SMITHSONIAN MISCELLANEOUS COLLECTIONS 

 VOLUME 139, NUMBER 6 



Claries B. attb JHarp "^Tatix OTalcott 

 &egearcf) Jf tmb 



A REVISION OF THE SILURIAN 

 BRYOZOAN GENUS TREMATOPORA 



(With 2 Plates) 



By 



RICHARD S. BOARDMAN 



Associate Curator of Geology 



United States National Museum 



Smithsonian Institution 



(Publication 4383) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



OCTOBER 29, 1959 



