1899] THE COMPOUND OOSPHERE OF ALBUGO BLITI 173 
A stage of somewhat frequent occurrence is shown in fig. 87. 
Judging from the presence of the primitive wall, the character of 
the ooplasm, and the absence of the antheridial tube, it must 
follow the opening of the latter, and since the nuclei are not yet 
paired must precede the condition shown in fig. 88. There are 
two possible explanations for this condition, consisting as it does 
of an oospore containing several groups of nuclei, each cluster 
imbedded in a mass of denser cytoplasm. Perhaps these nuclei 
are gathering the cytoplasm about themselves, a phenomenon of 
rather frequent occurrence with sexual nuclei; or it may indicate 
the breaking up of the mass of nuclei and cytoplasm that was 
released from the antheridial tube. The latter explanation 
seems more probable. If it be true, a stage similar to that 
shown in fig. 88 would result through a further fragmentation of 
these nucleated masses of denser cytoplasm. 
The previous pages have dealt entirely with descriptions of 
the antheridial tube, the discharge of its multinucleate contents, 
and: the Subsequent fusion of sexual nuclei in pairs. For the 
a of completeness, and in view of the peculiarity of the con- 
ditions and the general, if not universal, belief in a simple pro- 
hs % fertilization, involving only two sexual nuclei, it seems 
desirable to discuss the possibility of such an occurrence taking 
~ in the oosphere, together with the events already described. 
eli fertilization predicates the existence of one jeutete 
ews ay . oosphere i one male nucleus in the antheridium ; 
ture and e alone, or if with others at least different a struc- 
ation the o Action from them. Subsequent to its final differenti- 
Stage “5a os Sidi contains less than 40 nuclei. Ata later 
but Neither - aera: and oosphere contain about 100 peter 
the others Seal single nucleus differing in appearance i 
le cosphere iso uninucleated oosphere exists it must be bel ore 
shows is fully differentiated. A glance over the drawings 
there ever — uninucleate stage is represented, nor was 
MOSt Dersiste slightest hint of such a condition found cn a 
nt search, involving hundreds of oogonia. That . 
(have existed and escaped observation seems very 
