DIFFERENT KINDS OF INSTINCT. Ill 



vation only in some points of secondary importance. They 

 do not invent ; they only modify the suggestions of instinct, 

 from absolute necessity. The first society of bees constructed 

 their cells as perfectly as is now done ; they have never im- 

 proved ; but the first man had no shelter but such as the foli- 

 age of a tree could afford him. 



' In considering the facts which are known with regard to 

 instinct, they may be arranged under two heads ; the first ex- 

 hibiting examples of pure instinct; and the second, of such 

 instincts as can accommodate themselves to peculiar circum- 

 stances and situations, or such as are improvable by experience 

 and observation.' 



1. Of Pure Instincts. 



By pure instincts are meant those, which, independent ol 

 all instruction and experience, instantaneously produce cer- 

 tain actions when peculiar objects are presented to animals, 

 or when they are influenced by peculiar feelings. Of this 

 class the following are examples. 



In the human species, the instinct of sucking is exerted 

 immediately after birth. This instinct is not excited by any 

 smell peculiar to the mother, to milk, or to any other sub- 

 stance ; for infants suck indiscriminately every thing brought 

 into contact with their mouths. The desire of sucking, there- 

 fore, is innate, and coeval with the appetite for air. 



When caterpillars are shaken off a tree in every direction, 

 all of them instantly turn toward the trunk, and climb up, 

 though they have never formerly been on the surface of the 

 ground. 



Young birds open their mouths upon hearing any kind of 

 noise, as well as that of their mother's voice. They have no 

 apprehensions of harm ; neither do they offer to use their 

 wings till they acquire more strength and experience. The 

 lion's cub is not ferocious till he feels force and activity for 

 destruction. 



Insects invariably deposit their eggs in situations most 

 favorable for hatching and affording nourishment to then- 

 future progeny. Butterflies, and other insects, whose offspring 

 feed upon vegetables, uniformly fix their eggs upon such 

 plants as are most agreeable to the palate and constitution of 

 their young. Water insects never deposit their eggs on dry 

 ground. Butterflies, which have been transformed in the 



