Wings 321 



each of which has ten primaries, but the one has six and 

 the other fort}' secondaries (Figs. 259, 260).* 



Let us observe the wings of Uving birds in the woods 

 and fields or in a zoological park and see what of interest 

 we can discover. We have all noticed how w^ell 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 w^e 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. 



