174 



ANIMAL BIOLOGY 



Molting. - How do birds arrange their feathers after 

 they have been ruffled ? Do they ever bathe in water? 



FIG. 318. APTERYX, of New Zealand. Size of a hen, wings and tail 



rudimentary, feathers hair-like. 



In dust ? Dust helps to remove old oil. At what season 

 are birds brightest feathered ? Why ? Have you ever seen 



FIG. 319. GOLDEN, SILVER, AND NOBLE PHEASANTS, males. Order? 

 (Key, p. 177.) Ornaments of males, brightest in season of courtship, are due to 

 sexual selection (Figs. 321-7-9, 333). 



evidence of the molting of birds ? Describe the molting 

 process (page 120). 



