least a most significant accompaniment, of this peculiar habit, was not far to 

 seek. The 'secant' stripe, crossing the insect transversely from fore-wing 

 tip to fore-wing tip (a type of marking very common among moths, whose 

 patterns, like those of butterflies, are built on the simple basic laws of 'oblit- 

 eration'), was on this kind specialized into a wonderfully sharp and vivid 

 picture of a vertical bark-ridge. Such picturing of outstanding substance and 

 cast shadow plays a large part in the disguisement of many animals of many 

 classes, — nor is it, among moths, confined to those that perch on tree trunks. 

 It reaches equally high and various development among the ground-perching 

 kinds. These — the sylvan ones at least — tend to be brown (as the perchers 

 on tree trunks tend to be gray). Their general scheme of color and pattern 

 is much like that of the sylvan terrestrial butterflies, but they sit, for the most 

 part, flatly applied, instead of perpendicularly folded, and therefore need 

 still more direct and simple ground-picturing patterns. Sometimes, indeed, 

 they present a resemblance hardly other than mimetic to single, brown, dead 

 leaves. No doubt there are even full-blown brown-leaf mimics among 

 them, as there are probably green-leaf mimics among those that perch on 

 live foliage. But in the main, their coloration is obliterative, not mimetic — 

 if anything, more patently so than the corresponding coloration of the bark- 

 perchers. The leaf-strewn forest floor is more uneven, more studded with 

 projections and pitted with depressions, than are tree trunks, and though a 

 moth sits flatly outspread on it, his background tends to be less evenly and 

 plainly near than is the bark moth's. And, though the ground moths' "cryp- 

 tic" patterns contain less of the element of diverse-distance picturing than do 

 those of the perpendicularly-folding butterflies which haunt like situations, 

 the essential differences between the disguises of these two lepidopterous 

 types are comparatively smaU, and sometimes quite in abeyance. Again, 

 there is even close likeness between the patterns of some of these moths and 

 that of certain terrestrial snakes, such as the Copperhead (Plate XI). Both 

 picture dead, prostrate leaves, with their light, sharp edges and blurred shad- 

 ows. For pure and subtile realism, the background-pictures worn by some 



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