SMITHSONIAN 



CONTRIBUTIONS TO KNOWLEDGE. 



YOL. XVII. 



EVEUY MAN IS A VALUABLE MEMBER OK SOCIETY, WIIO, BY HIS OBSERVATIONS, RESEARCHES, AND EXPERIMENTS, TROCUKKS 



KNOWLEDGE FOR MEN. SMITUSON. 



CITY OF WASHINGTON: 



PUBLISHED BY THE SMITHSONIAN INSTITUTION. 



JIDCCCLXXI. 



mi 



