THEIR ADVANTAGES. 229 



experiment, and thus the great ckcular course of 

 nature, the mutual dependence of organic life, he 

 imitated on a small scale. 



My ulterior ohject in this speculation was twofold. 

 First, I thought that the presence of the more delicate 

 sea-weeds (the Rhodosperms or red families especially 

 many of which are among the most elegant of plants 

 in colour and form), growing in water of crystalline 

 clearness in a large glass vase, would he a desirable 

 ornament in the parlour or drawing-room ; and that 

 the attractions of such an ohject would he enhanced 

 by the presence of the curious and often hrilliant-hued 

 animals, such as the rarer shelled Mollusca, the grace- 

 ful Nudihranchs, and the numerous species of Sea- 

 anemones, that are so seldom seen hy any one hut the 

 professed naturalist. 



But more prominent still was the anticipation that 

 hy this plan great facilities would he afforded for the 

 study of marine animals, under circumstances not 

 widely diverse from those of nature. If the curious 

 forms that stand on the threshold, so to speak, of 

 animal life, can he kept in a healthy state, under our 

 eye, in vessels where they can he watched from day to 

 day without being disturbed, and that for a sufficiently 

 prolonged period to allow of the development of the 

 various conditions of their existence, it seemed to me 

 that much insight into the functions and habits of 

 these creatures, into their embryology, metamorphoses, 

 and other peculiarities, might be gained, which other- 

 wise would either remain in obscurity, or be revealed 

 only by the wayward " fortune of the hour." 



Nor have these expectations been wholly unrealized. 



