Schistosomum Mansoni and Schistosomatosis 
observed in Brazil 
by 
ADOLPHO LUTZ, M. D. 
(With Plates 37 — 43). 
a 
Biology and evolution of the trematodes 
belonging to the genus Schistosomum were 
but little known until a few years ago, but since 
1911 several papers were published which 
gave the solution of the most important pro- 
blems for four species. I report here the re- 
sults of my investigations, directed mainly to 
repeating and controlling the recent experi- 
ments in connection with the only species 
known in Brazil, yet alsoto determining the 
local species of the intermediary host and 
the conditions of infection in this country. In 
order to give more pratical value to my pa- 
per and to help the orientation of the rea- 
ders, I decided to recall briefly the most im- 
portant facts in connection with the parasitism 
of all the schistosoms and particularly the 
species Mansoni. Of litterary references I 
only give the most important and those in 
closer connection with my paper; for the rest 
I may refer the readers to the list given by 
LEIPER (1915) which is easily obtained and 
very extensive, containing 529 numbers. 
I shall first consider the historical and 
and geographical part of our knowledge con- 
cerning the genus Schistosomum and the dis- 
eases caused by the same. 
jo 
Schistosomatosis or Bilharziosis in 
Africa. 
The troubles caused by the African spe- 
cies of Schistosomum were known long be- 
fore their cause and existed in remote periods, 
as the examination of mummies has proved. 
Since the invasion of Napoleon until our 
time they were very common there. In this 
classical field of observation the parasites 
were discovered in 1851 by BILHARZ who 
called them Distoma haematobium, on account 
of their inhabiting the blood vessels. He was 
well fit for such studies and recogni- 
zed that this very peculiar trematode was spe- 
cially caracterized by separate and bimorphic 
sexes, a quite new and unexpected fact. The 
name Schistosoma WEINLAND, now gene- 
rally latizined (Schistosomum), seems to apply 
to the male whose body has a fissure, ope- 
ning a longitudinal furrow in which the fe- 
male is carried. Hence the name Gynaeco- 
phorus, given by DIESING in 1859, In the 
same year COBBOLD introduced, in honour 
of the discoverer, the name Bilharzia which, 
as well as the derived expressions Bilharzia- 
sis and Bilharziosis, was commonly employed. 
