BIVALVE MOLLUSC A. 405 



species of these bivalves for representation. Spondylus regius 

 (Fig. L, PLATE XIX.) is, perhaps, the most remarkable for its immense 

 spines. Spondylus radians, Lamarck (Fig. III.), is noted for its 

 elegant form. Spondylus avicularis (Fig. IV.) shows remarkable 

 inequality in the valves. Spondylus iinperialis, Chenu (Fig. II.), has 

 long projecting spines, like feet; and the Scaly Spondylus (S. crassis- 

 qiiama, Fig. V.) is covered with scales arranged like so many roofing- 

 tiles. 



Like Ostrea, the genus Spondylus is frequently found firmly rooted 



Fig. 177. Pecten plica (Linnaeus). Fig. 178. Pecten japonica (Gmellin). 



to rocks and other submarine bodies, and, often er still, heaped one 

 upon the other, like herrings in their barrel. 



These animals belong essentially to the seas of warm countries. 

 We find them, however, occupying considerable space in the 

 Mediterranean, where the S. gcederopus (Fig. VI.) abounds. 



But the most remarkable species of all is assuredly Spondylus 

 regius (Fig. L, PLATE XIX.) This species is a native of the Indian 

 Ocean, and at one time there scarcely existed three fragments of 

 this rare shell in the museums of Europe. M. Chenu relates in one 

 of his books an anecdote which would prove if any proof were 

 necessary how far the desire of a collector to obtain possession of 

 some rare and costly specimen will carry him in order to attain his 



object. "M. R ," says M. Chenu, "was Professor of Botany to 



the Faculty of Paris, and was, as sometimes happens, more learned 

 than rich ; he wished, on the invitation of a stranger, to purchase 

 one of these shells at a very high price, which might be from 3,000 



