SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOLUME 57, NUMBER 3 



CAMBRIAN 

 GEOLOGY AND PALEONTOLOGY 



No. 3.— MIDDLE CAMBRIAN HOLOTHURIANS 

 AND MEDUS/E 



With Six Plates 



BY 



CHARLES D. WALCOTT 



( Publication 2011 ) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



JUNE 13, 1911 



