A DETAIL IN THE PROTECTIVE COLOURATION 



OF BUTTERFLIES. 



(Read before the Ashmolcan Society of Oxford.) 

 By The Rev. F. BENNETT, M.A., Oxon. 



I DO not know whether the particular detail of plete. In almost all cases the hind wing is rounded, 

 protective colouration to which I wish to draw while the fore wing is more or less triangular 

 attention has been already described in any of the in shape and ends in a point, and thus the tip 



Figure 47. 

 Orange Tip Butterflies on WildXhervil. 



Figure 48. 

 Bath White Butterflies. 



multitudinous works dealing with that fascinating 

 subject ; but, if it has, I will refrain from exclaiming 

 with the ancient author: "May they perish who 

 have made our observations before us ! " 



In the case of many of our English butterflies, 

 when one of them alights, and intends, not merely to 

 sun himself or display his beauties to an admiring 

 sweetheart, but to rest for some time, he first folds 

 his wings together closely back to back, and then 

 draws his fore wings downwards in such a manner 

 that they are, as completely as possible, covered by 

 the hind wings ; and it is obvious to any observer 

 that in very many cases the underside of the hind 

 wings is the part so coloured in various ways as to 

 resemble the surroundings and thus conceal the 

 creature from its enemies. 



I say " as completely as possible " ; for the 

 difference in the shapes of the fore wings and hind 

 wings prevents this covering from being quite com- 



of the fore wing remains uncovered and visible. 



Now the beautiful detail which I propose to 

 illustrate is this: — that the uncovered portion of 

 the underside of the fore wing repeats in a great 

 number of instances the pattern and colouring of 

 the under surface of the hind wing and thus carries 

 out to perfection the concealment ; while the 

 remainder of the under-surface of the fore wing 

 covered when at rest by the hind wing, has often 

 quite different colouring and is in many cases of 

 most brilliant and conspicuous hues. 



As I first observed this detail in the " Orange 

 Tip " (I prefer the ordinary English names to the 

 scientific ones, as each butterfly has such a number 

 of systematic synonyms), I will give that charming 

 little herald of spring the first place in the illustra- 

 tions (see Figure 47), though it is not perhaps the 

 best of them. 



No one will, after looking at the picture, doubt for 



47 



