficulty, where there is a plum orchard or enclosure, is that of turning in swine and fowls during the whole season, when the stung plums are dropping to the ground. The fruit, and the insects contained in it, will thus be devoured together. This is an excellent expedient for the farmer, who bestows his time grudgingly on the cares of the garden.

3. "The use of salt. A good deal of attention has lately been drawn to the use of common salt, as a remedy for the Curculio. Trials have been made with this substance in various parts of the country, where scarcely a ripe plum was formerly obtained, with the most complete success. On the other hand, some persons, after testing it, have pronounced it of no value. Our own experience is greatly in favour of its use. We believe that, properly applied, it is an effectual remedy against the Curculio, while it also promotes the growth of the tree, and keeps the soil in that state most congenial to its productiveness. The failures that have arisen in its use, have, doubtless, grown out of an imperfect application, either in regard to the quantity or the time of applying it.

"In the directions usually given, it seems only considered necessary to apply salt, pretty plentifully, at any season. It* the soil be thoroughly saturated with salt, it is probable that it would destroy insects therein, in any stage of their growth. But, though the plum tree seems fond of saline matter, (and one of the most successful experimenters applied strong fish brine, at the rate of three or four pails full to a tree of moderate size,) it must be confessed this is a somewhat dangerous mode, as the roots are forced to receive a large supply of so powerful an agent at once.

"The best method of applying salt against the Plum-Weevil is that of strewing it pretty thickly over the surface, when the punctured plums commence dropping. The surface of the ground should be made smooth and hard, and fine packing salt may then be evenly spread over it, as far as the branches extend, and about a fourth of an inch in depth. Should the weather be fine, this coat will last until the fruit infected has all fallen; should it be dissolved or carried oft' by showers, it must be replaced directly. The larvae or grubs of the Weevil, in this most tender state, emerging from the plum to enter the ground, will fall a prey to the effect of the salt before they are able to reach the soil. If this is carefully and generally practised, we have little doubt of its finally ridding the cultivator of this troublesome enemy, even in the worst districts and soils".