454 THE AQUARIAN NATURALIST. 



" These islets on the living rock 



Are of a thousand shapes, 

 And Nature, with her various tints, 

 Diversifies their thousand forms : 



For some are green, like moss ; 

 Some ruddier tinged, or grey or silver white ; 

 And some, like yellow lichens, glow with gold : 

 Some sparkle sparry radiance to the sun, 



As gush their fountains up." 



These are COMPOUND ASCIDIANS, of which, for the 

 guidance of the young aquariist, we have figured one 

 or two examples (PL VIII. figs. 1 &2). A tangle, or 

 broad-leaved Fucus, torn from its rocky bed, or ga- 

 thered on the sands, where the waves have cast it 

 after a storm, will often show us similar bodies, mostly 

 star-figured, investing its stalks, winding among the 

 intricacies of its roots, or clothing, with a glairy coat, 

 the expanse of its foliated extremities. If some of 

 these gelatinous masses be removed alive in a vessel of 

 sea-water, and placed in our aquarium, we find them 

 lie there apparently as apathetic as sponges, giving few 

 signs of vitality beyond a slight pouting-out of sundry 

 tube-like membranes surrounding apertures which 

 slowly become visible on their surface. A closer and 

 more microscopic examination, however, teaches us 

 that they are by no means so inanimate as they ap- 

 pear, but that, at all the apertures above alluded to, 

 currents of water are in rapid motion : streams ejected 

 and whirlpools rushing in, indicate, that however torpid 

 these creatures may seem to ordinary observation, all 

 the machinery of life, respiratory wheels and circu- 

 latory pumps, are hard at work, concealed in their 

 inmost recesses. 



