THE FRESH-WATER AQUARIUM. 



15 



stagnant or constantly circulating, for many fish whose 

 habitat is running streams cannot maintain a healthy 

 existence in a pool of still water. There are, however, 

 some species which are not so particular, and make 

 themselves perfectly at home either in still or running 

 water. Among these is the Eel, and if young healthy 

 specimens be selected, they live for a great number of 

 years and give very little trouble. Those adopted should 

 be small specimens with a cir- 

 cumference about equal to that 



of an ordinary lead pencil. 



They may be obtained of the 



dealers under the name of 



Silver Eels, and their easy 



graceful movements will ob- 



tain for them much attention. 



They are exceedingly slow in 



attaining size, in which respect 



they differ considerably from 



Bream, which increase in size 



very rapidly. These latter may 



well be kept in a large aqua- 

 rium with still water, their ^ 



natural habitat being muddy ^a) ValUmeria ; (b) Anacharis. 



ponds and lakes and the placid 



deeps of sluggish rivers. Being very timid fish, some 

 dark shelter should be provided for them in which 

 to hide. Far more suitable, however, is the Common 

 Carp, which cannot be equalled for hardiness. Always 

 a favourite in aquaria, it is a fish that can be depended 

 upon. Small specimens are the best and most interesting, 

 more interesting than its relative the Golden Carp, which 

 is kept chiefly on account of its gay colours. Both the 



