362 Hawaiian Fishes 



THE TRUNK FISH FAMILY 



Including the Cucolds or Cowfishes 

 130 Family Ostraciidae 



The trunk fishes are a very unusual family of tropical fishes. The 

 bodies of these fishes are enveloped in a bony box composed of a number 

 of six sided plates. These plates are bound together to form a rigid shell 

 in which only the mouth, fins, and tail are movable. The first dorsal fin 

 and the ventral fins are not present and the remaining fins are short and 

 small. 



Trunk fishes swim in a peculiar fashion. The dorsal and anal fins 

 furnish the propelling force by a sort of rotary sculling motion. The 

 caudal fin is used as a rudder except in times of emergencies when it 

 functions as in other fishes. 



Goode writes that "the chief function of the broad pectorals seems 

 to be that of forming a current of water through the gills, thus aiding 

 respiration which would otherwise be difficult on account of the narrowness 

 and inflexibility of the branchial apertures. When taken from the water, 

 one of these fishes will live for two or three hours all the time solemnly 

 fanning its gill and when restored to its native element seems none the 

 worse for its experience, except that, on account of the air absorbed, it 

 cannot at once sink to the bottom." 



These fishes have few enemies because of the shell and horns which 

 protect them. Living in shallow water, being bright in color, and slow 

 in motion, they are easily captured and are common in collection. They 

 are not poisonous when eaten and are often prepared by baking in the 

 shell. They live near the bottom in shallow water in all tropical sea. 



Of about twenty known species at least seven are known from 

 Hawaiian waters. 



Trunk Fish 



130-1 Ostracion cubicns Linne 



This fish is of a uniform dull color and is marked by small, black 

 spots over its head and belly. The back is convex in shape, while the 

 lower surface is broadly concave. The carapace is spineless and is marked 

 with four blunt ridges. The body reaches a length of about fifteen inches. 



This fish is distributed from the Red Sea, Zanzibar, Mozambique, 

 Mauretius, the Seychelles, and Ceylon, through the East Indies, along the 

 coast of Queensland, Japan, Melanesia, Micronesia, and Polynesia as far 

 as the Hawaiian Islands. 



