CONTENTS 
Page, 
LANTIN, PEDRO T. Various methods of serum applica- 
tion in bacillary dysentery... ........... 629 
PERKINS, GRANVILLE A. Unsymmetrical addition 
to the double bond, I: A theory of the reaction 
mechanism of the direct union.. 645 
GROVES, JAMES. Charophyta from Annam and 
Guam 663 
ROLIWER, S. A. The Philippine wasps of the subfamily 
Sphecinse 665 
MERRILL, ELMER D. Two new species of plants from 
Hainan .V.f... 677 
COLE, HOWARD IRVING. The dissociation of hexa- 
phenylethane from the viewpoint of the octet theory 
of valence .u..L.............................. ......................... ..... 681 
McGREGOR, RICHARD C. New or noteworthy Philip- 
pine birds, IV j 691 
BECKER, WILHELM. Die Violen der Philippinen 707 
OKAMOTO, KIKUO. Secondary sexual characters in 
the loach Misgurnus anguillicaudatus Cantor.. 723 
PERKINS, GRANVILLE A. The structure of chlorine 
dioxide and related compounds.... 729 
WELLES, COLIN G. Cercospora leaf spot of coffee.... 741 
WELLES, COLIN G. Cercospora leaf spot of Averrhoa 
earambola 747 
REVIEW 753 
ERRATA 755 
INDEX 757 
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