nn STORY OF, THE. BIRDS. 
CHAPTER “TI. 
A BIRD’S FOREFATHERS. 
Tue birds form one of the five great groups of 
the vertebrates, and of course their ancestry began 
when the backbone was a gristly cord on the lower 
border of the fishes. Perhaps we might begin later, 
when the backbone of the higher fish-forms had be- 
come bony and jointed and a brain case had expanded 
upon its forward end; for birds are certainly brainy 
creatures. Later still) we might set our beginning 
when the numerous rays of the fins of fishes gave 
way to the few fingers and toes of the four-footed, 
land-tending amphibians, and where the fringed gill 
of the water breather yielded to the simple lung sae 
of the air breather; for our bird has certainly four 
limbs only, with few fingers and toes on each, and it 
is the best adapted to air breathing of all earth’s 
creatures. Or possibly our story might begin at that 
point where the young ceased to have a tadpole or 
larval state, but began at once to resemble its parents 
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