Let us now pass on to the murex and other kinds of shell-fish, which have a stronger shell, and in which Nature, in her sportive mood, has displayed a great variety—so many are the hues of their tints, so numerous are their shapes, flat, concave, long, crescent-shaped, rounded into a globe, cut through into a semi-globe, arched in the back, smooth, rough, indented, streaked, the upper part spirally wreathed, the edge projecting in a sharp point, the edge wreathed outwards, or else folding inwards. And then, too, there are the various distinctions of rayed shells, long-haired shells, wavy-haired shells, channelled shells, pectinated shells, imbricated............