AKT. 13 TREMATODE PARASITES OF MARINE MAMMALS PRICE 25 



dorsoventrally ; seminal vesicle tubelike; undivided. Testes ellip- 

 tical, situated side by side in the posterior third of the body. Ovary 

 deeply lobed, situated immediately cephalad of testes and slightly to 

 one side of the median line; seminal receptacle moderately large, 

 dorsal to ovary. Vitellaria dorsal and extending from about halfway 

 between intestinal bifurcation and acetabulum to the level of the ends 

 of the ceca. Uterus long and strongly looped, occupying almost the 

 entire width of the body from the ovary to the genital pore ; vagina 

 short. Eggs oval, 23/i* to 25/a long by 14/x wide. 



Host. — Fhocaena phocoena {—P. communis). 



Location.. — Stomach (encysted in the mucosa of the pylorus). 



Distribution. — Europe. 



Family OPISTHORCHIIDAE Braun, 1901 



Family diagnosis. — Medium-sized to small forms; body elongate, 

 flat, thin, transparent, with weak musculature. Suckers relatively 

 weakly develoiDcd. Intestinal ceca simple, extending to posterior 

 end of body. Excretory vesicle Y shaped with long stem and short 

 branches. Genital aperture median, immediately preacetabular ; no 

 genital sinus containing suckerlike structures or gonotyls. Cirrus 

 pouch and cirrus absent; seminal vesicle coiled. Testes in post- 

 equatorial region, situated more or less obliquely. Ovary pretes- 

 ticular; seminal receptacle voluminous; Laurer's canal present. 

 Vitellaria lateral of ceca, moderately developed, not reaching poste- 

 rior end of body. Uterus long, with numerous loops, usually confined 

 to intercecal space between ovary and acetabulum. Eggs small and 

 numerous. Parasites of bile ducts and gall bladder of mammals, 

 birds, fishes, and reptiles. 



Type genus. — Opisthorchis R. Blanchard, 1895. 



KEY TO SUBFAMILIES OF OPISTHORCHUDAB 



1. Vitellaria and uterus do not extend cephalad of acetabulum. 



Opisthorchiinae (p. 25). 

 Vitellaria and uterus extend cephalad of acetabulum Tletorchiinae (p. 30). 



Subfamily Opisthorchiinae Looss, 1899 



, Subfamily diagnosis. — Opisthorchiidae : Excretory pore terminal ; 

 stem of excretory vesicle long. Vitellaria do not extend anteriorly 

 beyond level of acetabulum. Uterine coils usually confined to inter- 

 cecal space and not extending anteriorly beyond acetabuhnn. 

 Type genus. — Opisthorchis R. Blanchard, 1895. 



