153 
WHAT IS ^SCHISTOSOMUM MANSONF 
Sam BON 1907? 
uv 
Dr. a. LOOSS, 
VKOKKSSOR OK I'ARASITOI-OfJV, SCHDOI. OK MKOlCINE. CAIRO 
{Received for pnblicniion 21 yfarcli, 1908) 
About a year ago Dr. SamboX. of the London School of Tropical 
Medicine, startled the scientific world interested in human para¬ 
sitology by the creation of a new species of blood fluke, Schistosotmim 
mansoni, which he stated had hitherto been confounded with Sch. 
hematobium (1907a, p. ii;)- A suggestion to this effect had been 
made as far back as igo^ by Sir PATRICK MaNSON. SamboNs 
new species was thus readily adopted by ManSON in the new edition 
of his 'Tropical Diseases’ (1907, p. 660). From the West Indies 
there had come information which seemed to corroborate Dr. 
Sambon’s views (Holcomb, 1907). Later, the author gave a some¬ 
what fuller account of the new species (1907b, p. 303), and quite 
recently, he mentioned its existence as a fact in a paper On the 
Part played by Metazoan Parasites in Tropical Pathology,’ read 
before the Society of Tropical Medicine and Hygiene, London (1908, 
p. 29f). In this paper and in the ensuing discussion repeated allusion 
was made to the views hitherto held with regard to Bilharzia and 
Bilharziosis by the workers in Fgypt in general, and particularly by 
myself. It was hinted that we had not recognised the differences 
between two easily distinguishable species. If Dr. SambON s view 
were correct, all of us who have devoted attention to the subject, 
would have indeed been wandering in the dark since the time of 
Bilhaez himself, fifty-seven years ago. Since such a charge has 
practically been made I feel it necessary to take up the defence. 
1 may as well at once say that when in I.ondon two years ago I 
dropped some well-meant hints of warning to be cautious, whether 
to Sir Patrick MaNSON or to Dr. SamboN I do not remember. I 
am sorry that these hints have not been heeded, for if so the present 
disagreeable discussion might not have become necessary. 
