xii LIST OP ILLUSTRATIONS. 



FIG. PAGE 



2!i. Curved bill of female, straight bill of male Huia-bird . . 3a 



23. Feathers from back of Snowflake, showing seasonal changes in 



form and color due to wearing off of tips . . . .38 



34. Eggs of (a) Spotted Sandpiper and (4) Catbird, to show differ- 

 ence in size of eggs of prajcocial and altricial birds of same 

 size 68 



25. Topography of a bird ......... 7i 



