ORDER IV. MOTHS AND BUTTERFLIES. 137 



ascertained. Some naturalists think that these feelers serve 

 to protect the eyes, but the more rational opinion prevails 

 that the antennee, with which all insects are provided, are 

 probably the organs of hearing. They are hollow, provided 

 with muscles, and placed on each side of the head, like the 

 ears of beasts, reptiles, and fishes. 



The use of the proboscis is much better known : it is a 

 spiral tongue, formed to coil up like the spring of a watch, 

 and it is by means of this organ that the insect is enabled 

 to pump out the juice of flowers. This spiral tongue, which 

 answers the purpose of a mouth, is placed between the eyes, 

 and consists of two lateral halves which are closely united, 

 and which form a hollow tube like the proboscis of an ele- 

 phant. Its length varies considerably in the different spe- 

 cies of butterfly. We find the longest ones in the Hawk- 

 moths ; but a few species have none at all, as the silk- worms, 

 for many live as perfect insects only a few days, and can 

 get along without the trouble of procuring food. 



I have often amused myself with experiments upon the 

 Hawk-moths and Butterflies which were hatched in a warm 

 room as early as the month of March. I have fed them 

 with sugar, holding the insect in my fingers by the wings, 

 and have seen them seize the piece of sugar with their fore 

 feet and, thus holding it, unfold their proboscis, and with its 

 saliva moistening the sugar, then sucking the juice, which 

 could easily be perceived ascending the trunk. This is an 

 experiment which every one can make at pleasure. 



From the most ancient times it has been observed that 

 some lepidoptera make their excursions only during the 

 night, and conceal themselves during the day ; while others 

 are seen flying about only in the daytime, and conceal 

 themselves at night. The former are called Nocturnal 

 Lepidoptera, as Moths, Millers, Hawk-moths, etc., which 

 are recognized by their having antennae without a knob at 

 the end, e. g., the Saturnia lo (Figs. 27 and 28). 



