484- V. A. I'OTTS. 



(9) No iniiles luive been observed in this species, so that 

 they are either excessively rare or extinct. R. g-urneyi, 

 then, represents a much more complete and sufficient type 

 of hermaphroditism tliaii lias hitherto been recorded in the 

 free-living nematodes. 



(10) Self-fertili.sMtion has formed the exclusive means of 

 propagation thi'oughout twenty-five' generations of Diplo- 

 gaster mauj)asi without any deterioration in the character 

 of the stock. 



' Now forty-six. (See note on preceding page.) 



