INCOMPETENT COW-BIRDS 201 



does with cattle, whence its scientific and popular 

 names. Like the rest of the genus, it is chiefly 

 a ground-bird and a walker, so that in general 

 habits it presents no resemblance whatever to the 

 parasitic Cuckoos. 



In South America are found several species, and 

 it is to the able historian of the birds of Argentina 

 Mr. W. H. Hudson, that we owe the elucidation of 

 their curious half- developed instincts. The best- 

 known species, the glossy Cow-bird (Molobrus bonar- 

 iensis), is very common and often imported here 

 as a cage-bird ; the male is a resplendent purple 

 and the hen sooty. It is truly parasitic in that its 

 young are always reared by other birds, but its 

 parasitism is slovenly and incomplete. Several 

 females will lay in the same foster-nest, and fairly 

 swamp it with their undesired contributions, 

 whereas it is rare in the case of the Cuckoo to 

 find, two parasite eggs in one nest. To this suicidal 

 instinct they add another equally silly, of destroying 

 any sort of eggs they may come across, those of 

 their own species included ; and moreover they 

 recklessly drop eggs about on the ground, a habit 

 shared by another South American bird, the Rhea. 

 And just as the hen Rheas are, so to speak, parasitic 

 on their own males, and pool their eggs in his nest, 

 so these hen Cow- birds occasionally make a futile 

 nest of their own, in some silly place such as on 

 the leaves of a large thistle, and leave even this 

 poor attempt unfinished. 



Then there is a species, brown with chestnut 



