CONTENTS 



Page 



Originai. Papers 



Physics — Methods of increasing the precision of thermostats. Walter P. 



White 429 



Botansr — A new genus of Leguminosae. C. V. Piper 432 



Entomologj' — Descriptions of two new species of butterflies from tropical 



America. W. Schaus 434 



Thermochemistry — The thermochemistry of ionization of vapors of certain 



compounds. Paul D. FooTE and F. L. Mohler 435 



Proceedings 

 Entomological Society of Washington 445 



Scientific Notes and News 449 



