68 BIRDS OF LA PLATA 
In August they begin to sing, here and there an 
individual being heard in the fields; but when the 
weather grows warmer they repair to the plantations 
in vast numbers, and, sitting on the branches, 
sing in a concert of innumerable voices, which 
produces a great volume of confused sound, and 
which often continues for hours at a time without 
intermission. 
By-and-by these pleasant choirs break up, the 
birds all scattering over the plains and fields to woo 
and build, and it is then first discovered that the 
male has a peculiar and very sweet song. Apart from 
his fellows he acquires a different manner of singing, 
soaring up from his stand on the summit of a bush or 
stalk, and beginning his song the moment he quits 
his perch. Ascending he utters a series of long 
melodious notes, not loud but very distinctly enun- 
ciated and increasing in volume ; at a height of fifty 
or sixty yards he pauses, the notes becoming slower ; 
then, as he descends with a graceful flight, the wings 
outstretched and motionless, the notes also. fall, 
becoming slower, sweeter, and more impressive till 
he reaches the earth. After alighting he continues 
the song, the notes growing longer, thinner, and 
clearer, until they dwindle to the merest threads of 
sound, and cease to be audible except to a person 
standing within a few yards of the singer. The song 
is quite unique in character, and its great charm is in 
its gradual progress from the somewhat thick notes 
at the commencement to the thin, tremulous tones 
with which the bird returns to earth, and which 
