394 



COLLEGE ZOOLOGY 



game fishes are the yellow perch, various 

 species of trout, pilces, muskellunge, and bass 

 (Fig. 252). Marine game fish include the 

 tarpon (Fig. 266), sea bass, and tuna. 



Marine food fish are of great value. Her- 

 ring (Fig. 266), in vast quantities, are 

 smoked, salted, pickled, and packed as 

 sardines. Mackerel are caught in enormous 

 numbers. The flounder family (Fig. 262) 

 contains halibuts, soles, plaice, and turbots. 

 Codfish (Fig. 266) is especially valuable, 

 together with other members of its family 

 such as pollacks, haddocks, and hakes. The 

 average annual catch of codfish is over two 

 billion pounds. Cod-liver oil is also the prin- 

 cipal source of vitamin A and vitamin D. 

 Rivaling the codfish in value are the salmon 

 of the Pacific Coast, which are caught and 

 canned in large quantities. In fresh water, 

 live whitefish, lake trout, catfish and perch- 

 all important food fishes. The eggs of stur- 

 geons and certain other fishes are made into 

 caviar, especially in Russia. The use of fish 

 meal has become important in the fertilizer 

 and pet-food industries. 



Fishing is becoming increasingly popular 

 as a recreation for millions of people. In one 

 midwest state alone over a million fishing 

 licenses are sold each year. The money spent 

 by fishermen in pursuing their sport runs 

 into manv millions of dollars. Enormous 

 sums are spent by the federal and state gov- 

 ernments in rearing fish and in stream and 

 lake improvement work. 



Many food fish have decreased markedly 

 in numbers due to overfishing, pollution of 

 streams and lakes by sewage and chemical 

 wastes, and other causes. For this reason the 

 federal and state governments have placed 

 certain restrictions on fishing and have also 

 undertaken to propagate certain species arti- 

 ficially. These include fresh-water species 

 such as whitefish, lake trout, pike perch, 

 and bass, and marine species such as codfish, 

 haddock, salmon, flounders, and sardines of 

 the Pacific Coast. 



Among the fish of benefit to man should 

 be mentioned the top minnows {Gambusia, 



Fig. 266) which feed voraciously on mos- 

 quito larvae. These are placed in bodies of 

 fresh water to prevent the breeding of mos- 

 quitoes that transmit malaria and yellow 

 fever. 



The scales of the garpike are used for 

 jewelry and novelties. 



In recent years, considerable use has been 

 made of fishes for experimental animals, 

 especially in the fields of genetics, embryol- 

 ogy, animal behavior, and pharmacology. 



There has been a tremendous growth of 

 interest in tropical fishes; many of them are 

 popular for the home aquarium. Pet shops 

 now stock manv kinds of fishes for both 

 scientists and hobbvists. 



A BRIEF CLASSIFICATION 

 OF LIVING OSTEICHTHYES * 



(For reference purposes only) 



About 40,000 living species of fishes are 

 known from the entire world according to 

 Schultz; of these, about 168 families and about 

 3300 species occur in North America. The 

 families shown in Fig. 252 are some of the 

 better known representatives of the orders 

 listed below: 



Class 1. Osteichthyes (bony fishes). 

 Subclass 1. Choanichthyes. 



Order 1. Neoceratodida. Ex. lungfishes 



(Fig. 252). 

 Order 2. Crossopterygiida. Ex. lobe- 

 finned fishes. 

 Suborder 1. Coelacanthiina. Ex. 

 Latimeria (Fig. 263). 

 Subclass 2. Actinopterygii. Ex. rayed fins. 

 Superorder 1. Chondrosteica (cartilage 

 and bone). 

 Order 1. Polypterida. Ex. lobefinned 



fishes (Fig. 252). 

 Order 2. Acipenserida. Ex. sturgeons 

 (Fig. 252). 

 Superorder 2. Holosteica (bone and car- 

 tilage). 



* TTiis classification is according to Leonard P. 

 Schultz, Curator of Fishes, United States National 

 Museum, Smithsonian Institution, 



