110 



NERITA OF ARISTOTLE. 



of the tongue, a long rasp-like ribbon-shaped 

 organ studded with silicious teeth, that the car- 

 nivorous univalves perforate other shells and 

 destroy the included animals. The Purpura, 

 he says, dislikes rain, — a remark true of all 

 the marine gasteropods which live along the 

 coast line. 



In the Nerita (vvpirtig) of Aristotle we recog- 

 nise the literal forms of Trochus, so abundant 

 along the rocky shores of the JEgean. His 

 description of it as a large round smooth shell, 

 with a short spire, and round operculum, living 

 on rocks, puts the identification beyond a doubt. 

 Only one species of the modern genus Nerita 

 is found in the iEgean, the Nerita viridis, which 

 lives on the leaves of Caulerpa and other 

 green marine plants. It is local, small, and 

 evidently not the shell-fish so called by the 

 ancients. Aristotle compares the v^itvq with 

 the Kripvx, remarking the general resemblance 

 of the two shells in form, but distinguishes 

 the latter as spiny. This evidently indicates 

 another common iEgean shell-fish, the Turbo 

 rugosus, a conspicuous species, which could not 

 fail often to have come under his notice. He 

 distinguishes not only between the shells, but 



