52 LIVER FLUKES 



dextro-laterally; genital pore opens into a genital sinus which 

 opens into a pit in front of the ventral sucker; the openings 

 of the genital sinus and of the ventral sucker are furnished 

 with complex muscular apparatus; found usually in upper 

 or middle portion of jejunum, rarely in caecum; cercaria 

 develops in redia in fresh water snail, Melania libertina; 

 encysted stage in muscles of fish, especially trout, Pleco- 

 glossus altivelus; man infected by eating uncooked fish con- 

 taining larvae; may cause chronic intestinal catarrh and 

 frequently destroys intestinal glands ; found in Japan, Korea, 

 Formosa and China in man, dog and cat. 



D. Liver Flukes 



The large sheep liver fluke, Fasciola hepatica, a closely 

 related species F. gigantica and the lancet fluke of sheep, 

 Dicrocoelium dendriticum have been reported as incidental 

 parasites of man. All the other human liver flukes, belong 

 to the family Opisthorchiidae, the representatives of which 

 are common in fish eating mammals. The only species of 

 medical importance are Opisthorchis felineus, Clonorchis 

 sinensis and C. endemicus. Some authors consider that the 

 last two forms represent but one species. In this outline 

 they will be considered, as separate species. Opisthorchis 

 viverrini, a common parasite of the Indian civet cat, has 

 been reported incidentally in man from Chiengmai, Siam. 

 Another species, Amphimerus noverca, has been found once 

 in man in Calcutta, India. 



1. Genus Clonorchis. Medium 'sized flukes; anterior 

 extremity somewhat pointed; body thin and transparent; 

 cuticula smooth; suckers small and weak, acetabulum being 

 smaller than oral sucker; testes situated one behind the other 

 at posterior end and very much branched; ovary and seminal 

 receptacle small, median, just in front of testes; coils of 

 uterus fill space between ovary, and acetabulum; habitat in 

 bile ducts of man, cat, dog, etc. 



