1904.] PACKARD— ORIGIN OF MARKINGS OF ORGANISMS. 443 



In his second paper^ Mr. Thayer points out that the coloration of 

 every individual of the " mimicking groups" of butterflies seems 

 to be the best conceivable for effacing the aspect of its wearer. 

 ^' Most animals," he well says, ''wear on their coats pictures of 

 their habitat.'' *' As I before pointed out, even the under side of 

 the wings and tails of hawks bear the general twig patterns so 

 common on forest birds, as if Nature found it worth while to efface 

 the white silhouette their wings' under sides would make when they 

 extended them while perching. We see how completely such 

 patterns (when couched, of course, as they always are, in the effa- 

 cive gradation) do help to obliterate a partridge, grouse, woodcock, 

 hare, or any other of almost all the species in every order ; since 

 they prove to be actual animated pictures of their environment. As 

 I said before, in my paper on so-called 'Banner-marks,'" these 

 forest-like patterns are found on forest creatures, and not on desert 

 creatures or ocean creatures. Sand birds are usually marked in 

 longitudinal, delicate patterns, very like those the sand assumes 

 when seen at the same angle at which one observes the birds them- 

 selves. Tigers and zebras are resolved into pictures of tall, strong 

 flags, grasses and bamboos, while the lion is a picture of the desert. 

 (It will some day be plainly understood that the effacive gradation 

 is the essence of the success of these patterns. Were they not 

 arranged to compose one perfect counter gradation, from top-dark 

 to under-white, they would appear merely as what artists call Mines 

 of quantity,' like the hoops of a barrel, emphasizing i\\Q rotundity, 

 not effacing it.)" 



Butterflies, he claims, are " mainly either flying pictures of various 

 combinations of flowers and their backgrounds, pictures of the 

 shadow under foliage, with delicate patterns of vegetation or flowers 

 drawn across it, as, for instance, in the North American Papilio 

 polydamas and the dark Satyrinae, or that they are wonderful repre- 

 sentations of flowers themselves, as in the Pierina^." He also 

 claims that ^'' any pattern is less conspicuous than bright, unshiny 

 monochrome." 



He likewise briefly recognizes the effect of rapid movement in 



1 " Protective coloration in its relation to mimicry, common warning colors and 

 sexual selection," Trans. Ent. Soc, London, Dec, 1903, pp. 553-569. The 

 copy kindly sent me by Mr. Thayer has some valuable emendations and addi- 

 tions. 



2 The Auk, xvii, 1900, p. 108. 



