262 The Naturalist in La Plata. 
begins a series of movements as if dancing a 
minuet ; finalljj carried away with excitement^ be 
leaps and gyrates in the most astonishing manner, 
until, becoming exhausted, he retires, and another 
bird takes his place. 
Tn other species all the birds in a company unite 
in the set performances, and seem to obey an impulse 
which affects them simultaneously and in the same 
degree; but sometimes one bird prompts the others 
and takes a principal part. One of the most curious 
instances I have come across in reading is contained 
in Mr. Bigg- Wither’s Pioneering in South Brazil. 
He relates that one morning in the dense forest 
his attention was roused by the unwonted sound 
of a bird singing — songsters being rare in that 
district. His men, immediately they caught the 
sound, invited him to follow them, hinting that he 
would probably witness a very curious sight. 
Cautiously making their way through the dense 
undergrowth, they finally came in sight of a small 
stony spot of ground, at the end of a tiny glade ; 
and on this spot, some on the stone and some on 
the shrubs, were assembled a number of little birds, 
about the size of tom-tits, with lovely blue plumage 
and red top-knots. One was perched quite still on 
a twig, singing merrily, while the others were keep- 
ing time whh wings and feet in a kind of dance, 
and all twittering an accompaniment. He watched 
them for some time, and was satisfied that they 
were having a ball and concert, and thoroughly en- 
joying themselves ; they then became alarmed, and 
the performance abruptly terminated, the birds all 
going off in different directions. The natives told 
