The Wood hewer Family. 
257 
FurnariLis, and it is very curious that the young 
birds, when only partially fledged, are constantly 
heard in the nest or oven apparently practising 
these duets in the intervals when the parents are 
absent; single measured notes, triplets, and long con- 
cluding trills are all repeated with wonderful fidelity, 
although these notes are in character utterly unlike 
the hunger cry, which is like that of other fledglings. 
I cannot help thinking that this fact of the young 
birds beo’innino' to sing like the adults, while still 
confined in their dark cradle, is one of very con- 
siderable significance, especially when we consider 
the singular character of the performance; and 
that it might even be found to throw some light on 
the obscure question of the comparative antiquity of 
the different and widely separated Dendrocolaptine 
groups. It is a doctrine in evolutionary science 
that the early maturing of instincts in the young 
indicates a high antiquity for the species or group ; 
and there is no reason why this principle should 
not be extended, in the case of birds at any rate, to 
language. It is true that Daines Barrington’s 
notion that young song-birds learn to sing only by 
imitating the adults still holds its ground ; and 
Darwin gives it his approval in his Descent of 
Man. Ifc is perhaps one of those doctrines which 
are partially true, or which do not contain the 
whole truth ; and it is possible to believe that, while 
many singing birds do so learn their songs, or 
acquire a greater proficiency in them from hearino- 
the adults, in other species the song comes instinc- 
tively, and is, like other instincts and habits, purely 
an inherited memory.’^ 
