NO. 14 MANTER : DIGENETIC TREMATODES OF FISHES 453 



Of 10 species of digeneti'c trematodes collected at Socorro or Clarion 

 Island (Revillagigedo Islands), Mexico, 6 occurred also in the Galapa- 

 gos Islands. Thus, the writer's preliminary observation (Manter, 1934a), 

 that the trematodes of these two localities were essentially different, is 

 not correct. However, species occurring in both localities may be much 

 more common in one, and fishes found in both localities may show a dif- 

 ferent infection percentage in one region as compared with the other. 



Thirteen species seem to be restricted to the American Atlantic and 

 American Pacific (i.e., they are endemic amphi-American). In each case 

 the hosts are different but related, and in each case the trematode genus 

 is a common, very widely distributed genus. 



The digenetic trematode fauna of the tropical American Pacific re- 

 veals a ver>' distinct similarity to the trematode fauna of the tropical 

 Atlantic. Otherwise, except for some similarity to that of the Japanese 

 waters, it is distinctly different from known trematode faunas in other 

 parts of the world. 



This aspect of the subject will be considered in a later paper. 





.^y 



