A Marine Aquarium 



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failure. This will be evident when it is considered that the 

 temperature of the sea ranges only from about 40 0 to 65 0 . 

 Practically it is impossible to keep the temperature of private 

 aquaria within these limits, but by shading in hot weather, 

 and covering with wet cloths much may be done to keep down 

 excessive heat. The evolution of oxygen from plants is not 

 the only natural means by which the water can be main- 

 tained in a condition fit for the support of animal life. The 

 contact of the atmosphere with the water is an important 

 means to this end in the natural world, and it is essential 

 that in the aquarium the area of water surface should be large in 

 proportion to its depth. For this reason the earthen pan 

 suggested above is a more scientific vessel than the commonly 

 used bell glass which, as a rule, is too deep in proportion to 

 its breadth. 



The aquarium should be covered with a sheet of glass in 

 order to check loss by evaporation as well as to protect the 

 water from dust. This cover will not fit so closely as to 

 prevent the admission of air for surface oxygenation, and 

 there will still be a loss of water by evaporation. This must 

 be made good by the addition from time to time— and in 

 small quantities — of clear rain-water. 



The anemones will require to be fed by hand about once a 

 week. Small pieces of oyster or mussel must be placed on 

 the tentacles of each anemone, and if the animal be hun- 

 gry, the morsel will speedily be conveyed to the mouth in 

 the centre of the disc and will disappear. If it remains long 

 on the disc or is allowed to roll off it must be removed. 

 A pointed stick serves to adminster the food, and a dipping 

 tube of glass of rather less than half-an-inch diameter is 

 used for removing any uneaten or undigested morsels. If 

 particles of dead animal matter remain in the tank, the 

 water will lose its brightness, and an increased quantity of 

 oxygen must be forced in by means of the syringe already 

 referred to. 



Sibert Saunders. 



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