CONCEALMENT OF A LARGE INSECT 201 



as would be expected among the leaves and varying lights 

 on a bush, ^ but the following is a more remarkable example. 

 On Kimmi Islet I was looking at a bush thinly covered 

 with small leaves, and thought I saw a small brown 

 " micro " moth sitting on one of the leaves. But gradually 

 it became obvious that what I was looking at was not a 

 small moth, but part of the ventral aspect of an enormous 

 green Saturnid caterpillar, which was on the lower surface 

 of a twig, its anterior segments being at an angle with 

 the twig, as in the common attitude of many large cater- 

 pillars, such as those of our English hawk-moths. The 

 closely folded brown legs on the first three segments had 

 made the brown area which, against the green of the rest 

 of the caterpillar, had been mistaken for a small moth 

 sitting on a leaf. There was a whitish-green stripe running 

 along the mid-ventral line of the caterpillar, which must 

 have served to break up the otherwise uniform green 

 area, and helped to render the huge form difficult to be 

 seen. The curious point was that when the insect had 

 once been visualized, I could not un-see it again, and found 

 great difficulty in realizing how I had at first failed to 

 discern it. Some of the natives were called up and asked 

 if they saw anything on the bush, and their surprise was 

 as great as mine when I pointed out the caterpillar. The 

 moth was reared, and proved to be Bunaea phaedusa. 



When procryptic colouring is dealt with, place must 

 be found for mention of Seasonal Variation. Certain 

 butterflies have been known for some years to have 

 appearances differing greatly in the wet and dry seasons. 

 So marked are the differences in the Nymphaline genus 

 Precis, for example, that two forms of P. sesamus, one 

 salmon-pink above, the other deep blue, with extreme 

 difference of pattern and colour on the under surfaces, 

 were thought to be distinct species until G. A. K. Marshall 

 bred one from eggs laid by the other. ^ 



^ The Colours of Animals, p. 42. 



' Trans. Ent. Sac, 1902, part iii, p. 414 et seq. 



