THE MEANING OF MUSIC AMONG BIRDS. 81 
in concert at the evident freedom from care that they 
have reached and the prospect of the juicy pulp of 
the farmer’s roasting ear. But this is quite different 
from the wheezy, asthmatic effort by which the male 
in the spring won his wife. 
Likewise the meadow lark has a giggling sort of 
rejoicing which is very different from his true song. 
After molt, many birds sing out of the usual sea- 
son, as if they were conscious of and glad at the ap- 
pearance of a new suit of clothes and at the departure 
of the great physical strain which growing new feath- 
ers entails. 
These are evidences of rejoicing, and no bird sings 
when not well. As to whether a bird sings when sad 
or not, we can surely say that many sing when a mate 
is lost, the song then being a call doubtless purely ; 
but we shall see under Step-parents among Birds 
(Chapter XV) that there is considerable doubt as to 
whether this is intended for the ear of the quick or 
the dead. There is no doubt that songs of some birds 
are simple expressions or overflow of energy, since 
the most nervous and restless, as wrens, finches, 
vireos, ete., sing most tirelessly. A bird may some- 
times sing just as a boy shouts or a girl giggles. 
We have noticed in the last chapter that some 
songs are evident calls to assemblies and combats, as 
the booms of the grouse, and many are challenges and 
_defyings that do not lead always to battle. Bobwhite, 
for instance, sings after mating rather than before it. 
He has a slight tendency to take more than one wife 
sometimes, and with his cry he warns his rival with 
