52 WILD BIRDS 



puzzle " Why have so many of them those dusky 

 shadings and rings or eyes and tiny spots on the 

 underside of their wings ? " is put before us again. 

 I think I have studied this matter so far as it is 

 related to several English butterflies as closely as 

 most observers. The large heath butterfly I have 

 watched most carefully in several years, and also 

 the common blue butterflies, the orange-tip, with 

 others. What I have never been able to find is 

 the foe against which they have been armed with 

 these marks and dusky shades. Professor Weis- 

 mann has written about the protective marks and 

 colours of butterflies ; and he writes with such entire 

 confidence that one is half-ashamed not to go all 

 the way with him. If he be right, this problem is 

 solved. Not a letter on our butterfly's wing is a 

 mystic letter. There is no chaos for us in these 

 colours and marks it is cosmos everywhere in the 

 insect world, and I suppose in the bird world too. 



Weismann does not overlook the question, 

 " Against what enemies are the butterflies protect- 

 ively coloured, shaded, and marked on the under- 

 sides of their wings ? " He allows and answers 

 the question in a sweeping sentence " The pre- 

 liminary postulates of the theory have been dis- 

 puted, for instance, that diurnal butterflies are 

 attacked and eaten by birds, but observations 

 specially directed towards this point in India, Africa, 

 America and Europe have placed it beyond all 

 doubt. If it were necessary I could myself furnish 

 an account of my own observations on this point.'- 



