DERIVA TION OF THE TERRESTRIAL SPHEROID 249 



mountains may be thus likened to the waves of a tempestuous 

 sea, and, within each province of the mightiest rolls, may be 

 arranged in harmony with their taxonomic relationships. 



The master earth ridges may have one origin, and be arrayed 

 — not in sharplv defined geometric figures, perhaps — but in 

 accord with definable laws. Within the grand provinces defined 

 by these greatest features, mountain ranges may be determined 

 by wholly different causes — possibly in out-flowing, curved ele- 

 vations, something after the manner suggested by Suess for 

 Siberia. Parts of these systems may again be modified by still 

 more local causes — being intensified in some places, softened in 

 others. 



In the consideration of mountains, as features of the earth's 

 face susceptible of giving expression to its deepest emotions, we 

 have to recognize fully, before we can hope to understand the 

 riddle of their existence, that all do not possess the same taxo- 

 nomic values. 



Charles R. Keyes. 



Des Moines, Iowa. 



