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128 whether as regards compact gracefulness of form, brilliancy and diversity of colours, or the elegance with which the different hues are arranged, harmonized, or contrasted. Perhaps the whole of the great Class of vertebrate animals which form the subject of this volume, cannot show a more perfect example of elegance and beauty than the Common Mackerel, whose history we shall now proceed to delineate in detail.

The distinguishing characters of the Mackerels proper are the following: The body is spindle-shaped, or swelling in the middle and gracefully tapering to each extremity; it is uniformly covered with small smooth scales, which do not extend to the fins. The extremity of the tail is furnished with two slight ridges on each side. There are two dorsals, remote from each other, the second of which, as well as the anal, is followed by a number of small triangular finlets; the caudal is high, narrow, and crescent-shaped. The gill-covers are not armed with either spines or denticulations; the gill-rays are seven; there is a single row of small conical teeth in each jaw.

Two, if not three species of this restricted genus are taken on the shores of Britain, of which the most abundant is the well-known and valuable Common Mackerel, (Scomber scomber, Linn.), to the beauty of which we have already alluded. It is about fifteen inches in length; the colour of the upper parts is of a brilliant green, varied with rich blue, and crossed by a great number of narrow black bands; these are