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. 



