CHAP. 52.—VARIOUS KINDS OF SHELL-FISH.

Let us now pass on to the murex[1] and various kinds of shellfish, which have a stronger shell, and in which Nature, in her sportive mood, has displayed a great variety-so many are the various hues of their tints, so numerous are their shapes, flat,[2] concave,[3] long,[4] crescent-shaped,[5] rounded into a globe, cut[6] 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,[7] or else folding inwards.[8] And then, too, there are the various dis- tinctions[9] of rayed shells, long-haired[10] shells, wavy-haired shells, channelled shells, pectinated shells, imbricated shells, reticulated shells, shells with lines oblique or rectilinear, thick-set shells, expanded shells, tortuous shells, shells the valves or which are united by one small knot, shells which are held together all along one side, shells which are open as if in the very act of applauding,[11] and shells which wind,[12] resembling a conch. The fish of this class, known as the shells of Venus,[13] are able to navigate the surface of the deep, and, presenting to the wind their concave side, catch the breeze, and sail along on the surface of the sea. Scallops are also able to leap[14] and fly above the surface of the water, and they sometimes employ their shell by way of a bark.

1. Univalves, with a thick spinous shell.

2. The flat shell-fish, for instance, according to Cuvier, of the genus patella, or lepas.

3. Other fish of the genus patella, only more concave; the haliotes, for instance.

4. Forming a prolonged cone, Cuvier says, like the cerites.

5. The mouth of which is shaped like a crescent; such as the helices, Cuvier says.

6. The nerites, Cuvier says, which are cut into two hemispheres.

7. Such as many of the whelks, Cuvier says.

8. The whelks that have the edge turned inwards, so that one lip appears to fold under the other.

9. As no two naturalists might probably agree as to the exact meaning of the terms here employed, it has been thought advisable to give the passage as it appears in the original: "Jam distinctione virgulata, crinita, crispa, cuniculatim, pectinatim divisa, imbricatim undata, cancellatim reticulata, in obliquum, in rectum expansa, densata, porrecta, sinuata, brevi nodo legatis, toto latere connexis, ad plausum apertis, ad buccinum recurvis."

10. In allusion, probably, to the streaks or lines drawn upon the exterior of the shell.

11. With the mouth wide open, like that of a person in the act of applauding.

12. By "ad buccinum recurvis," he probably alludes to a whelk, or fish with a turbinated shell, resembling the larger conch or trumpet shell, which Triton is sometimes described as blowing.

13. Probably some of the Cypræa; which have been already alluded to in Note 6 to c. 41 of the present Book. Cuvier remarks, that there are many of the univalve shell-fish that float on the surface of the water, but none, with the exception of the argonauta or nautilus, are known to employ a membranous sail.

14. Cuvier says, that he has been informed that the scallop, by suddenly bringing together the valves of its shell, is able to make a bound, and leap above the surface of the water.