CONTENTS 



Original Papers 



Page 

 Physics. — The size and shape of the electron. Arthur H. Compton 1 



Chemistry. — A silica-glass mercury still. J. C. Hostetter and R. B. 



SOSMAN 11 



Physiology. — Sensory fibers in the mesencephalic root of man and the guinea 

 pig. William F. Allen 15 



Conchology. — The land mollusks of the genus Obba from the islands of Bohol 

 and Panglao, P. I. Paul Bartsch 16 



Abstracts 



Geology 18 



Parasitology 19 



Proceedings 



Washington Academy of Sciences 20 



Anthropological Society 21 



Biological Society 25 



