XLV]
FASCIOLOPSIS BUSKI
847
The parasite
(Fig. 193) is the largest trematode inhabiting man. It measures 24 to 40 mm. or more (75 mm. according to Busk) in length by 12 to 14 mm. in breadth. In shape it is an elongated oval, rather narrower anteriorly than posteriorly, with flat ventral surface, slightly convex dorsal surface, and very thin margins. It has a smooth skin without spines. The oral sucker (0·5 mm. in diameter) is subterminal and placed on the ventral surface. The ventral sucker is larger (1·6 to 2 mm. in diameter) and placed close to the oral. It isFig. 193.—Fasciolopsis buski
(After Odhner.)
Pathogenesis and treatment.—This parasite inhabits the upper part of the small intestine. In two recorded instances (Cobbold) it was associated with attacks of recurring diarrhœa and other signs of intestinal irritation. The best treatment is thymol or eucalyptus oil, given as in ankylostomiasis.
Fasciolopsis rathouisi (Poirier, 1887)
Under the name of F. rathouisi a fluke was described by Poirier in 1887. The validity of this species has given rise to a good deal of discussion. Odhner, who has examined the type specimen, believes the so-called distinctive features are solely due to error in the interpretation of serial sections of F. buski.
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