CONTENTS. 



Page. 



COX, ALVIN J. Philippine Soils and Some of the Fac- 

 tors which Influence Them 279 



HERRMANN, RAF. A Theory on the Formation of the 



Central Luzon Plain 331 



BROOKS, BENJAMIN T. New Philippine Essential 



Oils 333 



EDITORIAL. The Fluctuation in the Value of Ylang- 



Yl^ng Oil and some of Its Causes 355 



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