364 METAZOAN PHYLA 



390. Remarkable Fishes.^ — Among the bony fishes are a number 

 remarkable for one reason or another. The smallest species, and also 

 the smallest of the vertebrates, is a Philippine goby, which does not 

 reach }'2 inch in length ; the largest of those which possess the usual form 

 attain a length of 15 to 20 feet; but one fish which is elongated, flat, and 

 bandlike in shape and is known as the oarfish, or the king of the herrings, 

 attains a length of 25 feet. The oarfish may be the basis of some stories 

 of sea serpents. The climbing perch of southeastern Asia climbs out 

 of the water on the roots and trunks of low trees for the purpose of 

 capturing food. The anterior spine of the dorsal fin of an angler fish is 

 greatly elongated and can be directed forward. At the end of this 

 spine and in a forward position of the spine in front of the mouth hangs 

 a fleshy, brightly colored bulb which in some species bears an interesting 

 resemblance to an animal upon which the fish feeds. In one type the 

 bulb at the tip is luminescent. This fish with the luminescent bulb was 

 described by Aristotle in the fourth century b.c. Ever since his time 

 these fish have been described as using the bulb as a lure to bring other 

 fishes within reach of its mouth, and to this these fish owe their name. 

 Some recent authorities, however, have doubted the validity of the 

 assumptions upon which rests this ancient zoological tradition. 



391. Economic Relations. — Fish are of great economic importance, 

 having from time immemorial been an important element in the food of 

 man. Not only are they themselves eaten as food, but the eggs of 

 certain ones, particularly Russian species of sturgeon, are eaten as 

 caviar. The flesh of some marine forms, however, is poisonous and 

 cannot be safely eaten. Some of the best known game fish are not 

 good for food, the tarpon, for example, being one of the most famous 

 and yet ordinarily not being eaten. 



Some fish are capable of inflicting a poisonous wound by means 

 of dorsal spines or a spiny operculum. Others are harmful because of 

 their destruction of the eggs, the young, or even the adults of food fish 

 and other valuable animals. 



Fish are more often cultivated in the Old World than in the New, 

 both for food and as pets. The Japanese have produced many curious 

 artificial varieties of the goldfish, originally a native of China. From 

 some fish is secured guanin, which in suspension in water is known as 

 pearl essence and which is used in the manufacture of artificial pearls. 



