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The scales or outward covering of fish are formed with surprising beauty and regularity; and in endless variety, in figure and texture; some are long, some round, some triangular, some square, and some or other of all shapes we can well imagine; some again are armed with sharp prickles, and some have smooth edges; and indeed, for variety, beauty, regularity, and order of arrangement, they bear a near resemblance to the wings of moths and butterflies.

It is generally believed, that an eel has no scales; but if its slime be wiped clean away, and the skin be examined with the microscope, it will be found covered with exceeding small scales, ranged in a very orderly manner, and I believe very few fish, unless they have shells, are without scales.

The farina of flowers, is that fine mealy powder which is found on the little pendant. tops of almost every flower its colour is different in flowers of different kinds. It was formerly imagined to be a mere excrementitious and unnecessary part of the plant; but the microscope has discovered, that all the minute grains of this powder, are regular, uniform, beautiful bodies, constantly of the same figure and size, in plants of the same species, but in different kinds of plants, are as different as the plants themselves.

The seeds of plants provide an ample field for the employment of the microscope; the ancients imagined the capillary plants, and many other kinds, produced no seeds, and

their mistake could never have been rectified by the naked eye; but the microscope has shewn, that the several species of fern, hartstongue, maidenhair, &c. are so far from being barren, that they are amazingly fruitful; that the seed vessels are on the backs of the leaves, and that the dust which flies off when we meddle with them, is nothing but their minute seeds. These seed vessels appear to the naked eye like a black or brown scurf on the back side of the leaf; but when veiwed by the microscope, they resemble little circular tubes, divided into many cells, containing seeds. When the seed is ripe, the vessels fly open with a spring, and spirt the seeds out on every side, in the form of dust; and if at that season, some of the leaves are put in a paper cone, and that be held to the ear, the seed vessels may be heard to burst, with a considerable noise; some of these minute vessels, contain at least one hundred seeds, invisible to the naked eye.

The dust of the fungus pulverulentus, or puffball, seems to the naked eye like smoke

or vapour; but when magnified by one of the greatest magnifiers, (for else it cannot be distinguished), it appears to be an infinite number of little globules, of an orange colour, somewhat transparent, whose diameter is not more than the fiftieth part of that of a hair.

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A-The Wolf, in its reptile state. B-Its appearance when transformed into a Moth.

The Weevil and Wolf are two kinds of insects which do abundance of mischief to many sorts of grain, by eating into them, and devouring all their substance; and as the account of them may be of some advantage to the farmer, we shall publish it at large.

The Weavil is somewhat bigger than a large louse, with two pretty, jointed, tufted, horns, and a trunk, or piercer, with which it gnaws its way into the heart of the grain, either to seek for food, or deposit its eggs there.

By keeping these creatures in glass tubes, with some grains of wheat, it will be found that the female perforates a grain, and therein deposits a single oblong egg, or two at most, (a grain of wheat being unable to maintain above one or two of the young brood when hatched) and this she does to five or six grains every day, for several days together. These eggs, not above the size of a grain of sand, in about seven days produce an odd sort of white maggot, which wriggles its body pretty much, but is scarcely able to move from place to place, as indeed it has no occasion, being happily lodged by its parents where it has food enough. This maggot turns into an aurelia, which in about fourteen days, comes out a perfect weevil.

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