296 ON SOME TREMATODE PARASITES OF AUSTRALIAN FROfiS, 



The anatomical description is followed by general remarks, and 

 a discussion of the relationships of the worm described. For 

 the new genera, descriptions with the more special characters 

 emphasised by italics have been given, as this procedure appears 

 to me to be more satisfactory than that of designating a genus by 

 merely naming its type-species. The worms here described 

 are :-- 



Order HETEROCOTYLEA Mont. 



Family Pol vstomid^e Taschbg. 



Subfamily PolystomJnse van Ben. 



Genus Polystomum. 



Species —6?t//iewse. 



Order M ALACOCOTYLE A Mont. 



Family Paramphistomid.e Fisch. 



Subfamily Cladorchinee Fiscli. 



Genus Diplodiscus Dies. 



Species — megalochrtis, microchrus. 



Family FASCiOLiDiE Rail. 



Subfamily Plagiorchinae fjUhe (Lepodermatinfe Looss). 



Genus DoLiCHOSACCUS, gen.nov. 



Species — trypherus, ischyrus, diamesus. 



Genus Brachysaccus, gen.nov. 



Species — anartius, symmetras. 



Subfamily Haplometrinfe Pratt. 



Genus Pneumonceces Looss. 



Species — australis. 



Family G o r r, o d e r i D ^ Looss. 



Subfamily Gorgoderinae Looss. 



Genus Gorgodera Loo.ss. 



Species — mistraliensis. 



Family B u a c h v c ce l i i D iE. 



Subfamily Brachycceliinae Looss. 



Genus Mesoccelium Odhn. 



Species — mfsembrinum, oligoon, megaloon. 



Subfamily Pieurogenitinae Looss. 



Genus Pleuhogenes Looss. 



Species — freycineti, solus. 



