212 



THE NATURE BOOK 



who would learn to know the insects are 

 just as likel}- to be " tricked " by the 

 extraordinar\- guises they assume as 

 a means of protection as are their natural 

 foes. It follows, therefore, that this 

 subject comes well within the scope of 

 these papers. 



The three common White Butterflies. 

 with which everybody is more or less 

 familiar, are 

 known r e s p e c - 

 tixely as the Large 

 White {Pier is 

 Brassiccv), the 

 Small White (P. 

 Rap a) and the 

 G r e e n - V e i n e d 

 White (P. Napi). 

 The first is readily 

 distinguished b y 

 its size ; the two 

 latter are fre- 

 quently confused, 

 as they are both 

 extremely abund- 

 ant, and very 

 similar in colour. 

 The Green-veined 

 White, however, 

 may be distin- 

 guished by observ- 

 ing the under side 

 of its hind-wings, 

 which are conspic- 

 uously veined with 

 green, from which 

 feature the insect derives its popular 

 name. It is well known that during sun- 

 light these insects are always on the 

 alert, and also that they are very capable 

 insects when on the wing. It is obvious, 

 therefore, that during sunlight they need 

 little or no protection except their power 

 of flight ; but at night and on dull days, 

 when they rest, these White Butter- 

 flies are conspicuous objects and necessarily 

 have to hide away beneath leaves and in 

 .similar situations. 



Now, during the summer of 1907, 

 Green-veined White Butterflies were very 

 abundant in my flower garden (this year 

 I have seen but few), and I then dis- 

 covered one method by which these 

 insects secured protection during the 

 nights and the whole of dull and wet 

 days. Indeed, during the month of May, 



I could almost invariably find in the garden 

 at such times a fair number of these 

 butterflies. It so happened that some 

 clumps of the familiar Ribbon or Lady's 

 Grass had been allowed to grow large, 

 and while pulling out some of this I 

 found that I frequently disturbed a 

 Green-veined White Butterfly. For a 

 moment this surprised me, and then I 

 suddenly realised 

 the meaning of it. 

 I im mediately 

 went to another 

 clump of the 

 grass at another 

 part of the garden 

 and disturbed it, 

 and at once but- 

 terflies appeared. 

 Another clump 

 yielded a similar 

 result ; indeed, 

 each of the whole 

 six clumps pro- 

 Added from one to 

 four butterflies. 



W^hy were the 

 butterflies amidst 

 the grass ? To 

 answer that ques 

 tion I will ask my 

 reader to glance at 

 the flrst illustra- 

 tion. There are 

 shown some blade '•, 

 familiar 

 Observe, 



HAWK-MOTH RESTING ON THE BARK 

 OF A POPLAR TREE. 



of the 

 green and white striped grass, 

 too, that amongst them there are two 

 Green-veined White Butterflies. In the 

 photograph on p. 211 the butterflies are con- 

 spicuous enough, because I have removed 

 some of the blades from before the insects 

 so as to show them in the picture. But 

 let me now ask my reader to think of the 

 conditions as they were in reality. The 

 blades of grass striped and shaded irregu- 

 larly with green and white, the butter- 

 flies hidden in amongst the crowded 

 blades with their white wings pressed 

 closely together, exposing only the imder 

 sides of the lower wings — the green- 

 veined wings. The harmony was per- 

 fect ; you might look from above a hundred 

 times and yet never see a butterfly ; to 

 accomplish this yoti had to assist your 

 eyes witli ycrar hands. 



