CONTENTS 



Original Papers 



Page 

 Meteorology. — The unusual atmospheric haziness during the latter part of 



1912. H. H. Kimball 269 



Physiq^. — Recent theories of heat and radiation. W. Wien 273 



Radiotelegraphy. — A comparison of arc and spark sending apparatus for 



radiotelegraphy. L. W. Austin 284 



Mineralogy. — Triplite from eastern Nevada. Frank L. Hess and W. F. 



Hunt 286 



Helminthology. — Notes on Monochus and Tylenchulus. N. A. Cobb 287 



Vital Statistics. — A natural population norm. II-V. Alfred J. Lotka 289 



Abstrac'ts 



Botany 294 



Zoology ■ ^ 294 



Ichthyology . , 295 



Proceedings 



-"'The Philosophical Society of Washington ■; 29G 



The Geological Society of Washington '. . . 300 



The Anthropological Society of Washington 304 



