NO. 16 MANTER : DISTRIBUTION OF DIGENETIC TREMATODES 541 



C. Endemic Galapagos species with nearest related species occurring in Japanese 

 waters 



1. Paramonorcheides 



bi'vitellosum P. azvataii Japan 



P. sirembonis 



2. Pseudocreadium spinosum Pseudocreadium species Japan 



3. Pseudolepidapedon balistis P. kobayashii Japan 



P. paralichthydis 



D. Endemic Galapagos species with nearest related species in the northern 

 American Pacific 



1. Opecoelina pacifica O.theragrae British Columbia 



(two other species in this genus occur at Tortugas, 

 Florida) 



2. Prosorhynchus rotundus P. scalpellus British Columbia 



E. Endemic Galapagos species with nearest related species not clearly evident 



1. Parvacreadium bifidus 



2. Podocotyle bre'viformis 



3. Podocotyle mecopera 



4. Prosorhynchus gonoderus 



A consideration of the above 21 species endemic to the Galapagos 

 Islands suggests closer relationship to the region of Tortugas, Florida 

 (West Indian and Gulf of Mexico regions), than to any other. 



The 18 additional species collected from the Galapagos Islands are 

 also known from other parts of the world. Ten of these are known from 

 Tortugas or the tropical American Atlantic; 6 were collected from the 

 Pacific coast of Mexico; 3 from the Pacific South American coast. Five 

 of the 18 species are known elsewhere only from the Tortugas region; 3 

 only from the Mexican Pacific; one only from Europe; one only from 

 the Pacific South American coast. A tabulation of these 18 species follows. 



