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would assume wliat we have called above tlieir normal course. After 
due time terminal-spined ova would appear in the urine, wliile the 
lateral-spined eggs of the liver continue being voided by way of the 
rectum. I will not spin out lliis narrative any more. I tliink it will 
now be seen tliat in the way alluded to the clinical and pathological 
picture shown by the infection in any particular individual must 
depend upon the more or less favourable nature of the conditions of 
infection to which the individual has been exposed. A first infection 
with one or some male sporocysts would not lead to any consequence. 
A first infection with a female sporocyst would give a picture typical 
of ‘ Maxson’s Bilharziosis,’ i.e., an untouched bladder but lateral- 
spined eggs appearing for years in the faeces. In all countries where 
infection with ScJi. hcematobiiim is possible, a man once infected will, 
as a rule, be subject to the opportunity of re infection. The aspect 
the disease will then show must vary with the intervals at which the 
infection becomes repeated, and with the sex of the worms which are 
acquired. We may get pictures such as represented by the case of 
Letulle, where the external aspect still preserved the features of 
‘MaN'SON’s Bilharziosis/ but where, internally, the normal, terminal- 
spined eggs were found in company with the lateral-spined type. If, 
finally, a man once only in his life, and perhaps for a few hours only, 
happens to come under a peculiar combination of circumstances which 
favour a simultaneous entrance of a larger number of miricidia, even 
in a country where otherwise the conditions for infection are 
unfavourable, he will contract for perhaps three, perhaps six, perhaps 
more years ‘urinary Bilharziosis/ either pure, when he was not 
previously infected, or mixed with ‘ Manson’s Bilharziosis,’ when he 
was infected with this peculiar type before. I am personally perfectly 
sure that the four cases of urinary Bilharziosis quoted by HOLCOMB 
were contracted in loco after the fashion here described. 
On the whole, therefore, I do not, from my point of view, see any 
shaq) line of demarcation between the two types. They are simply 
the opposite ends of a continuous series of intermediary stages. 
I cannot quit this subject without drawing attention to another 
point which seems to me of great interest. We have seen that 
Letulle expressly states that in his case the bladder was entirely 
free from infection. I can only interpret this statement in the sense 
that no pathological changes were perceivable in the bladder, but I 
