THE SURVIVAL OF THE FITTEST 389 



running from near the top of the upper wings to 

 the base of the lower ones. At the extreme lower 

 point of the latter there is a curved, projecting 

 tail and another much longer one above it. Al- 

 though I often watched closely I could never find 

 it after it alighted in the dense forest. I could see 

 its gorgeous wings as it flew with great rapidity 

 through the hammock; then, as suddenly as the 

 turning out of an electric light, it was gone. One 

 day when I was in the hammock a Timetes flew 

 close by me and vanished within a yard of my face. 

 It seemed to disappear among some dead leaves 

 ■on a shrub before me and as I peered very closely 

 among them I discovered it, apparently as perfect 

 a dead leaf as any on the bush. The wings were 

 closed and much of the red color had faded, their 

 under surfaces had grown darker and were slightly 

 variegated with a smoky brown exactly the color 

 of the dead leaves. The lower tail was pressed 

 closely against the twig on which it had alighted 

 and formed a perfect petiole. This appeared to be 

 continued up two thirds of the length of the sup- 

 posed leaf as a midrib. This midrib seemed to be 

 actually raised but I afterwards discovered that it 

 is cleverly composed of color markings, so arranged 



