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the A scocarp in Monascus . 
In the cases of Monascus , Pyronema , and Dipodascus super- 
numerary gametes occur in the female organ, corresponding 
to the periplasm of the Peronosporaceae. In Sphaerotheca 
only one gamete seems to be produced in each organ ; but in 
this case the supernumerary gametes may be considered to 
have disappeared during the course of evolution, since peri- 
plasm is not needed to produce a wall for an oospore, which 
function it assumes in the Peronosporaceae, affording perhaps 
a reason for its presence in that group when only one gamete 
of the female organ is functional. 
In Pyronema and probably also Monascus , the development 
and behaviour of the gametes is like those in Albugo Bliti. 
The gametes in both organs are produced by nuclear division 
occurring shortly before fertilization. The female gametes 
aggregate into a ring or dense mass, from which the functional 
gametes separate. 
The behaviour after fertilization is the first important point 
of difference. Leaving out of the question the definite oospore 
stage of the Oomycetes, we find that the fertilized gamete or 
gametes in Albugo produce directly by division numerous 
spores. Dipodascus and Eremascus behave similarly. In 
Phytophthora omnivor a and most Ascomycetes, hyphae are 
produced from the fertilized cell which bear zoosporangia or 
asci. In many Oomycetes a mycelium is produced which bears 
fresh sexual organs. Thus in the Ascomycetes there is inter- 
calated a definite phase in the life-history, which may be 
regarded as a sporophyte generation between the gameto- 
phyte generations. In the Oomycetes certain members show 
signs of such a phase, but it is by no means general. Seeing 
that Albugo Bliti still possesses the most primitive form of 
fertilization, and, in addition, presents an example of an inter- 
calated sporophyte generation, the possession of two genera- 
tions by the ancestral Oomycetes ought perhaps to be assumed; 
and those members of that group which do not possess both 
ought accordingly to be regarded as having lost the sporophyte 
phase. The question oPrelationship thus turns on the homo- 
logy of the ascus with the zoosporangium. At present very 
