THE ACTION OF LIGHT 



573 



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fep 



FIG. 181. CHROMATIC ADAPTATION. Small flat-fish (Rhomboidichthya podas), photographed 



on ground of natural composition, gravel and sand of various degrees of coarseness. It 



is to be noted that the fish is completely uncovered, although appearing to lie under 



gravel, etc. (Sumner, 1911.) 



(Reproduced by the kindness of Dr Sumner. ) 



