50 



KNOWLEDGE. 



February, 1913. 



at the tip, and a brilliant yellow bar concealed. 



Figure 50, numbers 1 and 4, are "Green-veined 

 whites." It is well known that these vary very much, 

 so that they have been divided by some authors into 

 several species, and the curious thing is that, as the 

 colours and the markings of the hind wing vary, so 

 precisely do the colours and marking vary at the tip 

 of the fore wing. 



Figure 50, number 3, is the " Silver-washed 

 Fritillary," in which the green of the hind wings is 

 repeated at the tip with sometimes a little of the 

 silver. In other fritillaries, more or less of the same 

 arrangement will be found and in the "Pearl- 

 bordered Fritillary- " (see Figure 50, number 7), 

 the brick red patches which are on the hind wing, 

 are more or less repeated, with part of the paler 

 yellow at the tip of the fore wing and only 

 there. I do not know what this red brick may 

 represent, but it is evident that to have a patch of a 

 different colour at the tip of the fore wing would 

 render the creature much more conspicuous. 



Figure 50, number 6, is the " Painted Lady " in 

 which the brown and grey of the fore wings are 

 repeated at the tip of the fore wing, while the 

 brilliant pink and yellow are concealed. 



Figure 50, numbers 8 and 9, are two specimens of 

 the "Grayling" or " Rock-eyed Underwing." The 

 markings of the hind wing vary a good deal and 

 in exactly the same manner do the markings of the 

 fore wing vary to correspond, both at the tip and 

 along the front margin. 



Figure 50, number 10, is the common little butterfly 

 variously called "Small Heath" and "Least Meadow 

 Brown." In this, when closed, the brown and grey 

 are repeated at the tip, while the yellow and orange 

 and the eye spot of the fore wing are concealed. 



Figure 52 is the " Marbled White" in which the pale 

 and thin-lined pattern of the hind wing is repeated 

 at the tip of the fore wing, while the darker colouring 

 of the fore wing is concealed. This is more obvious 

 in the American form which has a brown lined 

 pattern on the hind wing exactly repeated at the tip 

 of the fore wing. I do not know what the markings 

 in the American species may represent, but it may 

 not be a wild conjecture that the object of the 

 pattern in the English butterfly is indicated by the 

 surroundings which I have given it, and that it 

 conceals the creature by imitating the dead panicles 

 of grass which abound in those dry places near 

 woods where the butterfly is so often to be found, 

 and on which it frequently settles. 



We do not see the full force of any argument till 

 we look at it (so to speak) from the opposite side ; 

 and this detail in protective colouration is clearly 

 brought out by the cases where it is not needed. 

 Contrast, for example, the underside of the wings of 

 the " Comma," " Large Tortoise-shell," " Peacock," 

 where the protective colouring is spread over the 

 whole of both hind wings, with the repetition of the 

 hind wing pattern in " Small Tortoise-shell," " Red 

 Admiral," and so on. 



It is curious that in Anosia menippe Hiibner — a 



butterfly which is now sometimes caught in England 

 and which is said to be protected by a nasty taste — the 

 paler colour of the hind wings is repeated in a patch 

 at the tip of the forewings, while the colour of the 

 rest of the fore wings resembles that on the upper 

 surface. The detail seems to indicate that the 

 bright brownish-yellow may not in these cases be 

 warning as had been supposed. On that supposition 

 it would seem difficult to find a reason (and a reason 

 must exist) for this curious bit of repetition. 



Figures 53 & 51 are two species of the leaf butter- 

 flies whose likeness to dead leaves is now so familiar 

 to us all. These, of course, do not fold the fore wing 

 behind the hind wing, and there is, therefore, no 

 reason for any repetition of the hind wing pattern. 

 The tip merely displays a little imitation of a fungus. 



The head of the insect is placed between the wings 

 and hidden, when it is at rest. This puts out of 

 sight the conspicuous eye, which would perhaps tell 

 a tale, so complete are the arrangements for conceal- 

 ment. 



An interesting point here occurs : most dead leaves 

 hang down ; do the Kallimas take that position or do 

 the leaves of the trees on which they rest retain the 

 upright position when dead ? I have not seen this 

 noticed by the authors on the subject. 



The Nyctalemon Moth of the Andaman islands 

 evidently represents a dead leaf, as it has an imitation 

 of a midrib throwing an imitation shadow on one 

 side, and has also a tail to represent the stalk. But 

 most moths appear to rely on the upper surface of 

 their wings for concealment. Many of them, as the 

 so-called " Underwings," have their brilliant colours 

 on the upper surface of the hind wings and conceal 

 these, when they are resting, with the fore wings, 

 which are protectively coloured. This no doubt 

 applies to some butterflies whose wings are coloured 

 in the same way. 



The " Skippers " form a group half-way between 

 the Moths and the Butterflies. Our " Dingy 

 Skipper" is said to rest with the wings folded over 

 its back in the exact position of a noctuid. Now the 

 " Dingy Skipper " shows no sign of any repetition 

 at the tip of the fore wing of any special colour on 

 the hind wing : but the " Large " and the " Small " 

 Skippers both show the usual repetition of the hind 

 wing colouring. How they rest I am not certain. 



Every one will, I am sure, agree that sufficient 

 proof has been given of the existence of this curious 

 and minute arrangement of Nature for the protection 

 of these little creatures ; but it is in all such cases to 

 be noticed that there is often some little imperfection 

 in the work of protection. It seems as if Nature in 

 Evolution was sometimes actuated by two or more 

 contradictory plans, which she has to harmonize as 

 best she can. There is the tendency to some pro- 

 tective resemblance, but there is also the tendency to 

 brilliance of colour or design for the purpose of 

 recognition by or attraction of the opposite sex ; and, 

 lastly, there seems to be a real tendency to develop 

 colour in special places, as, for example, along the 

 nervures of Lepidoptera, as in the " Green-veined 



