SELF-PRESERVATION. 137 



nervous system, having all the characteristics of a fundamental faculty. It con- 

 sists in an impression purely instinctive, which prompts animals to fly or to keep 

 themselves on their guard, when any external circumstances appear to threaten 

 their existence: This faculty is one of those which manifest themselves at an 

 early period in animals. I am disposed to believe, that to it must be ascribed 

 the squalling of the infant when newly born, and the cries which young animals 

 emit when some unexpected object alarms them. It was the sudden disappear- 

 ance of certain species at the least noise, or at the aspect of an object which they 

 saw for the first time, which led me to entertain the idea that their manner of 

 acting in this case might depend on a fundamental faculty. I had seen Foxes, 

 Rats, Mice, Cats, disappear with the rapidity of lightning, at the unexpected 

 sight of a person^ or on hearing an unwonted sound. Whence, said I, can such a 

 mode of action arise ? What can cause these animals to apprehend that their life 

 is in danger, since many of them have never experienced anything which can lead 

 them to entertain any dread from these external occurrences ? Nevertheless, 

 their first action is to fly. 



In the beginning of my enquiries, and for a considerable time, I entertained 

 the opinion that the conduct of these animals might depend on a considerable 

 development of Secretiveness or Cautiousness, but numerous observations des- 

 troyed this supposition. Experience demonstrated to me, that animals pos- 

 ssessing little Secretiveness and little Cautiousness, allowed nobody to ap- 

 proach them without great difficulty, and had a singular tendency to fly or to 

 preserve themselves. As observations made on individuals of the same species 

 were best adapted for reaching the truth, I devoted myself to the study of the 

 habits of several animals which I reared under my own eyes, and to keeping an 

 exact account of their most remarkable faculties. From 1824 to 1825, 1 observed 

 with care the conduct and actions of a dozen Rabbits, the offspring of the same 

 mother. I used to set them at liberty twice a week in a garden, and to dedicate 

 two hours to surveying them. One of them struck me more than all the others, 

 by the habit which it had of flying with astonishing rapidity every time I ap- 

 proached it ; it would scarcely be believed how frequently I saw it strike the 

 ground suddenly with its paws, probably to give notice to its companions, and 

 then instantly disappear. Nevertheless it was neither more cunning nor more 

 circumspect than the others; it was even one which was seized most easily 

 when I wished to put them into their boxes ; I had, on the contrary, great trou- 

 ble in catching several others, which succeeded in avoiding me by a thousand 

 detours. What, then, I asked myself, can give to this animal the idea of flying 

 with such rapidity ? Why, then, is there in this respect so great a difference 

 among twelve animals produced by the same mother, and all under the influence 

 of the same external circumstances ? Without doubt all these animals have a 



