Wings 321 
each of which has ten primaries, but the one has six and 
the other forty secondaries (Figs. 259, 260).* 
Let us observe the wings of living birds in the woods 
and fields or in a zoological park and see what of interest 
we can discover. We have all noticed how well adapted 
Fig. 256.—Great White Heron stretching its wing. (E. R. Sanborn, 
photographer. ) 
to its owner’s many uses is the foot of a parrot—how 
hand-like it is,—and now if we again watch one of these 
birds we will see that, as we should expect from its being 
* Extremes in regard to the number of primaries are the three flightless 
groups, penguins with approximately 36, ostriches with 16, and cassowaries 
with perhaps but 2 feathers which can be called primaries. 
