SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOLUME 89, NUMBER 6 



THE CLASSIFICATION OF THE FREE- 

 LIVING NEMATODES AND THEIR 

 RELATION TO THE PARASITIC 

 NEMATODES 



(With Eight Plates) 



BY 



I. N. FILIPJEV 



Leningrad, U.S.S.R., Seessel Research Fellc 

 Yale University 1928-29 



(Publication 3216) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



MARCH 20, 1934 



