162 ENTOZOA FOUND IN MAN. 



This accident usually brings on a favourable 

 termination of the affection. 



Hydatids situated in the abdominal viscera some- 

 times open spontaneously through the parietes of the 

 abdomen ; the vesicles and the matter contained in 

 the cyst are discharged through the external aperture, 

 and complete recovery may result. In other cases 

 the fistula closes and is subsequently reopened, or the 

 tumour establishes a new communication with the 

 iQtestines. 



Chapter XXII. 

 HYDATIDS SITUATED IN THE TRUE PELVIS. 



Although the yielding nature of the parietes of the 

 abdomen, and the ready displacement of the viscera 

 contained within it, allow hydatids to grow to a large 

 size without the production of any complications, the 

 same is not the case when hydatids are developed in 

 the true pelvis ; the resisting character of its walls, 

 which prevent the displacement of the viscera, gives 

 rise to compression of the pelvic organs, and, as soon 

 as the tumour has acquired a moderate size, to very 

 serious affections. 



The hydatids in the pelvic cavity are usually 

 developed in the areolar tissue which invests the 

 various viscera. In the male they have no other 

 primitive seat ; but in the female a cyst which has 

 been developed in the ovary may extend into the 



