LITTLE RED HERON in 



But what can one say of such an instinct if we 

 can call it an instinct t It is in its essence a weakness 

 in the creature similar to that of many mammals, 

 birds, fishes, batrachians, reptiles and insects that 

 become paralysed with fear, or rather hypnotised, 

 in the presence of an enemy. A strange flaw in the 

 animal, since it brings to naught all the admirable 

 instincts of self-preservation it has been endowed 

 with, and gives it, without a struggle, a prey to its 

 enemies, even to those of a slow, sluggish disposition. 



In this particular instance the weakness or fault 

 of nature has been taken advantage of by that principle 

 which we call natural selection and has resulted in a 

 more perfect protection than if the bird had been 

 incapable of losing its mind, as one may say. In 

 other words, the creature's liability to the hypnotic 

 or cataleptic state on certain occasions is its best 

 protection. 



This, however, is not the only case in which a 

 seemingly fatal weakness has been turned to good 

 account, as we see in the death-like swoon, or " pre- 

 tending to be dead/' of many creatures when over- 

 come by or in the presence of an enemy. I have 

 observed it in the pampas fox and opossum, in the 

 Tinamu, the Partridge of South America, in our 

 Corncrake, and other Rails, and I have captured 

 small birds by giving them a sudden fright. 



By a strange chance I discovered that my Little 

 Bittern was also subject to this weakness. A gaucho 

 boy of my acquaintance, knowing that I was interested 

 in this bird, one day brought me a dead specimen. 



