86 THE COMPLETE ANGLER. 



It will be seen that there are about fifty species of fresh -water 

 fish which the angler may catch with a rod and line ; many, how- 

 ever, are rare, and need only be mentioned incidentally. 



It is needless to observe that fishes live in water ; but there are 

 still many who do not know that fishes breathe air, as will be seen 

 by the following sketch of their structure and habits. 



On each side of the neck you will observe bony plates of an 

 arch-like shape, to which pouch fringes are attached : these are the 

 gills, by which fish breathe. The water passes in at the mouth and 

 out at the gills ; but in its passage it impinges against the fringes, 

 which consist of innumerable blood-vessels, and by this means the 

 oxygen in the water is filtered and conveyed to the lungs of the fish. 



Fishes are enabled to float by means of an air-bladder in their 

 interior. Some species, however, do not possess this apparatus; 

 but as they are nearly of the same specific gravity as the water, the 

 want of this air-bladder may be no great inconvenience. They are 

 propelled through the water by means of the tail, and assisted and 

 balanced by the fins. 



The fins on either side of the breast are called the pectoral fins ; 

 those on the back dorsal fins \ on the belly ventral fins ; that behind 

 the vent the aural fin, and the tail the caudal fin. 



The teeth are placed in various portions of the mouth and throat, 

 according to the necessities of the species. 



The scales, with which fish are covered as with armour, are very 

 beautiful objects under the microscope. 



The temperature of fishes is, as a rule, very little above that of 

 the water they inhabit. 



Fishes have keen sight, fair hearing powers, small taste, acute 

 smell, and very little feeling or sensitiveness to pain. There are 

 numerous instances on record of the indifference fish appear to 

 have to injuries which would cause great pain to animals of a higher 

 organization. 



Finally, fishes lay eggs (spawn) on weeds, or in furrows in the 

 gravel, which are covered over, and remain until they are hatched 

 in due course. The male fish has the milt, or soft roe, and the 



