A LITTLE TALK ON BIRDS’ TOES. 16% 
ing things that bear on their story, but we can only 
glance at them. Beyond what in them seems to be 
the ankle (though really at the knuckles in our hand) 
the bones that were separate in the reptiles are fused 
together to form a stiff, slim, light, swiftly moving 
shank (tarsus), a condition brought about in most oth- 
er creatures at the 
demands of speed 
afoot. So also in 
most birds, except 
penguins (and in an 
occasional ee Foot of cormorant—a typical diver—show- 
anywhere), the small- ing prestige of outer toe. 
er bone (fibula) of 
the next joint (drumstick) is partly gone or much fused 
to the other (#bza). Since the reptiles and Arche- 
opteryx have this bone complete and separate, it seems 
hard to resist the impression that this arrangement 
also was brought about for speed while running, and 
that all birds except penguins have come from ances- 
tors that once became terrestrial after having acquired 
flight. There are some other things that bear in the 
same direction, but we shall have to forego them. 
Returning to the bird’s toes in this connection, 
it is evident that the rear or first one, when lost, is 
always lost in connection with terrestrial or at least 
nonperching habits; and so far as we can note its 
gradations, it always tends to be opposable and ele- 
vated before going. 
Perhaps in nothing about a bird’s toes lies more 
of its history than in the tendons that flex each one 

