88 NATURE SKETCHES IN TEMPERATE AMERICA 



an indifference as to the kind of leaf they chose to rest upon. 

 Others found later were either on the ground or were near it, 

 ranging within a distance of from two to ten inches above 

 it. Those resting on the leaves showed, moreover, an in- 

 stinctive indisposition to fiy when I carefully handled or 

 picked the leaves. 



Three days previously, during a strong wind, my attention 

 was drawn to one of these moths conspicuously exposed on the 

 upper surface of a leaf, which remained there for a number of 

 hours despite the waving of the plant by the wind. The marked 

 indisposition of these moths to fly when I came near them indi- 

 cates in an excellent manner an inherent behavior which seems 

 to develop coincidently with adaptive changes of form and 

 color to their surroundings. 



Another sjjccies of these rolled-leaf moths which I found 

 possessing similar habits and associated in the same environ- 

 ment with the foregoing species, is the Datana 07igussi. It 

 is shown in the second plate illustration, also photographed 

 from life. This is a strikingly beautiful insect and is richly 

 marked. But little conception of its .specially protected life 

 among forest herbage can be gleaned by viewing the usual 

 museum specimens with their wings dried in an open position. 

 In the daytime when these moths are resting and require 

 greatest protection, the wings are clo.se to the sides, and it 

 is in this position only that they ])re.sent the leaf-like form. 

 The front of the thorax is colored a rich velvet chestnut-brown, 

 the upper wings being transversely streaked with brown on a 

 yellowish color ground, and the edges of the wings have a 

 brownish, lightly .scalloped border. These colors and markings 

 are highly variable, and thereby aid in matching the vari- 

 ously colored dried leaves. Likewise, the oblique stripes bear 

 a marked illusion to the veins. 



This moth, on the whole, presents a general, rather than a 

 special resemblance to leaves. The dried leaves composing 

 the background were mostly beech and averaged in length 

 longer than the moth's body. They were thrown about on 

 the groimd by the wind, causing a cri.s.s-crossing and over- 

 lapping in arrangement. Again, some of them that were 

 curled up quite strongly lengthwise, were of variable hues. 



