CHAPTER VIII. 



THE PISH AND CHUSTACEANS OF THE AQUAEIUM. 



A MAEiNE Aquarmm may be rendered very interest- 

 ing without the introduction of fish, and as their 

 presence requires that the water should be once each 

 day aerated by means of additional water, introduced 

 by the syringe or by a drip, continuing for some 

 time from another vessel, many may prefer the 

 lovely Sea-Weeds, curious Zoophytes, and beautiful 

 Molluscs, alone ; as, if the balance between the 

 amount of animal and vegetable life be felicitously 

 balanced, and the natural scavengers, in the shape 

 of Periwinkles and other Sea-Snails, for the con- 

 sumption of decaying vegetable matter, and a few 

 Prawns to perform a similar of&ce for perishing In- 

 fusori(E^ or any other animal matter, be properly 

 supplied — the tank may remain for a long time un- 

 disturbed, the supply of oxygen being ample for the 

 lower classes of animal life alluded to. The beautiful 

 JctinicB^ indeed, will exist in apparent health for a 

 considerable time in water in which no vegetable 

 growth has been introduced. Mr. Gosse describes 



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