LECTURE X. 147 



in size, though they frequently produce a numer- 

 ous offspring, being of a very prolific nature, and 

 viviparous. The young are produced of various 

 sizes, from that of a pin's head to that of half an 

 inch in diameter, and to the number of five, ten, or 

 more at a birth. As these animals are allied to the 

 Polype tribe in some degree, they partake of their 

 qualities, and will reproduce many of their organs, 

 when either purposely or accidentally mutilated. 



The minuter genera of the Mollusca it would 

 be tedious and uninteresting to particularize in 

 the course of a lecture, but the larger and more 

 remarkable ones justly demand our attention. Of 

 these the genus Asterias or Star-Fish is one of the 

 chief: it is rather of a coriaceous pr crustaceou 

 nature than of that soft cast so common to many 

 other of the Mollusca* The generic character 

 consists in having a depressed body, covered by a 

 coriaceous or tough integument, roughened by 

 very numerous small processes or tentacula. The 

 mouth is central, and situated beneath. By far 

 the greater number of the Sea-Stars pr Asteriae are 

 of a stellated or radiated shape ; several lengthen- 

 ed arms or limbs proceeding from the common, 

 body or central partj so that the animal represents 



