ORIGIN OF THE LIVING MACHINE: ADAPTATION 343 



habits of life; Figs. 140 to 143. The white fur of the polar 

 bear is an adaptation to its life habits in the north on the ice 

 sheets; for not only does the heavy hair serve as a warm covering 



FIG. 141. THE FOOT OF A BIRD ADAPTED FOR WADING IN MUD 



to protect the animal from the cold, but its color at a distance 

 is hardly to be distinguished from the white ice, and thus pro- 

 tects the bear from observation. The marvelous tongue of the 



FIG. 142. THE FOOT OF A BIRD FIG. 143. THE FOOT OF A BIRD 

 ADAPTED FOR SCRATCHING ADAPTED FOR SWIMMING 



butterfly is adapted for sucking the honey from flowers. The 

 honey in the flower is at the bottom of the long corolla, and 

 unless the butterfly had this long tongue to insert within the 



