SONGS OF BIRDS. 357 
markable deviations occur in species otherwise 
pretty uniform in their “ love-notes” ? how also can 
we account for these same pretended invitations 
and devotions occurring in some species at other 
seasons besides in that of love, and that these notes 
also are greatly influenced by weather, as I intend 
presently to shew? ‘That song-birds possess the 
faculty of music in various degrees according to the 
species, is shewn by the superior ability displayed by 
some caged birds over othersin the acquisition of new 
notes better even than those of their kindred ; fin 
the wild state, the Linnet is an instance of this. 
But the organic apparatuses subservient to mental! 
faculties, ever display in greater or less degree, 
conformity of structure to differences of actual 
power. The larynges and trachee of song-birds 
and of those not musical exhibit according disagree- 
ments and minor differences have even been pointed 
out. Now such elaborations of mechanism and 
structure would hardly have been ordained as the 
instruments for conveying amorous and temporary 
intelligences. Hen birds which through altered 
food and modes of life acquire male characters, 
have been known to sing, which is a reversion of 
presumed order in the matter of love. 
By some few naturalists, songs of birds were 
thought to be dependant on imitation, the young 
invariably deriving their notes from their parents, 
a notion scarcely deserving serious refutation. By 
others these sounds have been ascribed to rivalry, 
and though it is ridiculous to consider them as 
solely dependant on this feeling, there is no doubt 
that some variations of their songs are thus excited. 
Some persons consider that food has considerable 
power in the production of song, and though I feel 
no hesitation in assenting to this from observing 
the effects of plenty of food in producing extraor- 
dinary aptitude for singing in caged birds, and from 
