Protective Coloration in its relation to Mimicrij, etc. oGO 



Any one who has tried to catch a snake in the grass will 

 see at a glance why Nature tries to direct an enemy's 

 attention behind the animal he is hunting. The snake 

 for ever proves to be further on. It is hard to set one's 

 foot far enough ahead as he moves, just as a wing-shot 

 tends to shoot behind. Now Nature, realizing this, offers 

 the enemy the utmost inducement to strike too far back. 

 The strong cross-bars of the Reeves or the Copper Pheasant, 

 while visually they cut the tail to pieces when it is still, 

 are, as with the Peacock, by far the most visible part of the 

 bird as soon as he moves. The reason of this is that in 

 forward motion the longitudinal markings scarcely show, 

 while the transverse ones become conspicuous. To prove 

 this, any reader has only to blacken a few points an inch 

 or so apart on a white cord, and then move the cord longi- 

 tudinally, drawn tight across some aperture a few yards 

 away, the cord being only visible where it crosses the 

 aperture. He will see that its motion is distinguishable 

 much farther off" when the spots are in sight than Avhen 

 the unmarJced cord is passing. The spots correspond to 

 the tail-marks of the Pheasant, and the cord where it is 

 not spotted represents the bird's longitudinal markings, i. c. 

 his body-markings. 



Before closing I beg to say that I do not mean that I 

 am convinced that Mimicry and Common Warning Colours 

 have no hand in these resemblances. I merely point out 

 that the coloration of every individual of the " mimicking 

 groups " of butterflies seems to be the best conceivable for 

 effacing the aspect of its wearer, and also that it is per- 

 fectly conceivable that an external influence, like super- 

 abundance of certain very sweet flowers, could do the 

 whole thing. 



