362 : FLAMINGOES, DUCKS, AND SCREAMERS., 
with a whitish tip, the horn whitish grey, and the foot ashy grey. The second 
genus, Chauwna, has no horn on the head, and is represented by the crested 
screamer, or chaj& (C. chavaria) of Argentina, and the Derbian screamer 
(C. derbiana) of Colombia. In the former the general colour of the plumage is 
slaty blue, with a black ring round the neck, while the naked skin round the eyes 
and the legs are red. According to Mr. W. H. Hudson, to whom we are indebted 
for a good account of the Argentine species, these birds only utter their powerful 
scream of alarm occasionally ; while during the night, or when soaring high in the 
air, they give vent to somewhat melodious notes, audible when the birds are too 
high up to be visible. “At certain times,” writes the author just mentioned, “in | 
districts favourable to them, the chajas often assemble in immense flocks, thousands 
of individuals being sometimes seen congregated together; and in these gatherings 
the birds often all sing in concert. They invariably—though without rising— 
sing at intervals throughout the night, ‘counting the hours, as the Gauchos say, 
the first song being about nine o'clock, the second at midnight, and the third just 
before dawn, but the hours vary in different districts.’ Although living for 
a considerable part of the year in large flocks, the screamers pair for life, and 
during the breeding-season are only to be seen in couples. The chaja (pronounced 
chaha), or Argentine species, breeds among the rushes of lagoons, and during a 
visit to Argentina in 1893, I had, while staying at the estancia of Las Bandurrias, 
near Colina, on the Great Southern Railway of Buenos Aires, the opportunity of 
observing the habits of a pair which were nesting in a small laguna a couple 
of miles or so from the house. The laguna in question contained large growths of 
reeds and flags, forming masses intersected by open channels, and at the time of 
my visit (the latter part of October) growing to a considerable height above the 
water. Like other similar spots in this part of Argentina, it was tenanted by 
large flocks of ducks and coots, while black-necked swans. small parties of the 
lovely red South-American flamingo, and a few storks were generally also to be 
seen. On my first visit to the laguna, for the purpose of duck-shooting, I was 
puzzled by seeing a pair of large grey birds, with short beaks, and looking some- 
what like huge grey geese, swimming about unconcernedly among the other 
denizens of the lagoon, since I had not the least idea such was the habit of the 
chaja. On wading into the water, and approaching the birds, I was, however, soon 
convinced, both from their appearance and voice, that they were really chajas. 
They allowed me to approach within easy gun-shot, when they rose heavily and 
flapped slowly to the bank, where they alighted. That they had a nest among the 
reeds in the middle of the laguna I felt assured, but the depth of water prevented 
my wading to the spot. I had, however, reason to believe that the young were 
already hatched and swimming about among the reeds, so that, had I sueceeded in 
reaching the nest, my labour would have been in vain. As soon as I reached the 
shore, the chajas once more returned to the water, and recommenced swimming 
about among the ducks. During several subsequent visits to the same spot, I 
nearly always saw the birds swimming far out in the water; and, indeed, I think 
it was only once or twice that I observed them on land. It is therefore evident 
that during the nesting-season this pair of chajas should be described as thoroughly 
aquatic in their habits. 
