148 A NATURALIST IN BORNEO 



of other insects. An enthusiastic anti-Darwinian to 

 whom I related this fact rejoiced at having found an 

 argument to combat the belief that the imitation 

 of sticks and leaves was of protective value to the 

 insects, but inasmuch as every believer in natural 

 selection supposes that these resemblances have been 

 evolved through the elimination of insufficiently perfect 

 and of unfit individuals by their enemies, and sup- 

 poses further that evolution is progressing to-day with 

 unabated vigour, the joy of the unbeliever appears 

 misplaced. 



A good many of the Phasmidce are nocturnal feeders, 

 and I have noticed a peculiar habit in some that I 

 have kept in captivity : during the daytime the insects 

 were quiescent, resting for hours together with their 

 long fore-legs stretched out in front of them and their 

 other legs sticking out at various angles to the body, 

 but at night they were somewhat more active, moving 

 about over their food-plant and munching the leaves 

 greedily. That the presence of light had practically 

 no effect on these two modes of living was shown by 

 the fact that the insects were quite as active after dusk 

 had fallen whether the room in which they were placed 

 was brilliantly illuminated or not, and conversely, some 

 specimens kept in a bathroom that was only imper- 

 fectly illuminated by a grating in one wall were as 

 quiescent in the middle of the day as specimens 

 exposed to bright sunlight. The same fact has been 

 observed of plants that at night adopt a sleeping atti- 

 tude, the leaves being turned at a different angle from 

 that which they adopt in the daytime ; if such a plant 

 be placed in a dark room and examined suddenly by 

 day it will be found that the leaves are in the waking 



