nificance in this superficial likeness between animals so remote from one 

 another, fundamentally, as seals and fishes, which yet live much of the time 

 under common conditions, and have somewhat similar outward forms. Their 

 superficial resemblance is all the more notable in that the like colors and 

 patterns are produced in totally different ways in the two cases, those of the 

 fishes being in the skin, and those of the seals made with minute external 

 hairs. On the other hand, this is no more remarkable than the many familiar 

 cases of superficial resemblance among widely different land animals which 

 have acquired kindred habits of life — e. g., some hummingbirds and hawk- 

 moths. 



To sum up the main facts about the disguising-coloration of fishes, 

 as far as they are known to us : All ' daylight ' kinds are obliteratively shaded, 

 with the possible exception of a few mimetic forms; while their particular 

 adaptive developments of color and pattern correspond to those of birds 

 and lizards and butterflies on land, and are almost — perhaps quite — as highly 

 and beautifully diversified. But about the exact nature of these special adap- 

 tive costume-developments of fishes, little is yet known. The subject's very 

 inaccessibility lends it an exceptional fascination, and it must ultimately receive 

 the profound and detailed study it deserves. 



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