292 



General Biology 



Schistosoma Japonicum. 



<S , male, containing the female 

 the gynaecophorous groove, gng. 

 Rivas.) 



?, in 

 (After 



means uncommon in tropical countries such as Asia and Africa, and is 

 sometimes found in Europe and America. 



The mature worm lives in the branches of the portal veins so that 

 the eggs are easily distributed (with the blood) into the liver and other 

 organs of the body. The eggs, which are the true cause of the disease, 

 have a tendency to affect the urinary apparatus, causing a bloody urine 



to be discharged and also causing de- 

 structive and over-growth processes in 

 the bladder, urethra, and surrounding 

 parts. All these infected parts are 

 loaded with eggs so that abscesses and 

 fistulas form. Similar conditions may 

 take place in the rectum. Ten per cent 

 of. all patients in Cairo were found to 

 be infected, while seven and a half per 

 cent of all army recruits in Egypt 

 showed the eggs in their urine. 



Schistosomum Japonicum is the 



Japanese species. 



This blood-fluke is peculiar in that it has separate sexes, the male 



being carried about by the female in a gynaecophorous canal (Fig. 181). 



The eggs are oval and a terminal spine is found at one end. The 



eggs hatch in water, so they may be taken in with raw vegetables or 



even with drinking water. 



It is an interesting fact that animal parasites often cause no pain, 

 but are on that very account the more dangerous. The patient infected 

 pays no attention to his infection, and the disease grows constantly 

 worse because no remedial measures are taken. 



Schistosoma japonicum vel cattoi. This species is common in China, 

 Japan, and the Philippines. The disease produced by it is called 

 Katayama disease. The liver hardens and the spleen enlarges. There 

 is dysentery and loss of blood. The eggs are smaller than S. haemato- 

 bium, and the species do not have the terminal spine. 



In Formosa, Paragonimus Westermani (Fig. 182), (Asiatic lung' 

 fluke or bronchial fluke), is often found as a parasite infecting the lungs 

 of man. It is also found in the brain where it causes death from 

 pressure. 



The worm is from 8 to 16 mm. long and from 4 to 8 mm. broad, 

 and is pinkish or red in color. The disease it causes is often confused 

 with tuberculosis, although the microscope shows many eggs in the 

 sputum. The liver, brain, and eyelid are the points most commonly 

 affected. 



The common liver-fluke, Fasciola hepatica, though rare in the United 

 States, is common in Syria where men eat raw goat-livers. The disease 

 is called Halzoun. 



