318 Wonders of the Bird World 



simply by smothering the other young birds with its clumsy 

 weight, and by monopolizing all the food which the old 

 birds bring, so that the other young ones in the nest are 

 gradually starved. 



In South America the habits of the Cow-birds are 

 certainly very curious, and Mr. Hudson gives some re- 

 markable experiences of the nesting of the three species of 

 Molothrus in Argentina, M. bonariensis > M. rufoaxillaris, 

 and M. badins. Though the original account, instructive 

 and wonderful as it is, is too long to be produced in full, a 

 few notes may be given. The Argentine Cow- bird 

 (M. bonariensis) has a dull-coloured hen, and, as in the 

 case of our Cuckoo, the males predominate in number over 

 the females, and the proportion is said by Azara to be 

 that of ten males to every one female. For four months the 

 latter goes on laying eggs, and besides putting several into 

 the nests of other birds, numbers are dropped by her in 

 every direction, and are of course lost for any good that 

 they are. Not only the female herself, but the male also, 

 pecks holes in the eggs of the foster-parents in order to 

 destroy them, but they will also destroy their own eggs in 

 the same manner along with the others, a proceeding which 

 so savours of madness that it is impossible to explain it ; 

 and still more extraordinary, one species of Cow-bird 

 (M. rufoaxillaris] is parasitic on another (M, badius). 

 Whether the Argentine Molothrus bonariensis once made a 

 nest and has gradually abandoned the practice, one cannot 

 say, but Mr. Hudson states that he has twice known the 

 species to make an attempt to do so, but the result was 

 failure in both cases. He thinks it probable that M. 

 bonariensis was once accustomed to build in holes or in 

 covered nests, as both male and female birds take the 

 greatest interest in domed nests, such as those of the Wood- 

 Hewers (Dendrocolaptida], and persistently haunt them and 

 examine them, but never place their eggs there. Mr. 



