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I'HE BOOK OF FISHES 
Undersea Photograph by Dr. W. H. Longley 
UNDERSEA STUDY OF A FAMILY GROUP OF YELLOW GRUNTS 
To realize the full value of this amazing photograph, one must remember that these multi-hued fish 
are at home among the coral and sea-fans of their natural habitat, many feet beneath the surface of the 
Gulf Stream. The Yellow Grunt is one of the species of fishes which makes a croaking or grunting sound, 
a fact from which it derives its namei A distinguishing feature of this fish is its bright red or orange color 
at the base of the jaws and inside the mouth. The color patch is revealed to its fullest extent when the 
mouth is opened wide in the presence of an enemy, or when it invites the services of the Butterfly fish to 
enter between its jaws and extract certain parasites attached to the walls of its mouth. 
