Reproduction of Cyst opus Candidus, Ldv. 311 
converted into fine granules distributed through the nuclear 
cavity, and finally in the mature gonidia the nuclei appear to 
be simply more or less homogeneous masses of iron-holding 
substance, while the cytoplasm does not contain a trace of 
the metal. 
In 1895 Istvanffi observed the multinucleate character of 
the vegetative hyphae in Cystopus Portidacae , Peronospora 
Ficariae , P. Chlorae , Phytophthora infestans , &c., and also 
pointed out that the conidia contain several nuclei. 
He investigated also the nuclei of the sexual organs in 
Cystopus PorUdacae. The material was hardened in alcohol, 
by which the fatty matters were dissolved out. 
The protoplasm, as it passes into the swollen end of a thread 
to form the oogonium, possesses a peculiar structure. It 
streams into the oogonium from the hyphae, and exhibits at 
the base of the oogonium a radiating structure which gradually 
passes over into a network. In the meshes of the network 
the nuclei are found ; only occasionally are nuclei to be found 
in the streaming portion. The oospore is formed out of the 
network of protoplasm, and appears as a large spherical body 
inside the oogonium ; its contents are formed of a quite dense 
protoplasm, and the network structure is no longer visible. 
The space between the oosphere and the wall of the oogonium 
contains epiplasm, which forms the brown, net-like thickening 
of the oosphere. The formation of the oosphere seems to 
take place only after fertilization, for the antheridium is 
already attached to the oogonium in the early stage, when 
its protoplasm still shows the reticulate structure. It contains 
many nuclei, and empties itself before the oosphere is rendered 
visible. It is probable that fertilization takes place by the 
fusion of the male and female nuclei. 
No reference is made to the separation of the nuclei in the 
formation of the oosphere, as to whether one or several nuclei 
remain in the oosphere, but in his explanation of Fig. 25 — an 
oogonium with oosphere in a young stage — he states that 
£ a part of the nuclei remain in the epiplasm,’ and figures also 
a large number of nuclei in the oosphere. 
Y 
