3672 Reptiles. 



where the head of a rattlesnake so engaged was sideways to the glass 

 of the cage, and near it, I observed, and called attention to the fact, a 

 remarkable vermicular motion along the course of the poison-gland to 

 the opening of the angle of the mouth, which we thought might afford 

 him pleasure, and this continued until the snake struck his prey. All 

 these serpents seem to prefer striking when the animal is about a foot 

 distant; when directly under and close to the head they would not 

 strike. The blow itself was very rapid ; and although the united pur- 

 pose of five observers was to detect the spot where the wound was 

 inflicted, it was seldom any one succeeded. The puff-adders at first 

 hissed violently, and swelled to double their usual thickness ; one of 

 them struck at us, but was foiled by the intervening glass. The co- 

 bras raised themselves and spread out their beautiful hoods. The 

 rattlesnakes retired and then advanced, but emitted no sound ; and 

 the one that did not bite soon returned to his former passive condi- 

 tion. The bite of the rattlesnake, as will be seen, caused the most 

 speedy death. 



So far the serpents. I now proceed to describe the peculiarities 

 shown by the animals on which we experimented. Some philosophers 

 have denied innate ideas to man ; these and some others have further- 

 more denied an instinctive apprehension of danger in animals. They 

 say that of itself, as born, the hare has no dread of the hound ; that 

 its fear is acquired of experience. I concur in neither of these 

 opinions, and think the latter altogether refuted by the conduct of the 

 animals exposed to serpents in these experiments. Not one of the 

 guinea-pigs or rabbits (which were all something under their full 

 growth) had ever seen a serpent, yet when introduced to the cage they 

 showed unequivocal symptoms of distress and fear. In some instan- 

 ces they actually screamed before they were struck. They generally 

 showed restlessness at first, but when the serpent, intending to strike, 

 poised himself in front, they became for a time, if not altogether, mo- 

 tionless. Is there such a thing as " fascination ? " If by this is 

 meant a pleasurable paralysis of the animal's powers, I think it more 

 than doubtful ; but a deprivation of the power of motion from terror 

 may, perhaps, take place. All, however, that I speak to is a perfectly 

 motionless condition of snake and prey, lasting several minutes. In 

 one case, however, a rabbit (without being compelled by us to move 

 and aggravate the serpent, for our exhausted patience necessitated the 

 hurrying of the bite) in the course of a few minutes seemed to forget 

 its danger, sat up like a squirrel, rubbed its face with its paws, and 

 moved indifferently about the cage, treading upon other snakes 



