20 



EVOLUTION AND ANIMAL LIFE 



FIG. 9. Blunt-nosed salamander, A mblystoma opacum. (Photograph by W. K. Fisher.) 



FIG. 10. White pelicans, Pelecanus erythrorhynchus, and whooping-crane, Grus ameri- 



cana. (Photograph by W. K. Fisher.) 



