Among our long-legged gnats there is no one more singular in its appearance and graceful in its motions than the Ptychoptera clavipes, of Fabricius, or club-footed Ptychoptera. A new genus, called Bittacomorpha, on account of the fancied resemblance of this insect to the Neuropterous genus Bittacus, has lately been made for its reception, by Mr. Westwood.* This pretty gnat is of a black color, with a broad, white stripe on the face, a short, white line on the forepart of the thorax, and three broad, white rings on the legs. The sides of the thorax are silvery white, and the hind-body is dusky brown, with a narrow white line on the edges of each of the rings. The head is small, and almost hidden under the thick and hunched thorax; the antennæ are many-jointed, slender, and tapering; the hind-body is long, narrow, and somewhat flattened; the legs are very slender next to the body, and increase in thickness towards the end, and the first joint of the feet is swollen, oblong oval, and very downy. The length of the body is about half an inch, and the wings expand nearly three quarters of an inch. It appears in July, and takes wing by day. As it flies slowly along, it seems almost to tread the air, balancing itself horizontally with its long legs, which are stretched out, like rays, from the sides of its body.

There are exceptions to almost all general rules. Thus we find, among Dipterous insects, some kinds that never have wings. One of these is the thick-legged snow-gnat, or Chionea valga. This singular insect looks more like a spider than a gnat. Its body is rather less than one fourth of an inch long, and is of a brownish yellow or nankin color. The legs are rather paler, and are covered with short hairs. The head is small and hairy. The first two joints of the antennæ are thick, the others slender and tapering, and beset with hairs. Although the wings are wanting, there is a pale yellow poiser on each side of the hinder part of the thorax. The hindmost thighs are very thick, and somewhat bowed, in the males, which suggested the name of valga, or bowlegged, given to the insect in my "Catalogue." The body of the female ends with a sword-shaped borer, resembling that of a grasshopper. These wingless gnats live on the ground, and the

* "Philosophical Magazine," Vol. VI. p. 281. Lond. 1835.

females bore into it to lay their eggs. They are not common here. Mr. Gosse found considerable numbers of them in Canada, crawling on the snow, in pine woods, during the month of March.*

Travellers and new settlers, in some parts of New England and Canada, are very much molested by a small gnat, called the black fly (Simulium molestum), swarms of which fill the air during the month of June. Every bite that they make draws blood, and is followed by an inflammation and swelling which last several days. These little tormentors are of a black color; their wings are transparent; and their legs are short, and have a broad whitish ring around them. The length of their body rarely exceeds one tenth of an inch. They begin to appear in May, and continue about six weeks, after which they are no more seen. They are followed, however, by swarms of midges, or sand-flies (Simulium nocivum), called no-see-'em, by the Indians of Maine, on account of their minuteness. So small are they, that they would hardly be perceived, were it not for their wings, which are of a whitish color, mottled with black. Towards evening these winged atoms come forth, and creep under the clothes of the inhabitants, and by their bites, produce an intolerable irritation, and a momentary smarting, compared † to that caused by sparks of fire. They do not draw blood, and no swelling follows their attacks. They are most troublesome during the months of July and August.

The most common of our large gad-flies, or horse-flies, appears to be the Tabanus atratus, of Fabricius. It is of a black color, and the back is covered with a whitish bloom, like a plum. The eyes are very large, and almost meet on the top of the head; they are of a shining purple-black or bronzed black color, with at narrow deep black band across the middle, and a broad band of the same hue on the lower part. The body of this fly is seven eights of an inch or more in length, and the wings expand nearly two inches. The Tabanus cinctus, of Fabricius, or orangebelted horse-fly, is not so common, and is rather smaller. It is also black, except the first three rings of the hind-body, which

"Canadian Naturalist." p. 51. ↑ See Gosse's" Canadian Naturalist." p. 100.

are orange-colored. The most common of our smaller horse-flies is the Tabanus lineola, so named, by Fabricius, because it has a whitish line along the top of the hind-body. Besides these flies, we have several more kinds of Tabanus, some of which do not appear to have been described. These blood-thirsty insects begin to appear towards the end of June, and continue through the summer, sorely tormenting both horses and cattle with their sharp bites. Their proboscis, though not usually very long, is armed with six stiff, and exceedingly sharp needles, wherewith they easily pierce through the toughest hide. It is stated that they will not touch a horse whose back has been well washed with a strong decoction of walnut leaves. The eyes of these flies are very beautiful, and vary in their colors and markings in the different species.

The golden-eyed forest flies are also distinguished for the brilliancy of their spotted eyes, and for their clouded or banded wings. They are much smaller than the horse-flies, but resemble them in their habits. Some of them are entirely black (Chrysops ferrugatus, Fabricius), others are striped with black and yellow (Chrysops vittatus, Wiedemann). They frequent woods and thickets, in July and August.

The bee-flies, or Bombylians (BOMBYLIADE), have a very slender proboscis, sometimes exceeding the length of their body. They are met with in sunny paths in the woods, in April and May. They fly with great swiftness, stop suddenly every little while, and, balancing themselves with their long, horizontally spread wings, seem to hang suspended in the air. They often hover, in this way, over the early flowers, sucking out the honey thereof, like humming-birds, with their long bills. Our largest bee-fly is the Bombylius æqualis, so named by Fabricius, because the wings are divided lengthwise, in their color, into two equal parts, the outer part being brownish black, and the inner half colorless and transparent. The body of this insect is short, rounded, and covered with yellowish hairs, like a humblebee. It measures three eighths of an inch in length, and the wings expand rather more than seven eighths of an inch.

There are some flies that prey on other insects, catching them on the wing or on plants, and sucking out their juices. Some of

these rapacious flies are of great size. The largest one found here is the orange-banded Midas (Midas filatus *), specimens of which are sometimes found measuring an inch and a quarter in length, with wings expanding two inches and a quarter. It is black, with an orange-colored band on the second ring of the hind-body; and the wings are smoky brown, with a metallic lustre. It receives its scientific name, filatus, signifying threadlike, from its antennæ, which are long and slender, but they end with an oblong oval knob. Its generical name was also given to it on account of its long antennæ; Midas, in Mythology, being the name of a person fabled to have had the long ears of an ass. The orange-banded Midas may often be seen flying in the woods in July and August, or resting and basking in the sun upon fallen trees. Its transformations have never been described. Its larva and pupa almost exactly resemble those of the rapacious Asilians (ASILIDE). The larva is a cylindrical, whitish maggot, tapering before, and almost rounded behind; it has only two breathingholes, which are placed in the last ring but one; and it grows to the length of two inches. It lives and undergoes its transformations in decayed logs and stumps. The pupa measures about an inch and a quarter in length; it is of a brown color, and nearly cylindrical shape; its tail is forked; there are eight thorns on the forepart of its body; and each ring of the abdomen is edged with numerous sharp teeth, like a saw, all these teeth pointing backwards, except those on the back of the first ring, which are directed forwards. The pupa pushes itself half way out of the stump when the fly is about to come forth, and the latter makes its escape by splitting open the back of the pupa-skin.

In the month of June, there may sometimes be seen, resting on the grass or on rotten stumps, in open woods, a large, lightbrown or drab-colored fly, somewhat like a horse-fly in form, but easily distinguished therefrom by two little thorns on the hinder part of the thorax; and by the wings, which do not spread so much when the insect is at rest. It is heavy and sluggish in its motions, and does not attempt to fly away when approached. This insect was called Canomyia pallida, the pale Conomyia,

by Mr. Say, in the Appendix to Keating's "Narrative,” and in the second volume of the "American Entomology," where it is figured. The generical name, signifying a common fly, is rather unfortunate, for this is a rare insect. The only specimens known to Mr. Say were found by him in a small forest of scattered trees, on the Pecktannos river, in Wisconsin Territory. A few have been taken in Massachusetts, one of them on Blue Hill, in Milton; and Mr. Gosse found three specimens, in as many years, in Canada. In its transformations this insect is more nearly related to the gad-flies and the Asilians than to the soldier-flies, near which it has generally been placed; though it approaches the latter in its structure, and in its sluggish habits. The larvæ or maggots, though not yet discovered, undoubtedly live in the ground, or in decayed vegetable substances, like those of the horse-flies and other predatory insects; for Mr. Gosse found one of his specimens, on the grass, in the act of emerging from the pupa-skin. He has also figured the pupa, which is of a chestnut-brown color, and has transverse rows of spines on the abdominal rings.

*

Most of them are

Most of the soldier-flies (STRATIOMYADE) are armed with two thorns or sharp spines on the hinder part of the thorax. They form the first family of the flies that undergo their transformations within the hardened skin of the larva, which is not thrown off till they break through it to come out in the winged state. Their proboscis contains, at most, only four bristles, is not fitted for piercing, but ends with large fleshy lips, by means whereof these flies suck the sweet juices of flowers. found in wet places, where their larvæ live; some of the latter being provided with a tube, in the hinder extremity, which they thrust out of the water in order to breathe. The skin of these larvæ is merely shortened a little, without wholly losing its former shape, when the inclosed insects change to pupa; thereby showing that this family is truly intermediate between the preceding flies, which cast off their larva-skins, and those which retain them, and take an oblong oval shape, when they become pupæ. Some of the soldier-flies (Stratyomys) have a broad oval body, orna

* "Canadian Naturalist." p. 199.