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then raising them into the air and devouring them. Many other insects also aid in the work of destruction, and assist in checking the undue preponderance of Aphides by maintaining the balance of power.

It is the same with other insects. Smaller species of Anthomyia are also very destructive to vegetation; but dung flies, in their perfect state, devour them with greediness, seizing them with their fore-feet, piercing their heads and sucking the juices. Who shall determine the check which injurious insects receive from Ichneumons and Tachinæ, and such parasites?

In a paper published in the Proceedings of the Entomological Society of Philadelphia, Mr. Walsh directs attention to the number of species of insects which haunt one kind of willow-gall (Salicis brassicoides). In this, besides the Cecidomyia, which is the maker of the gall, he enumerates four other insects of the same genus, one saw-fly, five species of minute Lepidoptera, two or three beetles, a Psocus, a heteropterous insect, an Aphis, the larvæ of a Chrysopa, and a Syrphide, besides four or five species of Chalcididæ, one Ichneumon, and one of Techinidæ. Altogether about two dozen species, distributed through eight orders, and all dependent one upon another, and upon the fostering gall.

We have said enough to indicate the truth of Mr. Dallas's observation that "Nothing is more remarkable, or more conducive to show us the intricacy of the mechanism by which the balance of power is maintained in the economy of nature, than the circumstance that many of the species of these parasitic insects, whose duty is evidently that of keeping down the excessive increase of their vegetable-feeding brethren, are themselves kept in check by other species, which, by some infallible test, discover the concealed abode of their larvæ, and thus average the hapless victim upon whose substance they are remorselessly preying."

Kleptomania.—I had a good reason for disliking cats. When I was a boy they used to steal my young rabbits. We had a hole like a saw-pit, boarded and covered over with wooden bars, in which we kept, or rather tried to keep, our rabbits. One day, however, the gardener caught two cats working together at the theft, the thinnest getting down, and handing up the young rabbits to the accomplice. This was his account of the matter, and I can well believe it; for Argus—a red-eyed, evil-favoured Newfoundland we had—was once detected lamb-killing, then washing himself in a pond, and finally getting back to his kennel, and putting his head in the collar before he thought any of the household were up. There he was before our breakfast, with no evidence of guilt about him beyond the pleasant secret sense of early digestion begun in his own inside.—Jones' Holiday Papers.

There lives no greater pest to the wanderer and his horses and mules, than the Breeze-fly; by Breeze-fly I mean flies belonging to the genus Tabanus (order, Diptera, or two-winged), not those of the genus Œstrus, with which it is frequently confounded. The latter—commonly called Bot-fly, which is also a terrible pest, alike avoided by both horse and ruminant—deposits its eggs sometimes on the hair, and sometimes underneath the skin; hence animals, guided by a natural instinct, or having been the victims of a past and painful experience, all, at the sound of his dreaded trumpet, make the best of their way to the nearest water, into which they plunge.

On the contrary, in the Breeze-fly we have to do with a veritable blood-sucker more ravenous than would be any winged leech. There are three species, all three by far too plentiful for the comfort of either man or beat, and widely distributed in North-west America. These insects have an apparent ubiquity, and are literally everywhere. Ascend to the regions of eternal snow, there are hungry Breeze-flies awaiting one's arrival; by the rushing torrent, on the shores of the placid lake, under the deep, damp shadows of the pine-trees, or on the open flower-decked prairie, there are sure to be Breeze-flies. One barely hears the sound of its "clarion shrill" and hum of the rapidly-vibrating wings, ere one feels a sharp prick, as though a red-hot needle had been thrust into the flesh; stab follows stab in quick succession, and unless active measures of defence be resorted to, the skin speedily assumes the form of wire-gauze.

Your horses and mules, if you have any, give immediate notice of the enemy, by viciously throwing up their heads and heels, snorting, and, very possibly, indeed I may say generally, summarily discharging their loads, be they human or baggage, over their heads. Whether success attends this disagreeable habit or not, in any case a hasty retreat is made for the nearest water, where both man and beast well know the Breeze-fly seldom or never follows. I have frequently had a train of pack-mules completely scattered by these formidable pests.

The largest and fiercest is the Black Breeze-fly (Tabanus atratus). His body is like glossy black velvet, frosted over with a delicate white bloom, like a freshly-gathered Orleans plum; it is about an