one male nucleus into the ooplasm. This nucleus joins the female, and 
each enlarges much before pronuclear union, which is completed in the 
ruins of the decadent coenocentrum. 
Simultaneous with the opening of the antheridial tube begins the con- 
struction of the oospore walls. These are completed much as in other 
species of Albugo, with the exception that there is a slight though very per- 
ceptible thickening of the oogonial wall itself. Such thickening is one of 
the chief features in the spore of Sclerospora, but is not known to occu in 
any other species of Albugo. ; 
Fic. 33. Fig. 2: 
Fic. 1.—Central globule and coenocentrum of A. [pomoeae-pa nd rs a 
second mitosis; one nucleus attached. 
oe : m. 
Fic. 2.—-Similar to fig. 1; nuclei not yet attached to the coenocent™ 
Subsequent to fertilization, which does not proceed with ate" 
slowness noted in some species, the fusion nucleus divides - ig 
increasing the number of nuclei before the assumption of the gi compe 
A minor point, worthy of mention as an indication fa t known 
sition, is a feature of the staining, conspicuous in this species — ? 
in any other Albugo. All of that portion of the a pe takes 
touches the periplasm, and often the whole antheridium ee 
the gentian-violet with great avidity and retains it longet pee cai 
structures. Antheridia and antheridial tubes are thus ose ith the t¥ 
ably conspicuous, and dozens are often seen in a single aren cue 
thirds objective-—F. L. Stevens, A. and M. College, West — 
$00 BOTANICAL GAZETTE focrone, 
