FLAT WORMS AND THREADWORMS 



301 



Fig. 188. 



Oxyuris Vermicularis 



The male is on the left, the 



female on the right. 



(After Glaus.) 



17 



Fig. 189. 



Eggs of the More Important Worms Which Are 

 Parasitic to Man. 



As all are of the same magnification, a comparison of the rela- 

 tive sizes is possible. 



1, Fasciolopsis buskii; 2, Schistosoma mansoni; 3, Schistosoma 

 hacmatobium ; 4, Schistosoma japonicum; 5, Paraffonimus wester- 

 manii; 6, Clonorchis sinensis; 1, Metagonimus yokogawai; 8, Taenia 

 saginata; 9, Taenia solium; 10. Hymenolepsis nana; 11, Hymeno- 

 lepsis diminuta; 12, Diphyllobothrium latum (Dibothriocephalvs 

 latus) ; 13, Ascaris lumbricoides (egg without outer coating) ; 14, 

 Ascaris lumbricoides (abnormal egg) ; 15, Ascaris lumbricoides; 1C. 

 Trichuris trichiura; 17 and 18, Hookworm eggs; 19, Enterobius 

 vermicularis oxyuris vermicularis ; 20, Oxyuris incognita; 21, Tricho- 

 strongylus orientalis. (After Hegner and Cort's "Diagnosis of Pro- 

 tozoa and Worms Parasitic to Man." Bull. Johns Hopkins Uni- 

 versity school of Hygiene and Public Health.) 



derm of the body wall as a lining. There is no mesodermal lining sur- 

 rounding the intestines. Then, too, the excretory organs open directly 

 to the outside through the excretory pore, and the reproductive cells do 

 not originate from the epithelium of the coelom. Notwithstanding this 



