LECTURE X. 153 



high degree of contractile power, and are furnish- 

 ed at the extremity with a slightly expanded tip, 

 which acts as a sucker or fastener. By these feel- 

 ers also the Echinus takes its prey, fastening ea- 

 sily on any small shell-fish in its way, and securing 

 it, by applying to the shell the tips of its feelers 

 and dragging it to its mouth. This species is 

 considered as no unpleasant article of food, and 

 was a dish well known to the ancient Romans* 

 The internal structure of the spines, if closely ex- 

 amined, will be found to bear a considerable re- 

 semblance to those of the hedge-hog, the general 

 structure being the same in both, though the one 

 is of a horny, and the other of a calcareous sub- 

 stance. To particularize the Exotic Echini would 

 be an endless task. Among the most remarkable 

 species is the flattish-bodied Indian Echinus, with 

 extremely large, thick, club-shaped spines, of a 

 violet colour, barred with white. This curious 

 species, with several of its most remarkable va- 

 rieties, occurs in the highest perfection in the Le- 

 verian Museum. The shells of the Echini in ge- 

 neral, when dried, and divested of their spines, 

 generally present a very elegant and beautiful 

 appearance, the pattern of the jointed subdivisions 



