64 PROTESTS AND DISEASE 



contain bright globules. In this stage in Cornu's drawing 

 they look exactly like bodies from the cysts in a case of 

 cystic disease of the human urinary tract examined by 

 myself (1892) in the fresh unstained condition. These 

 bodies are termed " psorosperms " by some English patho- 

 logists, see Chapter X. 



Olpidiopsis saprolegniae 1 produces two kinds of sporangia, 

 smooth- walled and prickle-walled, Fig. 15, D and E. Fischer's 

 description of the zoospores differs from Cornu's, as shown 

 at B and E respectively. Zoospores from prickle- sporangia 

 are said to be double the size of those from the smooth. 

 Fischer described an alternation of generations, the zoospores 

 from the smooth sporanges growing into prickle- sporangia 

 and vice versa. In Fig. 15, E, is shown the mode of formation 

 of sporoducts by the prickle-generation. The contained 

 plasm of the duct-process like the rest of the parasite sub- 

 divides into zoospores. 



Cornu observed that the zoospores have a jerky move- 

 ment for a short time and that they disintegrate rapidly if 

 they do not succeed in finding a host. He also comments 

 on the resemblance of the plasm of Olpidium to that of the 

 Mycetozoa. 



Fischer described the protoplasmic motion that occurs 

 in the parasites as they break up into spores ; it would 

 appear to be similar to that I described in molluscum bodies 

 in 1895. Fischer states that countless spores are evacuated 



1 Differential features of Olpidium and Olpidiopsis are given on p. 61. 



