46 



THE GOLDFISH AND ITS CULTURE. 



carpenter lays shingles on a roof, being disposed in such a way 

 that the friction incident upon the movement of the fish in the 

 water is reduced to the smallest proprotion. As the fish grows 

 older and larger the scales increase in size. 



Near the middle of the body and running along eacn side of the 

 fish, there is a line or row of scales that possess peculiarities distin- 

 guishing them from other scales. 



The.se scales are pierced with a tubular aperture, and the tubes of 

 which they are the exit are quite distinct, and form the so-called 



"lateral line." Through these 

 tubes a slimy substance or mu. 

 cous is exuded, which covers the 

 entire body, seemingly for the 

 purpose of making the fish water- 

 proof and of further reducing the 

 friction in the water. These 

 tubes always point from the m. - 

 SCALE FROM LATERAL LINE. {Enlarged.) trix, or root of the scale, towards 

 the tail of the fish. It is scales of this description that naturalists 

 refer to when seeking to learn the species to which the fish belongs, 

 because the peculiarities of their structure differ in them. (See 

 illustration.) 



The next thing most noticeable are the Jins, these being named 

 according to their location upon the body of the fish and subserve 

 various purposes. The />ec^oral fins (fig. a.) ar^ those situated in the 

 place corresponding with the fore-legs of animals, the ventral fins 

 (fig. b.) being placed where the hind-legs of animals are found. 

 The dorsal fin (fig. c.) is that one found upon the back of the fish. 

 That fin situated behind the anus receives its name from that part, 

 and is known as the anal fin (fig d.), while the tail of a fish is prop- 

 erly called the caudal fin, (fig. e.) 



