however, will have been fully attained, if this treatise, notwithstanding its many faults and imperfections, should be found to afford any facilities for the study of our native insects, and should lead to the discovery and general adoption of efficient means for checking their ravages.

APPENDIX.

T having been thought desirable, in consequence of the increased ravages of the "army-worm " during the past year (1861), to give a description and illustrations of it, although not specifically referred to in the original manuscript of the author of this treatise, the following account has been compiled from various authentic sources.

The army-worm (Fig. 274) is the larva of a night-flying moth, Leucania unipuncta, Haworth (Fig. 275). (Synonymes, L. extranea, Guénee; L. impuncta, Stephens.) The IMAGO "is very plain and unadorned in its appearance. The eye, on first glancing at it, only recognizes it as an ordinarylooking moth of a tarnished

yellowish drab-color, inclining to russet, with a small white dot. near the centre of its fore wings, and a dusky oblique stripe at their tips. On coming to look at it more particularly, we find it to be rather less than an inch long, to the end of its closed wings, or, if these are extended, it is about an inch and three quarters in width, different specimens varying somewhat in size. Its fore wings are sprinkled with blackish atoms, and a short distance forward of their hind edge they are crossed by a row of black dots, one on each of the veins. Outside of the middle of the wing this row of dots suddenly curves forward, and from this curve a dusky streak runs to the tip of the wing, the ground-color being more pale and clearer yellow along the outer side of this streak..

Nearly in the centre of the wing is a milk-white dot placed upon the mid-vein. This dot is surrounded more or less by a dusky cloud, and this duskiness is frequently extended forward upon the mid-vein to its base, forming a faint darker streak along the middle of the wing. Contiguous to this dot on its outer side may be discerned a roundish spot of a slightly paler yellow color than the ground, and a very short distance forward of this is a similar spot, but smaller, both these spots often showing a more tarnished centre. On the hind part of the wing the veins are marked by slender, whitish lines, and between their tips on the hind edge of the wing is a row of minute black dots. The hind wings are smoky brown, with a purplish gloss, and are nearly transparent, with the veins blackish. The fringe of both pairs of wings is pale yellowish, with a dusky band on the middle. On the under side, the wings are much more glossy and paler, opalescent whitish inwardly, and smoky gray toward their outer and hind sides, where they are also freckled with blackish atoms. The smoky color on the hind wings has on its anterior edge a row of short blackish lines, one on each of the veins, and in a line with them on the fore wings is a faint dusky band, becoming more distinct toward its outer end, or sometimes only represented by a dusky dot on the outer margin forward of the tips. The veins are whitish, and also the hind edge, on which is a row of black dots placed between the tips of the veins. The hind wings have also a blackish crescent-shaped spot a little forward of their centre. The abdomen or hind body is smoky gray above, and on its under side ash-gray, freckled with black scales, and usually showing a row of black dots along each side."

The LARVA, or "army-worm," varies considerably in color and size, owing to age and locality, but its characteristic markings are so constant, as to make it readily distinguished. As it appeared in New Hampshire and Massachusetts, it varied in length from less than one inch to one and three quarters, was of a dark gray, with three narrow yellowish stripes above, and a broader one of the same color or slightly darker on each side, thinly clothed with short hairs, which were longer and somewhat thicker on and about the head, the latter of a polished honey-yellow, with a net-work of fine dark brown lines, and a black line on the front like the letter V reversed. The following

* Dr. Asa Fitch, in "The Country Gentleman," Vol. XVIII. p. 66.

descriptions, with methods of destruction, most of which were tried with good success in the Eastern States, are taken from an "Essay" in the Ohio Agricultural Report for 1860, by Mr. J. Kirkpatrick, of Cleveland, Ohio.

"The caterpillar of the army-worm moth, when fully grown, measures from one and three fourths to two inches in length, - when well fed, the latter, and' is about as thick as a goose-quill; color a lighter or darker gray, two lateral stripes, the upper with a yellowish central line, the lower a reddish one; legs, sixteen, six true or pectoral, eight prolegs or abdominal, and two anal, at the extremity of the body; the head brownish, sometimes marbled, and shining; a few short hairs on the body and longer straggling ones on the head. The pupa is of a mahogany-brown color, nine lines in length, and tipped at the end with a short spine.'

The PUPA (Fig. 276) of the army-worm in the Eastern States is of the same color, but varies in size, being usually smaller, and the spine is double or cleft at the apex.

Fig. 276.

"When the army-worms are numerous, it is desirable to arrest their ravages; the most common, and probably the easiest, method of doing this is that commonly practised, ploughing a double furrow around the field, or across any part of a field that they are marching toward. It is necessary to have the steep side of the furrow next the unharmed crop, so that when the worm attempts to climb over, it may fall back into the furrow. Running the plough once in the furrow is not sufficient; twice and even three times is better, and it requires to be renewed if washed down by rains. If the soil is stiff or stony, the worms will climb over the steepest ridge; it is on light, friable soil only that the ridge will suffice to protect the field. The foothold of the worm must give way, thus rolling it back into the furrow. And even under the best conditions of soil it is best to have two furrows, one about the width of a row of corn from the other. The worms thus trapped should be destroyed either by fire or hogs; laying dry straw in the furrows and then setting fire to it is a good way, for by this means the soil of the furrow is made more friable, and of course efficient. Where, however, there is dry grass or grain near by, this is a dangerous method, as the fire may extend to the field, and do more harm than the army-worm could if let alone.

Thousands of army-worms may be easily destroyed in a meadow, by running a heavy iron roller over it. A very small pressure is sufficient to burst their skins, and the slightest injury of this kind will kill them. If the meadow or field is level, few worms can escape the roller, and thus a stop will be put to them at once. Of course this cannot succeed as well where the ground is rough and uneven, for the worms always take shelter in the hollows. The best time to roll is while the worms are feeding and up among the leaves, for then they are sure to be crushed; at other times they are sheltered, and a great number will escape. As soon as the crop is removed from an infested field, turn in all the hogs you can, and also chickens and turkeys; ducks will do a great deal of good by searching for and eating the caterpillars. All these animals will eat the fallen grain, and thus save it in making flesh and fowl. Sheep turned into the field will kill many of the worms by trampling upon them; especially will this be the case if the flock is large. If crows and blackbirds are visiting the fields, do not let them be disturbed; there never was a crow or blackbird, that would not prefer a fat caterpillar to a grain of corn, oats, or wheat."

Figures 277 and 278 represent two species of ichneumon which destroy great numbers of the army-worm. Several species of two-winged flies belonging to the Tachinada are also destructive to them. (See page 612; also, Plate VIII. Fig. 1.)