04 THE STORY OF THE BIRDS. 
mental literature—the constancy of the dove group 
will not bear too close inspection, since even Aristotle 
denied it so long ago, and 
his views have been con- 
firmed by others. 
Mr. Darwin thought 
also that perhaps in 
more instances than 
is usually suspected 
birds were  associ- 
ated in triplets— 
two of one sex with 
one of the other— 
and he instances some, 
and that this was a 
loose union — easily 
broken when a better 
situation was open. 
Such things are noticeable 
among domestic geese, ete. 
The writer recently received a letter from a Nebraska 
observer, asking why he so frequently saw three crows 
together in nesting season; and he went on to say 
that there was a song about “three black crows,” 
probably founded on a similar basis. But he omitted 
his address (and a stamp of course), so that he could 
never be answered from this source, unless this little 
book falls into his hands and gives him the above 
inkling. 
Birds may change their habits with regard to de- 
votion to mates with change of environment. The 

Daw. 
