DIPYLIDIUM CANINUM 



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FIG. 219. Dipylidium caninum : central portion of a proglottis. C.p., cirrus 

 sac; V.s., vitellaria ; Ex.v., excretory vessels ; T., testicles lying in the meshes 

 of the uterine reticulum which laterally forms pouches ; O., ovary ; U., reticulum 

 of uterus ; V. t vagina and seminal receptacle (below ovary). Magnified. '_ (After 

 Neumann and Kailliet.) 



FIG. 220. Dipylidium caninum : development of embryo. I, solid hexacanth embryo ; 

 2, primitive lacuna (a) in the embryo ; 3, elongation of hinder part, rudiments of sucker and 

 rostellum appearing ; 4, " body " and " tail " distinct, (b) and (c] excretory system ; 5, fore-body 

 invaginates into hind-body, excretory bladder has a pore ; 6, tail has dropped off; scolex 

 growing up into secondary cavity formed by fore-body ; the primitive cavity has been absorbed 

 at stage 4. (After Benham, Grassi and Rovelli.) 



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