INTESTINAL TREMATODES 51 



1. Fasciolopsis buskii. Large thick brown trematode; 

 length 24 mm. to 70 mm. breadth 5.5 mm. to 14 mm.; no 

 cephalic cone present; intestinal ceca unbranched; ovary 

 and testes greatly branched; acetabulum larger than oral 

 sucker, near anterior end; genital pore just in front of 

 acetabulum; cirrus sac very long, about one-fourth body 

 length; intestine of pig and man; life history and method of 

 entrance into man unknown; produces intestinal disturb- 

 ances; reported from India, Siam, China, Cochin China, 

 Assam, Sumatra; common in some regions in man and pig. 



Four other species of this genus, Fasciolopsis rathouisi, 

 goddardi, fulleborni and spinifera, have been reported from 

 man by various authors. They have been separated on 

 minor structural differences and the true number of distinct 

 species is still in doubt. 



2. Heterophyes heterophyes. Very small, pear-shaped; 

 length up to 2 mm. breadth 0.4 mm. to 1 mm.; body covered 

 with tiny serrate scales; acetabulum much larger than oral 

 sucker; genital pore just behind the acetabulum, to the side 

 and surrounded by a very characteristic annular muscular 

 elevation, provided with 75 to 80 branched chitinous hooks; 

 habitat small intestine; life history and method of entrance 

 into man unknown; pathogenicity probably nil; reported 

 in man from Egypt, Japan and China, from dogs and cats 

 in Egypt, Japan and Formosa. 



Another species of this genus, Heterophyes nocens has been 

 described in man from Japan. This form is smaller than 

 H. heterophyes and differs in structural details. The en- 

 cysted stage is found in fish, man being infected from eating 

 raw or imperfectly cooked fish. 



Si Metagonimus yokogawai. Very small form; length 1.5 

 mm. to 2.5 mm., width 0.4 mm. to 0.7 mm.; surface of body 

 covered with nail shaped spines, about 10/i in length; 

 acetabulum sac-like, placed deeply in the body and opening 



