Excerpt from British Fresh-Water Fishes Further: no satisfactory understanding of the fauna, or any class in the fauna, of any country can be had unless it is viewed in relation to that of the rest of the world. This is of special importance in dealing with fresh - water fishes, because, severely circumscribed by the limits of the medium in which they exist, the question constantly arises, How did such-and such a species get into certain rivers and not into others For example, the significance of the presence of the burbot in rivers running eastward in England, its absence from those running westward, cannot be appreciated unless the affinities of that fish are understood. When it is explained that the burbot is the only member of the great Cod Family known to inhabit fresh water, that it abounds in the rivers of Central and Northern Europe, as well as those of North America, a good deal of light is thrown upon the former connection of the streams Of Eastern England with the great watershed of the Rhine. Here, again, is the need for scientific as well as for popular names. The burbot is a cod, but the great Murray cod of Southern Australia is not a cod at all, but a perch. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.