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THE FLUKES 



FIG. 63. Life history of liver fluke, Fasciola hepatica; A, adult in liver of sheep; 

 B, freshly passed egg; C, egg with developed embryo, ready to hatch in water; D, 

 ciliated embryo in water, about to enter pulmonary chamber of snail (E) ; F, 

 sporocyst containing redise; G, redia containing daughter redise; H, redia of 2nd 

 generation containing cercarise; /, cercaria; J, same, having emerged from snail 

 into water; K, cercarise encysted on blade of grass; L, cercaria liberated from cyst 

 after ingestion by sheep; M, young fluke developing in liver of sheep. 



