FISHES 151 



Note the large eyes of most species, which enable them to see in water 

 with great sharpness, but which would be useless to them out of water. There 

 are ears as well, but these are difficult to find in most fishes. 



The fish, being cold blooded, requires no special warm covering, but its 

 skin is meant to protect it from harm. Generally it has a covering of over- 

 lapping scales, of a horny or bony substance. These differ considerably in 

 form : some are square, others rounded on two sides (cod and haddock), 

 others almost circular (herring). They fit over one another, like a bird's 

 feathers, or the slates of a roof ; and to prevent water getting between them, 

 a coating of slime oozes out from beneath many of them, through pores in 

 the skin. 



There are some two hundred British salt and fresh water fish, but only 

 a few of the commoner ones can be dealt with in this chapter. 



Fresh-water Fishes. 



Many of our fresh-water fishes belong to the Carp family (Cyprinida). 

 These are known as " Coarse Fish." 



THE CARP (Cyprinus carpio) 



was introduced from the Continent before the fifteenth century. It is hardy 

 and prolific, having often more than 500,000 eggs in a single roe. 



It is a very hardy species, and will live to a great age. There are still 

 some very large specimens, for instance, in the fishponds at Emmanuel College, 

 Cambridge, said to have been placed there more than one hundred years ago. 

 The average weight up to six years is from 4 to 10 Ib. ; the record for the 

 largest fish is 24 Ib. It is a greenish bronze in colour, with scales which 

 have black margins ; there is a large barbel at the corner of the mouth, and a 

 small one on the upper jaw. 



It is a slow moving fish, feeding chiefly on vegetable matter, as well as 

 on larvae and worms. 



1. The Crucian Carp (Carassius vulgaris) is much smaller, and has no 

 barbels on the jaws. It rarely exceeds i^ Ib. in weight, and is a rather more 

 thickset fish than the former, with which it freely interbreeds. 



2. The Golden Carp (Goldfish) (Carassius auratus) is a universal favourite 

 with aquarium keepers. It is really a Chinese or Japanese fish, in its native 

 waters a dark brown in colour, but in a domesticated state losing the black 

 and brown pigment and becoming golden-yellow, and in some cases silver. 

 It was introduced into England in 1691. 



3. The Barbel (Barbus vulgaris) is very common in the Thames, and is 

 fond of muddy ponds. It grows to a great length, as much as 3 feet, and up 

 to 15 Ib. in weight. It obtains its food by rooting in the mud with its snout 

 like a pig, as well as by feeding on aquatic vegetation. The mouth is furnished 



