. A FEATHERED MIDGET AND ITS NEST. 79 



bird cares nothing for the size or form of the chosen 

 asylum for her young. If it is only large enough for 

 one egg, it is sufficient for her wants, and she forth- 

 with appropriates it to her use without even a "-by 

 your leave" to the rightful owners. And so, very 

 often, among four or five delicate little gnat-catchers, 

 there is found a large chuffy youngster, whose demand 

 for food is incessant, and if supplied in sufficient 

 quantity, he will in a day or two fill the entire nest, 



Fig. 20-Cow-bird. 



and smother beneath his greater bulk the lives of the 

 rightful occupants. It is one of those numerous cases 

 of a struggle for existence in which the most over- 

 bearing, ugliest and strongest survives, instead of the 

 fittest. 



However, I suppose that the modern evolutionist 

 would say, that in this case ugliness and brute strength 

 are necessary qualities of the " fittest," and that nature 

 has ordained that the cow-birds shall increase in num- 



