276 



THE ANIMAL PARASITES OF MAN 



V. 



u. 



Besides the bladder, the ureters and kidneys may in advanced cases 

 be involved. The prostate and vesiculae seminales are commonly 

 diseased. Eggs have been recorded in the semen. The urethra is 

 frequently attacked; the vagina in the female. 



Eggs also occur in the lymphatic glands of the gut. 



Geographical Distribution. East Africa : 

 Nile Valley, Red Sea Coast, Zanzibar, Portu- 

 guese East Africa, Delagoa Bay, Natal, Port 

 Elizabeth. 



South Africa : Cape Colony, Orange Free 

 State, Transvaal, Mauritius, Bourbon, Mada- 

 gascar. 



West Africa : Angola, Cameroons, Gold 

 Coast, Gambia, Senegal, Sierra Leone, Lagos, 

 Nigeria. 



North Africa : Tripoli, Tunis, Algeria, parts 

 of the Sahara. 



Central Africa : Sudan, various portions. 

 Uganda, Nyasaland. 



It occurs with varying frequency in these 

 regions. It is probably more widely spread 

 than this list implies, as undoubtedly many 

 cases are seen which are not recorded. 



Isolated cases have been recorded from 

 Arabia, India, 1 Greece, Cyprus. 



The means by which infection is brought 

 about are still uncertain ; we only know that 

 the miracidia (fig. 175) enclosed in the dis- 

 charged eggs do not hatch if the eggs remain 

 in the urine, but after cooling perish. As 

 soon, however, as the urine is diluted with 

 water the shell swells, generally bursting length- 

 ways, and releases the miracidinm from its 

 investing membrane, so that it can swim about 

 with the aid of its cilia. In its structure it 

 differs but little from the miracidium of Fasciola 

 hepatica, as, for instance, in the lack of eyes ; 

 the two large gland cells situated on either side of the intestinal 

 sac are also present in the miracidia of Fasciola hepatica. 



Sarcode Globules. This is a term applied to certain globules which at 

 times appear in the miracidium and are later ejected. Some authors 



1 In a case from Madras, recoided by Stephens and Christophers, the eggs were long and 

 spindle-shaped, quite unlike the eggs of Schistosoma hcematobium. 



V.d. 



V.sc. 



FIG. 1 74. Schistosoma 

 hamatobium, Bilh. : geni- 

 talia of the female. f.s., 

 ventral sucker; /., gut caeca ; 

 V.d. y vitelline duct; V.sc.> 

 vitellarium ; >., ovary ; Oe., 

 oesophagus ; Sh., shell 

 gland; /., uterus. Magni- 

 fied. (After Leuckart.) 



