filaments or hairs in their tails. The March brown, (see fig. 8,) the various shades of duns, (see fig. 5, 6, and 7,) which I described to you on a former occasion; the green (see fig. 9 and 10,) and white May fly, the red spinner, (see fig. 11,) are all of the class ephemeræ. These flies are produced from larvæ which inhabit the water, which can both crawl and swim, and which generally live in holes they make in the bottom. They change their coats several times before they become nymphæ. They quit their skin on the surface of the water, but even after they are flies, they have another transformation to undergo before they are perfect animals fitted for generation. They make use of their wings only to fly to some dry bank, or trunk of a tree, where they gradually disencumber themselves of the whole of the outward habiliment they brought from the water, including their wings. They become lighter, more beautiful in colour, and then begin their sports in the sunshine-appearing like what might be imagined of spirits freed from the weight of their terrestrial covering. This last transmutation has been observed and fully described by some celebrated naturalists, in the case of the May flies, and one or two

The

other species, and it probably will be found a general circumstance attached to the class: I have often observed what appeared to me to be the cast-off skins of the small species of ephemeræ on the banks of rivers and floating in the water. The green ephemera, or May fly, lays her eggs sitting on the water, which instantly sink to the bottom: and most of the duns, or small slender-winged flies, do the same. gray or glossy-winged May fly, commonly called the gray drake, performs regular motions in the air above the water, rising and falling, and sitting, as it were, for a moment on the surface, and rising again, at which time she is said to deposit her eggs. To attempt to describe all the variety of ephemeræ, that sport on the surface of the water at different times of the day, throughout the year, would be quite an endless labour. Some of them appear to live only a few hours, and none of them, I believe, have their existence protracted to more than a few days. In spring and autumn a new variety of these flies sometimes appears every day, or even in different parts of the same day. Of the beetle, or colyoptera genus, there are many varieties fed on by fishes. These insects, which are distinguished, as you know, by four wings, two husky.

like shells above, and two slender and finer ones below, are bred from eggs, which they deposit in the ground, or in the excrement of animals, and which, producing larvæ in the usual way, are converted into beetles, and these larvæ themselves are good bait for fish. The brown beetle, or cockchaffer, the fern fly, and the gray beetle, which are abundant in the meadows in the summer, are often blown into the water, and are the most common insects of this kind eaten by fishes. Whether the ditisci and hydrophili, the water beetles, are ever eaten by trout, I know not, but it is most probable. These singular animals are most commonly found in stagnant waters; fitted for flying, swimming, diving, and walking, they are omnivorous, and usually fly from pool to pool in the evening. They deposit their eggs in the water, where their larvæ live, but which, to undergo transmutation into the beetle, migrate to the land. But there is hardly any insect that flies, including the wasp, the hornet, the bee, and the butterfly, that does not become at some time the prey of fishes. I have not, however, the knowledge, or if I had, have not the time, to go through the lists of these interesting little animals; but of the family of one of them I must speak-the ichneumons, that deposit