MASTERS OF THE WATER-BONY FISHES 261 



Scaly-Fin Fishes: Suborder Squamipinnes {"scaly fin") 



Very few fishes can match the beauty of color, form, and movement of these 

 mostly tropical fishes. They glide effortlessly through the water, their lustrous, 

 velvety bodies never failing to impress the diver. There are three quite distinct 

 families. All possess dense scalation on the vertical fins, which adds to the soft 

 and veh'ety appearance. All are strongly compressed and deep of body, and most 

 use the pectoral fins in a flapping manner to aid in their movements. This method 

 of propulsion is not so exclusively used as it is in the parrot fishes. The mouths 

 of the scaly-fins are small and the teeth small and brushlike (except in tangs), 

 so most are invertebrate- and algae-eaters exclusively. Various shades of yellow, 

 blue, and black are predominant colors. Their distribution is world-wide, chiefly 

 over and around reefs. 



SPADEFISHES: Family Ephippidae 



These fishes are a bit off^ the beaten track for scaly-fin fishes. The color is 

 predominantlv silvery, and there is a prominent spiny dorsal fin. Spadefishes 

 school rather densely inshore and about reefs, wrecks, rocks, and pilings. They 

 swim faster than do other scaly-fins and more in a typical "fishy" manner than 

 most scaly-fins do, using the tail for propulsion. There are few species, mostly in 

 tropical seas. 



SPADEFiSH (paguala) : Chactodifterus faber— Color Plate 7 



Size: Averages 1 foot. Up to 3 feet. 



Weight: Up to 20 pounds. 



Distribution: Cape Cod to Brazil. Most common in the West Indies. 



Identification: The silvery to whitish color with black crossbands is distinctive. 

 As the fishes get larger, the bands disappear. The silhouette is the best field mark. 



Habits: The food consists primarily of invertebrates, mainly crustaceans. Cteno- 

 phores also are eaten. 



Similar Species: Chaetodifterus zonatiis is the similar spadefish of the western 

 coast of Mexico. It ranges rarely as far north as San Diego. 



BUTTERFLY FISHES AND ANGEL FISHES: Family Chaetodontidae 



Size is the characteristic which separates the butterfly and angel fishes. The 

 former are small and very active, almost birdlike in their movements, and are 

 mostly seen traveling in pairs. The latter are larger, have stately movements, and 

 travel singly, in pairs, or in small groups. The young of both are usually very 

 diff'erent from the adults in pattern and in coloration. These are among the most 

 typical of reef fishes, found throughout the world. 



BUTTERFLY FISHES: Chaetodon species 



The habits of these species are so similar that they had best be considered as 

 a group. All are very active fishes and have the flitting movements of a butterfly, 

 hence their name. They are exceedingly brightly colored, principally with yellow 

 and black. Owing to their small size and their lack of great speed, it would be 

 expected that they would be secretive, but they are not. They depend on extreme 

 alertness and activity, as do the demoiselles, for safety. Many of them also add 



