SCHISTOSOMIASIS 



245 



Others believe that the life-cycle, like that given of a typical trema- 

 tode (p. 235), is necessary. 



The African natives believe that it gets along the urethra while they 

 are bathing, and tie twine around the penis to prevent the infection. 

 Bathing does seem to account for many infections and drinking 

 impure water for others. There is no evidence for direct contagion. 



PATHOLOGY. 



The irritation set up by the eggs causes a round-celled infiltration. 

 The epithelium proliferates, and flattened projections are formed which 



Ovum of Schistosoinum luemaiobhim. For comparison witli Schistosoinu»i japotnciiin and 

 Schistosomum tnansoni. This parasite has not yet been reported in China, and is probably 

 not found there. (By William Pepper, Philadelphia.) 



feel sandy to the touch ; these may go on to form vesicles and ulcers in 

 which eggs can be found. The eggs can escape without ulceration. 



The bladder wall is much thickened. 



The pelvis of the kidneys and the meatus urinarius may also be 

 affected. 



Turner has found the eggs in the lungs. 



P.M. 



The bladder mucosa is much thickened with bilharzial tissue, 

 covered with adherent mucus containing many eggs. 



Vesicles are most frequently found around the trigone, containing 

 a whitish fluid and eggs. Papillomata may be formed. 



