CONTENTS 
Page. 
PERKINS, GRANVILLE A. The expression of the octet 
theory of valence in structural formulas .. 1 
LIGHT, S. F. Notes on Philippine Termites, II 23 
STAPF, 0. A new species of Vincentia from the Philip- 
pines 65 
WELLS, A. H. The preparation of tikitiki extract for 
the treatment of beriberi 67 
ROHWER, S. A. The Philippine wasps of the sub- 
families Scoliinse and Elidinse.. 75 
REINKING, OTTO A. Higher Basidiomycetes from the 
Philippines and their hosts, V ..' 91 
McLEAN, F. T. The permeability of Citrus leaves to 
water . ' 115 
REVIEWS _...... r 127 
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