ings — a movement imitative of the swaying and trembling of the nearly always 

 breeze-blown leaves and flowers and twigs amid which they sit.) Even when 

 perching, these butterflies of the 'intermediate' class expose the upper side 

 as freely and fully as the lower, if not more so, and in many cases the upper 

 side is the more specially and minutely patterned of the two. The prevailing 

 color of all such butterflies, or at least the color which occurs almost unvaried 

 on the greatest number of species, is dusky olive brown, — * black' which is 

 not black. This is just the average tint of the smaller shadows amidst vege- 

 tation. On this groundwork of perfect shadow-color are painted all sorts 

 of leaf, sun-fleck, and flower-pictures — more delicate and elaborate on species 

 which more frequently alight, bolder and simpler on the more constantly 

 aerial kinds. (See Fig. 129.) The commonest tint of the light ' picture '- 

 markings, which stand framed in the pure, elusive shadow-color, is bright- 

 (often somewhat greenish) yellow,— and this, after white, is the color of the 

 majority of flowers. Furthermore, it is the color — barely clarified — of almost 

 all brightly sunlit foliage. No wonder, then, that the presence of this color 

 in clear and delicate generalized picture-patterns, with the due amount of 

 contrasting, dusky shadow-tint, strongly tends to 'obliterate' the broad, flat 

 wings of butterflies. So many and so various are these picture-patterns, in 

 kind and in degree (of elaboration and finish), that it would be hopeless for 

 us here to attempt a comprehensive account even of the main types of them. 

 Here as elsewhere in our book, the description of a few characteristic cases 

 must suffice. 



Papilio polydamas, of North America, and some of the dark Satyrince, will 

 serve to typify the butterflies which have a shadow-like ground-color overlaced 

 with bright, generalized pictures of living vegetation. Some of these, Paptt- 

 ionidce especially, have such patterns beautifully clear on the under as well 

 as the upper sides, and often rest with tightly folded wings. The patterns of 

 their under sides, in fact, though usually less bold and bright than those of the 

 upper, are also as a rule more fine and delicate, as if to admit of a closer in- 

 spection. And in truth it is chiefly at times when the butterfly has relaxed 



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