I/O THE INSECT WORLD. 



transversely, one sees, according to Rdaumur,* that the interior is 

 composed of three small rings. Consequently, there are three canals 

 in the trunk : one central, the other two lateral (Fig. 138). Are all 

 these three used to conduct the juice of flowers into the butterfly's 

 body ? Reaumur has made some very interesting observations on 

 this subject, by observing a moth which was sucking a lump of 

 sugar whilst its portrait was being taken. 



" I held in one hand," says Reaumur, " a powerful magnifying 

 glass, which I brought near to that part of 

 the trunk I wished to examine ; I was some- 

 times half a minute, or nearly a minute, 

 without perceiving anything, after which I 

 saw clearly a little column of liquid mounting 

 quickly along the whole length of the trunk. 

 Often this column appeared to be intersected 

 by little balls, which seemed to be globules of 

 air which had been drawn up with the liquid. 

 "This liquid ascended thus during three or 

 four seconds, and then ceased. At the end 

 of an interval of a greater number of seconds, 

 or sometimes after an interval as short, I saw 



Section of f iL'tfrfly-s Trunk some fresh lic l uid mounting up along the trunk, 

 after Reaumur. ' But it was straight up the middle of the trunk 

 that it seemed to ascend. 



" The Author of Nature has given to insects means of working, 

 which, though very simple, we cannot divine, and which often we 

 are not able even to perceive. Whilst I was observing the trunk of 

 our butterfly, between the columns of liquid which I saw ascending, 

 there were, but more rarely, times when I saw, on the contrary, 

 liquid descending from the base of the trunk to the point. The 

 descending liquid occupied half or two-thirds of the tube. It was 

 no longer difficult to perceive how the butterfly is able to nourish 

 itself on honey, the thickest syrup, and even the most solid sugar. 

 The fluid it sends down is probably very liquid ; it drives against the 

 sugar, moistens, and dissolves it. The butterfly pumps this liquid up 

 again when it is charged with sugar, and conducts it along as far as 

 the base of its trunk, and beyond it." 



The life of the perfect insect is generally very short. Like nearly 

 all other insects, they die a soon as they have propagated their 

 species. The female lays her eggs, which vary in shape, on the plant 



* Planche 9, Fig. IO, 5e Memoire, " Sur les parties exterieures des papillons." 



