i8o BIRDS OF LA PLATA 



prey generally. Its noisy cry and irascible temper 

 are spoken of by most travellers and naturalists ; 

 for no person riding across the pampas could possibly 

 overlook the bird, with its screaming protests against 

 all trespassers perpetually ringing in his ears ; but 

 they have all omitted to mention the singular habit 

 which this bird has of associating in sets of three 

 for the purpose of amusement or play. Each couple, 

 as I have said, live always together on their own 

 pretty well - defined plot of ground, which they 

 jealously guard from intrusion. Yet if you watch 

 a pair of them for a while you will presently see 

 another bird one of a neighbouring couple rise 

 up and fly to them, leaving his own mate to take care 

 of home ; and instead of resenting this visit as an 

 intrusion, they welcome it with notes and signs of 

 manifest pleasure. Advancing to the visitor, they 

 place themselves behind it, and then all three, keeping 

 step, begin a rapid march, uttering loud drumming 

 and rhythmical notes in time with their movements, 

 the notes of the birds behind coming in a rapid 

 stream, while the leading bird utters loud single notes 

 at regular intervals. The march ceases, the leader 

 stretches out his wings, still emitting loud notes, 

 while the other two, with puffed-out plumage, 

 standing exactly abreast, stoop forward until the 

 tips of their beaks touch the ground, and, sinking 

 their voices to a murmur, remain for some time in 

 this singular posture. The performance is then over ; 

 the birds all resume their natural attitudes, and the 

 visitor takes his leave. It is quite certain that this 



