THE PHANTOMS BEHIND US 
processes, or the evolutionary processes; they are 
formed on the pattern of our own brief span of life. 
In a few cases in the familiar life about us we see the 
evolutionary process abridged, and transformations 
like those of unrecorded time take place before our 
eyes, as when the tadpole becomes the frog or the 
grub becomes the butterfly. These rapid changes 
are analogous to those which in the depths of geo- 
logic time have evolved the bird from the fish or the 
reptile, or the seal and the manatee from a four- 
footed land animal. Our common bluebird has long 
been recognized as a descendant of thethrushfamily; 
this origin is evident in the speckled breast of the 
young birds and in the voices of the mature birds. 
T have heard a bluebird with an unmistakable thrush 
note. The transformation thas doubtless been so 
slow that an analogous change taking place in any 
of the bird forms of our own time would entirely 
escape observation. The ‘bluebird may have been 
as long in getting his blue coat as man has been in 
getting his upright position. 
Looking into the laws and processes of the com- 
mon nature about us for clues to the origin of man 
is not unlike looking into the records of the phono- 
graph for the secret of the music which that won- 
derful instrument voices for us. Something, some 
active principle or agent, has to invoke the music 
that slumbers or is latent in thése lines. 
In like manner some principle or force that we 
201 
