546 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



Some evidence is seen of relationship to the trematode fauna of Japa- 

 nese waters. 



Two possible explanations seem worthy of consideration, ( 1 ) the 

 interoceanic transfer of adult trematodes or their eggs by fish-eating 

 birds; (2) the influence of a former continuity between the two oceans. 

 The latter view is favored by the author. 



i 



