MONKEYS AND THE FEAR OF SNAKES. 347 



18. Monkejs and tbe Fear of Snakes. By P. Chalmers 

 Mitchell, D.Sc, LL.D., F.R.S., CbI^E., Secretary of 

 the Society. 



[Received March 21, 1920: Road Mavch 21, 1922.] 



"When I became Secretary of the Society, the practice of 

 feeding Hve animals to snakes was violently attacked, on the 

 ground of cruelty, and vigorously defended as natural and 

 necessary. I enquired into the attack and the defence. The 

 latter was easily disposed of. I could not agree that even if 

 cruelty were part of the order of Nature we were justified in 

 continuing it under artificial conditions. Nor could I accept the 

 odd opinion urged on me in particular by the late Dr. Plimmer 

 that there was merit in the flesh of prey killed by the serpent 

 itself, absent from prey killed by other means. But the question 

 was answered by practice. Mr. E. G. Boulenger, our Curator of 

 Reptiles, to whom I am much indebted for his patient and 

 ■careful observation of my suggestions, is now in agreement 

 with me that snakes do not require a living prey. 



The cruelty .dleged by the attack is a more difiicult, and from 

 the scientific point of view, more interesting question. So far as 

 I could see, frogs, rats and mice, rabbits, guinea-pigs, fowls and 

 ducks, introduced to snakes, had no sense of impending fate, and 

 treated the creatures which were going to destroy them as 

 indifferent objects. The sense of terror was in the spectators, 

 not in the victims. But I wished to carry the matter further, and, 

 with the assistance of Mr. R. I. Pocock, the Society's Curator of 

 Mammals, made a large series of experiments by introducing 

 live snakes to different kinds of animals. The results of these 

 ■observations have already been communicated to the Society 

 (P. Z. S. 1907, p. 785), and I have also repeated some of the 

 actual experiments at one of our Scientific Meetings. Except 

 in the cases of a few of the higher birds, notably parrots and 

 Passerines, and the Primates excluding Lemurs, animals show no 

 special relation of fear in the presence of living snakes, even 

 when the latter are allowed to approach them closely, protruding 

 their quivering tongues. But the reaction of fear is immediate 

 and painful to see when a snake is introduced to a parrot or 

 starling in a cage, or to anjr of the true monkeys from the South 

 American marmosets to the Great Apes. 



The instant recognition and betrayal of fear by special sounds 

 and rapid retreat, even in the case of a lethargic old Orang-utan, 

 were so plain that I was disposed to treat them as instinctive, 

 -and even went the length of suggesting tliat the human dread of 

 ■snakes might be an instinct inherited from our ape-like ancestors. 



