Traiisi)iLs,siuii 5 



frequent among the French troops during the Napoleonic Invasion 



of Egypt, 1799-1801. It was not until 1851, how- 



DiscovEKv. ever, that the cause was recognized. In that year. 



Dr. Th. Bilharz, Assistant Professor at the Medical 



School in Cairo, wrote several letters to von Siebold announcing the 



discovery of a bi-sexual distome, which he named Distoma hmmato- 



bium, and successfully establishing a definite relationship between 



this trematode worm and the symptoms of dysentery and hsema- 



turia resulting from the corresponding lesions of the intestine and 



bladder. These letters were published by von Siebold in the 



Zeitschr. f. tvissenschaft. Zool. in the form of three articles 



during 1852 and 1853 [25], [26], [27]. 



The disease occurs in most parts of Africa, in 

 DisTOiBUTmN' '^^^ outlying islands of Cyprus, Madagascar, Mauri- 

 tius and Keunion ; in Mesopotamia, West Indies, 

 Porto Kico and Martinique especially, and in South America. 

 Cases have occurred sporadically also in India, Australia, and 

 England. The accompanying map gives the regions from which 

 cases have actually been reported, with reference numbers to the 

 papers in the Bibliography. 



In 1858 Weinland [515] created a special genus 

 Schistosoma, for the Distoimim hcetnatobiiim. In the 

 following year Cobbold [92] discovered a similar 

 parasite in the mesenteric veins of the sooty mangaby, Cercocehus 

 fiilginosus. For this he used the new generic and specific terms, 

 Bilharz ia magna. Later, Cobbold accepted Leuckart's view that 

 this species was identical with that described by Bilharz. 



In 1864 Harley [214] showed that the endemic hsematuria, 

 common in certain parts of the Cape of Good Hope and Natal was 

 due also to a species of Bilharzia, which he named B. capensis. 

 Writing in 1871, Harley [216] confessed, "I have never had much 

 doubt of the identity of the North and South African parasite, still, 

 I can only deal with facts, and my position with regard to the 

 question is pretty much the same as it was seven years ago. . . ." 

 "Both Bilharz and Griesinger describe and figure two forms of egg, 

 the one with a terminal and the other with a lateral spine. In all 

 my own cases I can say positively that only one form of egg has 

 existed,- viz., that with a terminal spine. I have never seen any 

 egg with even a tendency to the formation of a side spine." This 

 differentiation of species was strongly opposed by Cobbold. 



It would thus appear that the name B. hcematohia was primarily 

 associated by Bilharz with the parasites from the mesenteric veins 



