are decidedly of the tree-bark (or rock-surface) type. These patterns are 

 at once finer and less fine than those of the flatly-applied lepidoptera. Less 

 fine, as they less minutely and exactly depict one especial type of surface in 

 one especial view; more fine, in that they combine the elements of several 

 varieties of background at somewhat varying distances, — the bark of the tree 

 on which they sit, with its markings lessened by distance and foreshortened 

 in extreme side view, front or side views of bark-surfaces on other, farther 

 trunks or branches; or even still more extended vistas of the mixed forest 

 background. Examples of this type, in full and simple development, are the 

 several familiar northern butterflies of the genera Grapta and Vanessa, as 

 well as many nearly or remotely allied tropical forms. Tree trunks, tree 

 branches, and rocks are the characteristic resting-perches of these butter- 

 flies, though they are by no means confined to them — any more than their 

 patterns, beautiful and efficient for 'obliteration' though they are, show 

 that ultimate touch of specialization which would best qualify their wearers 

 for strictly specialized perching-habits. They are swift, sharp fliers, these 

 Graptas and others, and their upper sides have as a rule wholly different col- 

 ors and patterns from their lower, with different obliterative functions. But ' 

 that is another story, to be told later in the chapter. 



Some of the much larger tree-trunk butterflies which habitually sit with 

 folded wings, such as the famous Calligo eurylochus, and others of that genus, 

 miscalled "Owl Butterflies," have a subtile obliterative pattern in which the 

 picturing of near tree-bark is almost wholly replaced by that of more ex- 

 tended and diversified vistas of the brown forest interior— a pattern, in short, 

 more like that worn by certain forest birds, such as the Ruffed Grouse. (See 

 Plate II, and Chapter VI, pp. 38-41.) This accords with the fact that, owing 

 to their great size, these butterflies can almost never have as a complete back- 

 ground for their 'profile' the bark of the tree on which they are perching, 

 as the small Graptas, etc., often can. (This is all the more likely on trees 

 with rough and flaky bark — a condition more characteristic of northern trees 

 than of those of the Calligo's native forests.) The species of Calligo which 



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