FISHES. 137 



place chosen for the partition is free from plants or rockwork. 

 None but large and rectangular aquaria should be thus 

 divided. 



The Perch is one of the most intelligent of all the fresh- 

 water fishes, soon learning to know its owner and its feeding 

 time. In a very little while it will become tame enough to 

 take food from the fingers. It is, however, rather nervous and 

 easily frightened while in captivity. Perch are found in 

 most of the rivers, canals, and lakes of Great Britain ; it is 

 somewhat rare in the North of Scotland. As these fish are 

 bold biters, they are not by any means difficult to catch ; but 

 unfortunately they are generally hooked in such a manner 

 that it is often a very difficult matter to free them without 

 seriously hurting them. The best way to procure Perch for 

 the aquarium is to catch them with a hand-net, according to 

 the directions given for taking roach ; for the young of the 

 former as well as of the latter during the autumn ascend 

 those streams which run into the rivers and canals where 

 these fish are found, and retire into the weeds and under 

 the banks. The fish thus caught will be of a suitable size 

 and free from injury. The Thames is noted for its very 

 beautiful Perch. Perch are able to live out of water almost 

 as long as the tench and the carp. They can be carried a 

 considerable distance by wrapping them up in wet grass or 

 moss. As Perch swim in shoals, two or three should be kept 

 together in the aquarium. 



Perch deposit their eggs during the latter part of April 

 and the beginning of May. The eggs are laid in strings or 

 ribbons, which are sometimes 4ft. or 5ft. long. These strings 

 of spawn are very interesting, the ova being placed closely 

 side by side in what appears to be a kind of tube. At first 

 sight it seems impossible that a fish the size of an ordinary 

 Perch could contain such a string of eggs ; but a closer 

 examination will show that what takes place in the case of 

 the spawn of frogs and toads is repeated in that of the 

 Perch. Each egg is surrounded by a membranous enve- 

 lope, which absorbs a great quantity of water as soon 

 as it is exuded from the fish. The ova are hatched in 



