162 PHYSIOLOGY. 







15j{ In animals, the organ of touch varies. In the ape 

 tribe it is similar to that of man. In some quadrupeds it 

 is seated in the lips, snout, or proboscis, as in the horse, the 

 hog, the mole, the rhinoceros, and the elephant. Indeed, 

 the trunk of the elephant comes very near to the human 

 hand in nicety of touch, and delicacy of perception. The 

 bat is remarkable for sensibility of touch. It has been found 

 that if its eyes were destroyed and its ears and nostrils shut 

 up, it would fly through intricate passages, without striking 

 against the walls, and avoid every object placed in its way. 

 This faculty is supposed to be owing to the great delicacy of 

 touch residing in the membrane of the wings, which feels 

 instantaneously any change produced in the resistance of the 

 air. 



16.1 Ig insects, the antenna or feelers, are the organs of 

 touch. These are of a great variety of forms, very flexible ; 

 and constantly in motion, when the insect is walking. If 

 the feelers of an insect are cut off, it either remains motion- 

 less, or if it attempts to fly, it appears bewildered and lost. 

 It is by means of their feelers that bees are able to work in 

 a hive without light, and build their cells with the greatest 

 regularity ; by them also, they communicate to one another 

 their impressions and their wants. | 



17. It is supposed that the different modes in which ants 

 touch each other with their feelers, when they happen to 

 meet, constitutes a kind of natural language, understood by 

 the whole tribe. It is evident that they could not co-operate 

 in their labours without some kind of language. When an 

 alarm is given in time of danger, one ant strikes his head 

 against the corselet of every ant which it chances to meet, 

 and these repeat the same act to all that fall in their way, 

 and so the news is quickly spread through the whole societyjf 



18. Sentinels are always placed on the outside of ants' 

 nests to apprize the inhabitants of any danger. When an 

 enemy approaches, these guardians quickly enter the nest 

 and spread the news in the way just stated, and soon the 



