264 SUITABLE PLANTS. 



tive appearance, they will not live long in captivity ; 

 they presently begin to decay, and slough off in slimy 

 memhranous shreds, filthy to look at, and hurtful to 

 the living creatures. The Fuci live pretty well, but 

 their sliminess and ugliness are fatal to their preten- 

 sions. From the Eed and the Green Orders we must 

 make our selection. 



Of the former these will be found good. Rhyti- 

 phlcBa pinastroides, the Poiysiphonice, Corallina offici- 

 nalis, Delesseria alata, Ghondrus crispus, Phyllaphora 

 rubens (this, especially when dredged from deep water, 

 is one of the very best), the Griffithsim, and some of 

 the Callithamnia. 



Of the Green weeds Codium tomentosum does pretty 

 well, and affords food for some MoUusca that will eat 

 nothing else. The GladophorcB are good ; Bryopsis 

 plumosa, a most elegant little plant, flourishes in con- 

 finement; and Ulva laiissima is probably the best 

 of all sea-weeds for our purpose, and is one of the 

 most easily procured on every shore. 



The pieces of rook to which the plants are attached 

 should be as clean as possible. All adhering sponges, 

 in particular, should be carefully scraped off, unless 

 they are wanted for immediate examination ; as they 

 are sure to die, and corrupt the soil and water with 

 sulphuretted hydrogen, a most nauseous and noxious 

 gas, which turns everything black with which it comes 

 into contact. 



Animals. — Of the animals which thrive best in an 

 Aquarium (speaking, of course, only from my own 

 limited experience and observation) the following may 

 be mentioned. The small Sticklebacks (Gasterosteus), 



