128 BIRDS OF LA PLATA 



salt-lake which, however, had been abandoned by 

 the birds before my visit* The nest there, as in other 

 regions, was a small pillar of mud raised a foot or 

 eighteen inches above the surface of the water, and 

 with a slight hollow on the top ; and I was assured 

 by people who had watched them on their nests that 

 the incubating bird invariably sits with the hind 

 part of the body projecting from the nest, and the 

 long legs dangling down in the water, and not tucked 

 up under the bird* 



On the Rio Negro I found the birds most abundant 

 in winter, which surprised me, for that there is a 

 movement of Flamingoes to the north in the autumn 

 I am quite sure, having often seen them passing 

 overhead in a northerly direction in the migrating 

 season, I have also found the young birds, in the 

 grey plumage, at this season in the marshes near to 

 Buenos Ayres city, hundreds of miles from any 

 known breeding-place. Probably the birds in the 

 interior of the country, where the cold is far more 

 intense than on the sea-coast, go north before winter, 

 while those in the district bordering on the Atlantic 

 have become stationary. 



The Flamingo has a curious way of feeding : it 

 immerses the beak, and by means of a rapid con- 

 tinuous movement of the mandibles passes a current 

 of water through the mouth, where the minutest 

 insects and particles of floating matter are arrested 

 by the teeth. The stomach is small, and is usually 

 found to contain a pulpy mass of greenish-coloured 

 stuff, mixed with minute particles of quartz. Yet 



