SCHISTOSOMIASIS 



243 



Calcified eggs liave been found in mummies of the 20th dynasty 

 1 250-1000 B.C. 



THE PARASITE. 



S. haematobium, it is a bisexual trematode. 



MORPHOLOGY. 



The Male. — This is from 12 to 14 mm. long by i mm. broad. It is 

 thin and flat, the lateral margins may be turned inwards forming the 

 gyn^cophoric canal in which the female lies, thus giving to the male 

 a filiform appearance. 



The cuticle is bossed with short spines to enable it to cling to the 

 walls of the vessels and travel against the blood-stream. There is no 



Ovum of Schistosoma 

 hamalobium, Bilh.,with 

 miracidium, which has 

 turned its anterior end 

 towards the posterior 

 end of the egg. 275/1. 

 {After Looss. ) 



Ovum of Schisiosomum kcematobium, 

 with terminal spine. (Not found in 

 China.) The patient was in the African 

 mounted police. (By William Pepper, 

 Philadelphia.) 



pharynx, but the oesophagus is long with two c^eca which unite behind 

 the testes into a median trunk. 



The excretory pore is postero-dorsally situated. 



There are four to five testes. 



The Female. — This is 20 mm. long by 0-25 mm. thick. It is a 

 long, thin trematode with a smooth cuticle except about the sucker and 

 tail-end, where there are large spines. 



The alimentary canal is as in the male. 



The uterus ends in a genital pore just behind the ventral sucker. 



The eggs are large, o"i8 by o'o6 mm., oval, yellowish, with a thin 

 shell, slightly transparent, no lid, and a terminal spine at the posterior 

 end. 



