FEESH-WATEK FISH AND MOLLUSCA. 61 



The Crawfish, or fresh-water Lobster, makes a strik- 

 ing addition to the tank. It is common in most streams, 

 and is well known and easily recognized. 



The Fresh-water Fish. Fish of every size may answer 

 for the Aquaria. Those of considerable magnitude re- 

 quire tanks of corresponding proportions, and such tanks 

 are too cumbrous and ungraceful for domestic use. We 

 shall chiefly confine ourselves, therefore, to the smaller 

 class of fish in these pages. 



The Pigmy Dace {Leuciscus 'pygmcms), is a pretty little 

 article, excellently well adapted to the Aquarium. He is 

 ornamented with a small black spot, margined with white, 

 on each side of the tail. In most of the brooks in this 

 and in the New England States he may be captured. 



The Black-nosed Dace is an active specimen, of good 

 habits and prepossessing appearance. He may be found 

 in nearly every clear stream and rivulet. 



The Tessellated Darter {Boleosoma tessellatum)^ is a 

 singular fish, of small size, and equally plentiful. In a 

 perfectly limpid stream you may observe him lying motion- 

 less at the bottom, as if asleep, when suddenly he will 

 spring towards his passing prey with marvellous velocity. 

 It is this practice that has bestowed upon him his name. 



The Spotted Troutlet {Baione fontinalis) is another 

 dwarf-fish, lively, handsome, graceful, and well behaved. 

 Nothing could be better fitted for a tank. 



Gold and Silver Fish everybody is familiar with, and 

 properly selected, they make very eligible denizens of the 



