P. Manson-Bahr and N. H. Fairley 35 
hatched from terminal spined ova, and has described the morphology of the 
cercariae so produced. 
Lutz (1917) and Iturbe (1917) have confirmed Leiper’s observations in 
Brazil and Venezuela respectively by tracing the development of Schistoso- 
mum mansoni in the local species of Planorbis ( P . olivaceus), and the former 
has succeeded in infesting rabbits and guinea-pigs under experimental con¬ 
ditions. 
It is only fair to state that after the Japanese discoveries were published, 
Looss, still mindful of his own failure and that of Sonsino to identify bilharzia 
cercariae amongst the numerous developmental forms found in snails in the 
endemic centres of Egypt, suspected that Schistosomum haematobium had a 
life history which materially differed from S. ja'ponicum. 
In estimating Leiper’s work on this subject one should not forget that 
was the prevalent view at the beginning of the war* and furthermore the real 
value of much of the Japanese work was lost to science at that time because 
the original articles were printed in Japanese journals in the native language 
and had not then been translated into either German or English. 
II. SCOPE OF THE PRESENT INVESTIGATION. 
The experimental data and observations on which this paper is based were 
collected after the departure of the Bilharzia Mission from Egypt at different 
periods, as far as military exigencies would permit, from 1916 onwards till 
the end of 1918. Through the generosity of the Australian Red Cross Society 
and of the Australian Military authorities, the cost of the experimental 
monkeys which were utilized was defrayed. 
During these years a large number of troops, Imperial, Colonial and Indian, 
were stationed in districts heavily infested with bilharziasis. Although timely 
warnings were given by Dr Leiper and his Commission, a considerable number 
of troops became infested. From the fact that isolated posts were maintained 
during 1916 and part of 1917 along the Sweet-water Canal, and large bodies 
of troops were stationed in the Fayoum in close proximity to various collec¬ 
tions of water it is not surprising that many men became victims of the disease. 
It is probable that we have been able to trace but a small percentage of 
the infections originally acquired in Egypt, as a large number of men who had 
been stationed in the endemic zones were moved to France during the years 
1916 and 1917 and probably only developed the symptoms of the disease at 
a later period. 
The earliest cases among the Australian troops were accompanied by py¬ 
rexia, urticaria and general toxaemia and thus escaped recognition at first 
sight. These were probably examples of a massive infection; in the later cases, 
especially the more chronic vesical infections, these generalized symptoms were 
not so common. 
The results of the present enquiry, which has entailed a considerable 
amount of work and the dissection of over 10,000 snails, has been to confirm 
