since as 1800, Dr. S. L. Mitchill, of New York, affirmed that the "insect is more formidable to us than would be an army of twenty thousand Hessians." In 1804, President Dwight, of Yale College, remarked that "this insect is feeble and helpless in the extreme, defenceless against the least enemy, and crushed by the most delicate touch; yet, for many years, it has taxed this country, annually, more, perhaps, than a million of dollars." At the present day, the amount of the injury inflicted probably far exceeds what it was forty years since; and to discover some feasible mode of exterminating the insect, or at least of arresting its ravages, is an object of great importance to this country.

Various remedial measures have, from time to time, been proposed; most of which I will here state.

1st. Steeping the seed wheat in elder juice, solution of nitre, boiling water, or other liquids; or rolling in lime, ashes, or some other substance, in order to kill the eggs. But as the eggs of the Hessian fly are not on the seed, they will never be hurt by such processes.

So far as these

means give vigor to the plant, they may be of some little service.

2d. Sowing seed obtained from places in which the insect has not made its appearance, (American Museum, iv, 47.) This recommendation also assumes the error, that the eggs are laid on the grain, and will be found, as it has often proved, useless as respects this insect.

3d. Abstaining rigidly throughout the whole grain-growing region of North America from planting wheat, rye, barley, or oats, for one, two, or three years, and thus to starve out the insect! This plan might be effectual, but would obviously involve some inconveniences.

4th. Manuring the land very highly, so that the plants will grow vigorously, and be sooner out of the way of the insect, and also better able to resist it. This proposal has some merit, but does nothing towards destroying the insect.

5th. Sowing some variety of bearded wheat, flint wheat, &c., supposed to have a harder and more solid stalk than common wheat, and better able to withstand the impression of the larvæ. A suggestion of some value, but, equally with 4th, leaves the insect unharmed.

6th. Fumigating the wheat field, and sprinkling the young wheat with infusion of elder and with other steeps. If successful, which is quite uncertain, it is plain that these measures are impracticable on a large scale. 7th. Sowing winter wheat very late in the autumn, so that the fly shall have mostly disappeared before the plants are large enough to be attacked. No doubt this plan is to some extent useful, but the wheat sown late is in great danger of perishing during the winter. The fly will of course attack it in the spring, yet one attack will do less damage than two.

8th. Sowing oats early in autumn on the intended wheat field. It is. supposed the fly will lay its eggs on the plant; then let them be ploughed in, and the wheat sown. The fly having nearly exhausted itself on the oats, the wheat will suffer less. This plan may possibly be of some partial utility.

9th. Drawing a heavy roller over the young wheat, both in autumn and spring. This process must be useful, in crushing many eggs and larvæ. 10th. Permitting sheep and other animals to graze the wheat fields while the insects are laying their eggs. By these means, large numbers of the eggs will be devoured with the leaves.

11th. Burning the stubble immediately after harvest, and ploughing in

the remains. This is by far the most practicable and effectual mode of exterminating the insect, or, at least, of checking its increase. In the stubble are many pupa of the fly, at this time completely in our power; if, in reaping, the stubble is left high, the fire would sweep rapidly over a field, and destroy nearly all these pupa; the few which escaped the fire would, by the plough, be buried so deep as to perish in the earth; mere ploughing in of the stubble must be highly useful. If the two recommendations last named were thoroughly put in practice over the whole country-not only upon wheat, but also on rye and barley, and any other plants attacked by the Hessian fly-the ravages of this insect would, in all probability, ere long, become scarcely worthy of notice.

It may not be improper, in this place, to state that the foregoing account of the habits of the Hessian fly is derived from my own long-continued observations, and that I have moreover endeavored to consult all the papers of any importance which have been published on the subject.

There are in the United States, besides the Hessian fly, several other insects which attack the wheat while in the field. Those persons who assert that the former lays its eggs on the grain in the spike or head, have undoubtedly mistaken for the Hessian fly some one of these other insects. The following brief notices of the more important of these enemies, I have abridged from the accounts comprised in Dr. T. W. Harris's "Treatise on some of the Insects of New England, which are Injurious to Vegetation," (Camb. 1842. 459 pages, 8vo.,) a work of great interest and value.

In it the inquirer will find a faithful digest of all the reliable information we have on the numerous insects which injure our plants, fruits, and trees; and, in addition, he will learn the means of defence, so far as any have been discovered. The book ought to be in the hands of every intelligent farmer and orchardist.

1. A grain moth, (Angoumois moth-alucita cerealella, Oliv.,) probably the same as described by Colonel Carter, in the Transactions of the American Philosophical Society, volume i, 1771; and by J. Lorain, in Mease's Archives of Useful Knowledge, volume ii, 1812. It is about threeeighths of an inch long when its wings are shut. The upper wings are of a light brown satin color and lustre, covering the body horizontally above, but drooping a little at the sides. The lower wings and the rest of the body are ash-colored. The moth lays her eggs usually on the young and tender grain in the field; each caterpillar from these eggs selects a single grain, burrows into it, and remains concealed, devouring the meal within. Subjecting the grain to a heat of 167° Fahr., for twelve hours, in an oven, will kill the insect.

2. The English wheat fly (tipula tritici, Kirby) is a small orangecolored two-winged gnat, which lays its eggs in the head of wheat while blossoming. The maggots from these eggs are without feet, tapering towards the head, at first perfectly transparent and colorless, but soon becoming orange-yellow; and when mature, are each about an eighth of an inch long. It is supposed they devour the pollen, and prevent the setting of the grain; the maggots fall from the spike to the earth, within which they undergo their final transformations. This insect (or one very

similar to it) has done much damage in the Northern States and in Canada for several years past; but no effectual mode of preventing the mischief, or of destroying the insect, appears to have been devised.

3. The wheat caterpillar.-This is a span worm of brownish color, with twelve feet-six near each end of the body. It feeds on the kernel in the milky state, and also devours the germinating end of the ripened grain. It is said to be found in the chaff when the grain is threshed. We have little certain knowledge concerning the parent insect or its transformations.

In addition to these three, there are probably other insects more or less injurious to our wheat crops. Much has been published in our journals relative to these depredators; yet their habits are imperfectly understood, and many of the accounts are confused and contradictory. It is greatly to be desired, that all who have the opportunity should endeavor to make careful observations, and communicate them to the public.

These observations must be accompanied by accurate descriptions of the insect under examination, and in its various stages; otherwise, most of the labor will be spent in vain.

No. 2.

Extracts from Dr. Harris's work.

ON INSECTS.

The wheat crops in England and Scotland often suffer severely from the depredations of the maggots of a very small gnat, called the wheat fly, or the cecidomyia tritici of Mr. Kirby. This insect seems to have been long known in England, as appears from the following extract from a letter, by Mr. Christopher Gullet, written in 1771, and published in the "Philosophical Transactions" for 1772: "What the farmers call the yellows in wheat, and which they consider as a kind of mildew, is, in fact, occasioned by a small yellow fly, with blue wings, about the size of a gnat. This blows in the ear of the corn, and produces a worm, almost invisible to the naked eye; but, being seen through a pocket microscope, it appears a large yellow maggot, of the color and gloss of amber, and is so prolific that I distinctly counted forty-one living yellow maggots in the husk of one single grain of wheat-a number sufficient to eat up and destroy the corn in a whole ear. One of those yellow flies laid at least eight or ten eggs, of an oblong shape, on my thumb, only while carrying by the wing across three or four ridges. In 1795, the history of this insect was investigated by Mr. Marsham;* and since that time Mr. Kirby,† Mr. Gorrie, and Mr Shirreff, have also turned their attention to it. The investigations of these gentlemen have become very interesting to us, on account of the recent appearance in our own country, and the extensive ravages, of an insect apparently identical with the European wheat fly. The following account of the latter will serve to show how far the European and American wheat flies agree in their essential characters and.

Transactions of the Linnean Society,” vol. iii, p. 142, and vol. iv, p. 224. + "Transactions of the Linnean Society," vol. iv, p. 230, and vol. v, p. 96. "Coudon's Magazine of Natural History," vol. ii, pp. 323 and 448.

in their habits." The European wheat fly somewhat resembles a musquito in form, but is very small, being only about one-tenth of an inch long. Its body is orange-colored. Its two wings are transparent, and changeable in color; they are narrow at the base, rounded at the tip, and are fringed with little hairs on the edges. Its long antennæ, or horns, consist, in the female, of twelve little bead-like joints, each encircled with minute hairs; those of the male will probably be found to have a greater number of joints. Towards the end of June, or when the wheat is in blossom, these flies appear in swarms in the wheat fields during the evening, at which time they are very active. The females generally lay their eggs before nine o'clock at night, thrusting them, by means of a long retractile tube in the end of their bodies, within the chaffy scales of the flowers, in clusters of from two to fifteen, or more. By day they remain at rest on the stems and leaves of the plants, where they are shaded from the heat of the sun. They continue to appear and lay their eggs throughout a period of thirty-nine days. The eggs are oblong, transparent, and of a pale buff color, and hatch in eight or ten days after they are laid. The young insects produced from them are little footless maggots, tapering towards the head, and blunt at the hinder extremity, with the rings of the body somewhat wrinkled and bulging at the sides. They are at first perfectly transparent and colorless, but soon take a deep yellow or orange color. They do not travel from one floret to another, but move in a wriggling manner, and by sudden jerks of the body, when disturbed. As many as forty-seven have been counted in a single floret. It is supposed that they live at first upon the pollen, and thereby prevent the fertilization of the grain. They are soon seen, however, to crowd around the lower part of the germ, and there appear to subsist on the matter destined to have formed the grain. The latter, in consequence of their depredations, becomes shrivelled and abortive; and, in some seasons, a considerable part of the crop is thereby rendered worthless. The maggots, when fully grown, are nearly one-eighth of an inch long. Mr. Marsham and Mr. Kirby found some of them changed to pupa within the ears of the wheat; and from these they obtained the fly early in September. The pupa, represented by them, is rather smaller than the full-grown maggot, of a brownish-yellow color, and of an oblong oval form, tapering at each end. The pupæ found in the ears were very few in number-scarcely one to fifty of the maggots. Hence Mr. Kirby supposes that the latter are not ordinarily transformed to flies before the spring. Towards the end of September, he carefully took off the skin of one of them, and found that the insect within still retained the maggot form, and conjectures that the pupa is not usually complete until the following spring. According to Mr. Gorrie, the maggots quit the ears of the wheat by the 1st of August, descend to the ground, and go into it to the depth of half an inch. That they remain here, unchanged, through the winter, and finish their transformations, and come out of the ground in the winged form in the spring, when the wheat is about to blossom, is rendered probable from the great number of the flies found by Mr. Shirreff, in the month of June, in all the fields where wheat had been raised

*See also my article on wheat insects in the "New England Farmer for March 31, 1841 xix, p. 306.

the year before. The increase of these flies is somewhat checked by the attacks of three different parasites, which have been described by Mr. Kirby.

An insect, resembling the foregoing in its destructive habits, and known, in its maggot form, by the name of the "grain worm," has been observed, for several years, in the Northern and Eastern parts of the United States, and in Canada. It seems, by some, to have been mistaken for the grain weevil, the Angoumois grain moth, and the Hessian fly; and its history has been so confounded with that of another insect, also called the grain worm in some parts of the country, that it is difficult to ascertain the amount of injury done by either of them alone. The wheat fly is said to have been first seen in America about the year 1828,* in the northern part of Vermont, and on the borders of Lower Canada. From these places its ravages have gradually extended, in various directions, from year to year. A considerable part of Upper Canada, of New York, New Hampshire, and of Massachusetts, have been visited by it; and, in 1834, it appeared in Maine, which it has traversed, in an easterly course, at the rate of twenty or thirty miles a year. The country over which it has spread has continued to suffer more or less from its alarming depredations, the loss by which has been found to vary from about one-tenth part to nearly the whole of the annual crop of wheat; nor has the insect entirely disappeared in any place till it has been starved out by a change of agriculture, or by the substitution of late-sown spring wheat for the other varieties of grain. Many communications on this destructive insect have appeared in "The Genesee Farmer," and in "The Cultivator," some of them written by the late Judge Buel, by whom, as well as by the editors of "The Yankee Farmer," rewards were offered for the discovery of the means to prevent its ravages. Premiums have also been proposed, for the same end, by the "Kennebec County Agricultural Society," in Maine, which were followed by the publication, in "The Maine Farmer," of three "essays on the grain worm," presented to that society. These essays were reprinted in the seventeenth volume of the "New England Farmer," wherein, as well as in some other volumes of the same work, several other articles on this insect may be found. From these sources, and more especially from some interesting letters wherewith I have been favored by a lady lately resident in Hopkinton, Hew Hampshire, the foregoing and following statements are chiefly derived. A continued series of observations, conducted with care, and with a due regard to dates, is still wanted, to complete the history of the various insects which are injurious to grain in this country. Could Mr. Herrick (who is so well qualified for the task) be induced to devote the necessary time and attention to this subject, we have reason to think that the interests of science and of agriculture would be greatly promoted thereby.

The American wheat insect, in its winged form, has not yet fallen under my notice. It is stated by Judge Buel, Mrs. Gage, and others, to agree exactly with the description of the European wheat fly, (cecidomyia tritici,) being a very small orange-colored gnat, with long slender legs, and two transparent wings, which reflect the tints of the rainbow. Immense

Judge Buel's report in "The Cultivator," vol. vi, page 26; and "New England Farmer,”. vol. ix, page 42. Mr. Jewett says that its first appearance in western Vermont occurred in 1820. (See "New England Farmer," vol. xix, page 301.)