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overhanging trees and bushes, to which they adhere till they are hatched—a process which, in summer weather, soon takes place. The eggs produce little six-legged larvae, which fall into the water, and immediately set about constructing for themselves tube-like cases in which to reside secure from their numerous enemies—in the list of which are other larvae and fishes. When seen at the bottom of the water these cases appear like short bits of stick, but they will be found, on examination, to be regularly and beautifully constructed of various materials—some of minute portions of the leaves and other parts of aquatic plants; others of pieces of reed, grass, and the like; and many of fine gravel, sand, and even little shell fish, -each species selecting its peculiar materials, which are neatly and strongly cemented together with a kind of glue, which the larvae produce, and which completely resists the action of water. The cases are lined inside with a kind of silk, which the insect spins from its mouth in the same manner that caterpillars do. The cases of most species being specifically lighter than water, the larvae swim with facility, and thus have a greater range for their food than those species which inhabit cases composed of denser materials. These last are necessarily confined to the bottom for their food, and that, no doubt, is the particular place at which it can be found—the different species being of course led by instinct to select the proper and peculiar materials for their habitations. “Professor Rennie,” says a writer in the Saturday Magazine, “made repeated experiments with the larvae of the phryganidae, in order to ascertain their mode of building. He deprived them of their coverings, and furnished them with materials for constructing new ones. He found that they worked at first in a very clumsy manner—attaching with threads of silk a great number of chips to whatever materials were within their reach, and thus surrounding themselves with materials, many of which are never used in the perfect building. Unskilful as their efforts may at first appear, there is much wisdom in this aggregation of all the substances within their reach before their dwelling is actually commenced; for when these preparations are completed, they are able to devote their whole attention to the building, and to select the requisite materials from the heap close at hand.” The larvae feed principally on tender aquatic plants, but some species are carnivorous—preying on smaller insects, even of their own kind. Taken out of their cases, the larvae are often used as bait for trout and other fish. Their cases are open at each extremity, and when feeding or crawling they expose their head and legs, which are instantly withdrawn on the slightest alarm, and their hinder parts are furnished with two hooklike appendages, with which they are attached to their cases, and thus can draw them along as a snail does its shell. After having passed sufficient time in the larva state to arrive at the proper degree of maturity, the insect fastens its case to the stem of some water plant, or other substance, and, closing it at each extremity with a kind of grating, through which the water necessary for respiration flows, it turns to an inactive pupa, which is a further step towards its perfect state, the rudiments of which, indeed, now become clearly perceptible. In a few days it issues from its outer case, rises to the surface of the water, and, bursting its pupa skin, appears in its last and perfect form of a beautiful fly. The time at which this class of flies appears on the water depends on the temperature of the season. If it be mild, the sand fly will be seen in the end of March. This fly is much more abundant on some rivers than on others, and its E
imitation is more or less used in these different localities.* Bainbridge, Ronalds, and some other writers, speak highly of its “killing” properties. As the season advances the phryganidae appear only in the mornings and evenings; and in the height of summer, during the night only,– thus approximating to moths in their habits as well as conformation. The grannam, which is also called the green tail, from the colour of the bag of eggs in the female, first appears in April, and may be seen flitting, in infinite numbers, about the sides of the stream, and among the bushes on its banks. In warm weather during May and June, the angler should be at work by sunrise, for he will find the fish disposed for early breakfast on the grannams and other flies which sol's first beams bring into existence; and, as the summer advances, he may expect the fish to be more inclined for their winged feast at daybreak, and in the “shades of evening,” than during the heat and lassitude of the day. The male grannam is called the hare's flax, and is not, of course, in possession of the green caudal appendage of the female. The cinnamon fly, of which there are several varieties, comes on the water in August. It much resembles the sand fly of April. The family Ephemeridae comprises a tribe of insects very different in their appearance and habits from the phryganidae already described. Their antennae, or feelers, are very small, and their wings — which, in the smaller species, are very delicate and nearly transparent — stand erect on their backs, like those of the butterfly. They have two pairs of wings, the hindermost of which is very much smaller than the anterior pair. Their bodies are soft, small, and elongated, and from their extremity proceed two (in a few species three) long hair-like filaments, called Seta, or, in less scientific language, tails, or whisks. The ephemeridae, in their perfect state, are the most short lived of insects—hence their name. Their longest life extends but to a few hours; some species to only a few minutes. In the boxes of naturalists, however, they have been kept alive for more than ten days, but, as Mr. Westwood remarks, “there can be no doubt that had these individuals been at large and capable of pursuing their natural habits, their existence would have been as short as that of their companions.”
* Careful and complete instructions for dressing the various flies mentioned here and elsewhere in this work, and lists of the proper materials for the purpose, will be found in subsequent chapters.