Music and Dancing mn Nature. 267 
note of invitation, quickly responded to by other 
birds from all sides as they hurriedly repair to the 
usual place. In a few moments they appear, to the 
number of a dozen or twenty, bursting from the 
rushes and running into the open space, and 
instantly beginning the performance. This is a 
tremendous screaming concert. The screams they 
utter have a certain resemblance to the human 

Dance of Ypecaha Rails. 
voice, exerted to its utmost pitch and expressive 
of extreme terror, frenzy, and despair. A long, 
piercing shriek, astonishing for its vehemence and 
power, is succeeded by a lower note, as if in the 
first the creature had well nigh exhausted itself: 
this double scream is repeated several times, and 
followed by other sounds, resembling, as they rise 
and fall, half smothered cries of pains and moans 
of anguish, Suddenly the unearthly shricks are 
