191 



HARDWICKE'S SCIENCE-GOSSIP. 



[Sept. 1, 1867. 



These general facts as to the distribution of 

 colour are the first stage in that process of " dis- 

 guise" which becomes so wonderfully developed in 

 a few conspicuous cases. The next stage is exhi- 

 bited by the fact that there is a general agreement 

 between the colour of a large number of moths and 

 the ^prevailing tints of nature at the season when 

 they appear. Out. of fifty-two autumn-flying moths, 

 it has been noticed that a large proportion are of 

 various tints of yellow and brown, so as exactly to 

 match with the " sere and yellow leaf ; " while in 

 winter they are of grey and silvery tints, like the 

 washed-out leaves and grass, the fog and the hoar- 

 frost, which give a tone to every landscape at this 

 season. 



We now come to a closer and more special dis- 

 guise. Many of the moths that rest during the day 

 on paUngs or on the trunks of trees are marked and 

 coloured so as to match the tints of the bark and 

 lichens, and thus to escape observation. As exam- 

 ples of this numerous class, we may mention two of 

 our commonest species — the " Dagger " (Acronycta 

 psi) and the pretty green Agriopis aprilina. The 

 Lappet moth (Gastropacha quercifolia) when at 

 rest resembles very closely a small bunch of dead 

 leaves ; and at a little distance could hardly be 

 taken to be a moth, so curiously does it spread out 

 its hind wings so as to project beyond the others. 

 The accompanying cut (fig. 193) by [Mr. T. W. 

 Wood, is an accurate representation'of this insect 

 in°its attitude of repose. 



cjor. 



Fig. 193. Lappet Moth. 



One of the most curious of these resemblances is 

 that of the Buff- tip moth (Pygtera bucephala). This 

 insect closes its wings so as almost to form a 

 cylinder ; and on the tip of each wing is an oval 

 yellowish spot, edged with a dark brown double 

 line. The wings are greyish and hoary ; and the 

 head, again, is much contracted beneath the large 

 thorax, which is also of a buff colour, with a double 

 brown marginal line. The result of this arrange- 

 ment is that the insect looks at first sight like a 



piece of stick, one end being broken off "nearly 

 square, the other end more obliquely (fig. 191) ; and 

 as it often rests on the ground, among grass or on 

 leaves, it may easily be mistaken for a piece of a 

 broken branch which has fallen to the ground. Many 



Fig-. 194. Buff-tip Moth. 



more of these beautiful adaptations remain to be 

 discovered in our native insects. That most elegant 

 insect the Elephant Hawk moth is of a reddish-pink 

 colour, mingled with dull yellowish-green, and with 

 specks and streaks of white ; but it has not been 

 noticed how closely all these colours must assimilate 

 it to the handsome red-flowered Willow-herb (Epi- 

 lobium), on which the larva feeds, and on which the 

 female insect, while depositing her eggs, no doubt 

 often reposes. The petals of the common Epilobium 

 angustifolium, for instance, are of the same pinky- 

 red as the moth ; its stems and seedpods are green, 

 tinted with brown-purple or yellowish, while the 

 white filaments of its stamens correspond to the 

 white lines and streaks on the insect. It is evident, 

 therefore, that while reposing amid a clump of these 

 plants, the Elephant Hawk-moth, although so bril- 

 liantly coloured, must be exceedingly difficult to 

 detect, since every part of its body is of exactly the 

 same hue as some portion of the flowers. 



We owe the discovery of one of the most beau- 

 tiful examples of " disguise " in a native insect to 

 the talented young artist and close observer of 

 nature who has furnished the illustrations for this 

 article. He tells us that one fine afternoon in May, 

 being overtaken by a shower, he sought shelter 

 under a hedge, where, among other flowers, the wild 

 parsley (Anthriscus sylvestris) grew in the greatest 

 profusion. While observing the light and elegant 

 forms of these plants, he noticed what appeared to 

 be a small bunch of flowers projecting beyond the 

 rest ; and a closer examination led him to the inter- 



