HEiLMINTH PARASITES OF BIRDS — DENTON AND BYRD 195 



Travassos (1922) described under the name Platynosomum mar- 

 quesi a dicrocoeliid from the gall bladder of the same South American 

 tanager, Thrcuupis pahnarwn. Subsequently, Travassos (1944, p. 

 159) recorded this species from several other South American birds 

 and declared his species to be synonymous with D. delectans Braun. 

 Travassos transferred the species to his newly created genus Zonor- 

 chis. If Travassos (1944) is justified in considering the material in- 

 cluded in his species marquesi to be synonymous with delectans Braun 

 (and we agree with Travassos' decision), the disappearance of the 

 discrepancies between fetiolatvmi Railliet and delectans Braun as 

 pointed out by Braun ( 1901, 1902) becomes apparent. It is suggested, 

 therefore, that the material now grouped under the name Zonorchis 

 delectans (Braun, 1901) Travassos, 1944, be considered a direct 

 synonym of Lyperosomum {= Dicrocoelium) petiolatum (Railliet, 

 1900) and that the species be assigned to the genus Zonorchis^ as 

 Zonorchis petiolatum (Railliet, 1900), new combination. 



The material in our collection is in perfect agreement with the 

 present concept of the species Zonorchis petiolatum, {= Z. delectans 

 of Travassos). From the material originally described by Railliet 

 (Z>. petiolatum) our material differs in having a smaller body, a 

 smaller sucker ratio, and smaller ova. From D. petiolatum as de- 

 scribed by Braun our material differs only in having a slightly smaller 

 body. On the other hand, our material conforms very closely with 

 Zonorchis delectans ( = Platynosomum marqu^esi) of Travassos with 

 the possible exception that the cirrus pouch in our material is slightly 

 smaller. 



DISTRIBUTION AND TAXONOMIC CONSIDERATIONS 



In a recent monograph, Travassos (1944) recognized 25 genera and 

 subgenera with approximately 136 species as comprising the subfamily 

 Dicrocoeliinae Looss, 1899, family Dicrocoeliidae Odhner, 1910. 

 About 84 species belonging to 16 genera and subgenera are recorded 

 from avian hosts throughout the world. The present paper reports 

 the presence of 9 genera and 22 species of dicrocoeliids from North 

 American birds. Three of these species, Athesmia wehri Mcintosh, 

 1937, from the prairie sharp-tailed grouse, Pedioecetes phasianellus 

 ca?npestris, in Montana, Concinnum (= Eurytrema) ludovicianae 

 (Petri, 1942) from the rose-breasted grosbeak, Hedymeles ludovici- 

 anus, in Nebraska, and Platynosomum (= Dicrocoelium) illiciens 

 (Braun, 1901) from the broad-winged hawk, Buteo platypterus, in 

 Ohio and Wisconsin, have not been studied by us. Of the remaining 

 19 species of dicrocoeliids from North American bird hosts 10 are 

 described as new. The hosts, geographic distribution, and authority 



