WINGS AND FEET 



flight, as witness the great auk and pen- 

 guins. 



3d. That specialization towards the use of 

 the feet alone is probably best adapted for the 

 most rapid progression under water, and this 

 method may leave the wings undiminished in 

 size for use in the air. The apparent exception, 

 hesperornis, with powerful feet but with wings 

 degenerated to vestiges through disuse, serves 

 but to confirm the inference of the superiority 

 under water of feet action alone. 



205 



