198 THE AQUARIAN NATURALIST. 



These singularly formed larva (for such they are) 

 are to be found abundantly during the months of 

 August and September, sometimes crowding the sur- 

 face of the sea in rich profusion, swimming freely 

 about by the aid of rows of cilia, with which their 

 arms and the apex of their bodies are plentifully 

 furnished. 



The first appearance that presents itself indicating 

 the commencement of metamorphosis, is the develop- 

 ment of a number of projections around the stomach 

 of the Pluteus, which soon increase so much in number 

 that they form a series of rows surrounding the 

 stomachal cavity. At first these projections do not 

 extend beyond the body of the Pluteus, remaining, as 

 it were, concealed beneath its disc; but soon acqui- 

 ring greater development, they make their appear- 

 ance externally, and begin to assume some regularity 

 of arrangement, in which the rudimentary form of 

 the future star-fish begins to be perceptible, and the 

 points whence the arms are to proceed become ap- 

 parent. 



In carrying out this part of the proceeding, it will 

 be observed that the original arms or processes of the 

 Pluteus have had no share. The Pluteus, in fact, 

 stands just in the same relation to the young Ophiurus 

 as the frame does to a piece of embroidery. Neither 

 has the structure of its arms anything in common 

 with that of the rays of the future star-fish, which 

 lies, as it were, protected by their shelter. 



In the condition which it has now attained, the 

 young Ophiurus is much smaller than the rest of the 

 Pluteus ; but as its growth increases from this point, 



