MASTERS OF THE WATER-BONY FISHES 



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This has restricted the fishes' movements greatly. These fishes, not having flexible 

 operculums, utilize movements of the pectoral fins to help circulate water through 

 the gills. Propulsion is accomplished by rapid sculling motions of the dorsal 

 and anal fins, the tail fin being used only in moments of dire stress. As the 

 swimmer approaches one of these fish, it will at first face forward, then turn 

 around and flee with all its might. In flight, its dorsal and anal fins work very 

 hard and comically, moving the fish at a speed well under that of a swimmer 

 with flippers. The fish will rock from side to side every so often to look back 

 over its shoulder at its pursuer. It somewhat resembles parrot fishes in this 

 respect. After a while, discovering that escape is not possible, it will come to 

 rest near some protecting ledge or hole. 



Trunkfishes have very small mouths. They eat small invertebrates and plant 

 substances. Their distribution is world-wide in tropical seas. 



cowfish: Lacto-phrys tricornis— Color Plate 9 



Size: Averages 8 inches. Up to a little over 1 foot. 



Distribution: West Indies to Cape Hatteras. Straggles to Massachusetts. 



Identification: There is a spine over each e3'e and two spines near the rear 

 end of the shell. The coloration is a blotched green with beautiful iridescent 

 yellow and blue spots. 



Habits: This is a bottom fish found around reefs, rocks, and harbors. When 

 badlv frightened, it assumes an iridescent, light blue color. 



Similar Species: The shellfish hactofhrys bicaudaiis is a tropical reef species 

 reaching a length of 16 inches. It ranges throughout the West Indies and north 

 to Florida. There are spines on the lower rear angles of the shell, which is light 

 brown or greenish and covered with round, dark spots. 



Fig. ISO. The trunkfish, Lactophrys trigonias, moves slowly hy flapping 

 and anal fins. It steers with the tail fin spread fan-shaped behind. For pr 

 depends on its hard shell of fused, bony scales and adaptive coloration. 



; its dorsal 

 otection it 



