120 THE UNIVERSE. 



quence of this tactile communication, which Huber calls 

 antennal language. 



The following experiment, undertaken l^y this philo- 

 sopher, gives incontestable evidence in favour of the fact. 

 Having thrown a colony of ants into a closed and darkened 

 chamber, he remarked that at first they all scattered in 

 disorder; but he soon noticed that if an individual in the 

 course of his peregrinations discovered an outlet, he re- 

 turned to the midst of the others ; of these he touched a 

 certaija number, and after this mimic communication the 

 whole population assembled in regular lines, which marched 

 out under the impulse of one common thought — that of 

 liberty regained. 



In all the large animals there are but two ej^es; in this 

 respect the smallest insect is infinitely better provided than 

 they are. The ant, the visual apparatus of which is one 

 of the least perfect, possesses fifty. The common fly has 

 8000, and in certain butterflies as many as 25,000 have 

 been counted. Each of these organs, too, presents, in 

 microscopic proportions, the greatest part of the structures 

 Avliich enter into the composition of the globe of our eye. 

 Closely packed together, these eyes make up for their 

 immobility by their bulk, and this is so great that in some 

 flies it almost covers the head, and even constitutes a 

 fourth part of the weight of the body. 



This powerful optic apparatus exhibits some curious 

 modifications which reveal the habits of insects. 



Those Avhich seek their prey by night have their eyes 

 more deeply set, in order better to absorb the least lumin- 

 ous rays. In the flesh-eating insects they are larger. In 

 some aquatic species the head is furnished with several 

 pairs, some directed upwards, others downward, in such a 

 way, that Avhile swimming on the surface of the water the 



