TAPE WORMS 



253 



to the body is gained, it is known that the larval forms make their way to the liver 

 where they develop. Arriving at maturity, the males and females become united 

 and proceed to the terminal branches of the portal vein, where the irritating eggs, 

 given off by the female, give rise to the symptoms. 



Ova or the Parasitic Worms or Man 

 TREMATODA 



N TO SCALE X ICOO 



Heterophyes 

 heterophyes 



(after Loo*S.IQO,'5) ,y 



Di 

 coe 



l&ncetxtum 



Opisthorchis 

 felineus^ne 



Clqnorcliis Clonorchis 

 sihensis endemicus 



(Nodi:i.-il fiui:. LOOM.IW) 



Fasciola Fasciolopsis 



heptxtica buskii (*^^ 



{n.f\crtoos.l905) 



FIG. 66. Trematode ova. 



CESTODE OR TAPE-WORM INFECTIONS. 



The cestodes and trematodes constitute the two great divisions of 

 the flat worms. Anatomically, a tape-worm may be considered as a 

 series of individual flukes united in one ribbon-like colony. The 

 cestode segments, or proglottides are covered by an elastic cuticle and 

 in their interior usually contain striated elliptical bodies composed of 

 calcium carbonate about 5 to 25/1 according to the species in which they 

 are found. 



These calcareous bodies are characteristic of cestode tissue. They have been 

 mistaken for coccidia. There is no mouth or alimentary canal in tape-worms, the 

 segments absorbing their nourishment through the general surface. 



