Zoological Illustrations Series II/Plate 84



That the system of nature is essentially a system of types and symbols, is a truth which has not only been perceived by philosophers, but is apparent to every attentive observer of nature. It has been our endeavour, in the second volume of Northern Zoology, to investigate this system, and to ascertain those laws by which it is regulated. One of the results of this enquiry has been, that every genus, pre-eminently typical, contains a greater number of forms than any other; the necessary consequence of comprising within itself, representations of every division in the whole family. By this test must our present definition of the typical genus Voluta be tried. We consider this particular species as the type of the whole group: according to Adanson, it is abundant on the western coast of Africa, where it is stated to vary considerably, both in its colour and in its plaits. To the same traveller we are indebted for the best account of the animal, which he describes under the name of L'Yet. It has been thought, indeed, that this is the Voluta neptuni, but as the interior of Adanson's L'Yet is "blanche" and that of Neptuni is yellowish orange, we rather think that the French writer intended to designate the Voluta cymbium of systematic authors.