428 pliky's natural history. [Look IX. 



eyes/^ and have, therefore, to feel their way, by means of 

 these horns. 



(33.) Sea-scallops^^ are considered to belong to the same 

 class, which also conceal themselves during severe frosts and 

 great heats ; the onyches,^*^ too, which shine in the dai'k like 

 tire, and in the mouth even while being eaten. 



CHAP. 52. VARIOUS KINDS OF SHELL-FISH. 



Let us now pass on to the murex^^ and various kinds of shell- 

 fish, which have a stronger shell, and in which Nature, in her 

 sportive mood, has displayed a great variety — so many axe 

 the various hues of their tints, so numerous are their shapes, 

 tiat,^^ 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 dis- 



^* It is now known, thanks to the research of Swammerdam, that the 

 black points at the extremity of the great horns of the land snail, or Helix 

 terrestris, and at the base of them in the water snail, are eyes. 



^5 "Pectines in mari;" literally, "sea-combs." The French still call 

 them by a similar name, " peignes." They are known also in France as 

 "coquilles de St, Jaques," or St. James's shells ; probably, because worn 

 by pilgrims who had visited the shrine of St. Jago, at Compostella. In- 

 deed, the scallop shell was a favourite emblem with the palmers and pil- 

 grims of the middle ages, who were in the habit of wearing it on their 

 return in the hat. 



^^ He Latinizes the Greek name, calling it " unguis " — " a nail ;" and, 

 according to Varro, they were so called from their resemblance to the hu- 

 man nail. Pliny mentions them again in c. 87 of this Book, and in B. 

 xxxii. c. 53, where he states that they are also called "dactyli," or "fin- 

 gers." Cuvier says, that imdcr this name are meant the pholades, a bi- 

 valve shell-fish, which give forth a very brilliant light. 



^'' Univalves, with a thick spinous shell. 



^^ The flat sheU-fish, for instance, according to Cuvier, of the genus 

 patella, or lepas. 



99 Other fish of the genus patella, only more concave ; the haliotes, for 

 instance, 



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



2 The mouth of which is shaped like a crescent ; such as the helices, 

 Cuvier says. 



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

 •* Such as many of the whelks, Cuvier says. 



5 The whelks that have the edge turned inwards, so that one lip appears 

 to fold under the other. 



