212 THE PLAY OF ANIMALS. 



game, while the air for kilometres around vibrates with 

 their harsh, metallic cries. Most ducks confine their 

 play to mock battles on the water, but the beautiful 

 whistling duck of La Plata conducts them on the wing 

 as well. From ten to twenty of them rise in the air until 

 they appear like a tiny speck, or entirely disappear. 

 At this great height they often remain for hours in one 

 place, slowly separating and coming together again, 

 while the high, clear whistle of the male blends admira- 

 bly with the female's deeper, measured note, and when 

 they approach they strike one another so powerfully with 

 their wings that the sound, which is like hand-clapping, 

 remains audible when the birds are out of sight. The 

 most beautiful member of the quail family found in La 

 Plata is the ypecaha — a fine, strong bird about the size 

 of a hen. A number of them choose a rendezvous near 

 the water. One raises a loud cry three times from the 

 reeds near this spot, and the invitation is quickly re- 

 sponded to by the other birds, who hasten thither from 

 every direction till ten or twenty are collected. Then 

 the performance, which consists in a frightful concert 

 of screams, begins in tones that are strongly suggestive 

 of the human voice when it expresses extreme terror 

 or agonizing pain. A long, penetrating cry of aston- 

 ishing force and violence follows the deeper tones as 

 though the creature would exhaust all its strength in 

 this alarm. Sometimes this double call is repeated and 

 is accompanied by other sounds that resemble half- 

 smothered groans, and all the while the birds run about 

 as if possessed, their wings outstretched, their beaks 

 wide open and held up. After two or three minutes 

 the company quietly breaks up. 



Jacanas, strange birds with peculiar cockscomblike 

 head decorations, spurs on their wings, and long, thin 



