PISCES, TRUE FISH 



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Family Spliyraenidae. — Barracudas. This group includes vicious, 

 voracious, pikelike fishes of the warmer seas. There are 15 species. 



Family Poljaiemidae. Threadfins. This common name comes from 

 the pectoral filaments. These are found among collections from the 

 Gulf of Mexico. 



Family Istiophoridae. — Sailfishes. Among this group are found 

 some of the swiftest of fishes. The dorsal fin projects high above the 

 body. 





Pig-. 247. — Large-mouthed black bass, Micropferus salmoides. The prize fresh- 

 water game fish. (From Metcalf, Textbook of Economic Zoology, published by Lea 

 and Febiger, after Smith.) 



Fig. 248. — Marine croaker, Micropogon undulatus. (From Metcalf, Textbook of 

 Economic Zoology, published by Lea and Febiger, after Smith.) 



Family Scombridae.— True Mackerels. These fish are a pretty, 

 metallic blue in color and are very important commercial fish of the 

 Atlantic. They live in great schools. 



Family Cybiidae. — Spanish Mackerel. These mackerels have a 

 scaly body. The tail is usually quite widely forked. They are fine 

 food fish and are very abundant in the Gulf of Mexico (Fig. 246). 



