$2 BOTANICAL GAZETTE [ AUGUST 
the second mitosis, while in A. But it precedes the preliminary 
massing of the cytoplasm. In A. Portulacae the oosphere some- 
times protrudes into this papilla, a phenomenon not occurring in 
A. Bliti, since its oosphere has not been differentiated when the 
papilla is formed. The condition presented in fig. 6 shows that 
sometimes the papilla becomes ruptured. This I cannot regard 
as normal, however, since only one of the hundreds of prepara- 
tions examined shows such a condition. 
The mode of formation of the antheridial tube is uncertain. 
In somewhat advanced stages it is found extending nearly to 
the center of the oosphere. It has a well-defined wall, and is 
firm and straight (fig. 8), differing from the swollen gelatinous 
tube of A. Tragopogonis and A. candida, but agreeing closely 
with that of A. Blin. 
In no case was the antheridial tube in a mature oogonium 
seen to contain less than fifteen nuclei, and in most cases there 
are probably 150 or more. I have seen the tubes in transverse, 
longitudinal, and oblique sections, and they were always multi- 
nucleate and extended into multinucleate oospheres (figs. 7-9). 
The male nuclei are oval as they lie in the end of the antheridial 
tube, and stain more darkly at the anterior end. Whether there 
is any constant numerical relation between the sperm nuclei and 
oospheric nuclei could not be determined with any accuracy, 
owing to the great number of sperm nuclei crowded into the 
antheridial tube. When fully developed, the antheridial tube 
opens as in A. Butt. There is first a softening of the wall, which 
is probably due to the presence of an enzyme, and it is finally. 
dissolved, allowing the nuclei to escape and pair with those of 
the oosphere (figs. ro, zz). Before fusion both male and female 
nuclei enlarge somewhat, although they maintain a typical rest- 
ing condition during fusion and regain their original size soon 
after. The result is an oospore containing between 100 and 200 
nuclei, which passes the winter without further change. 
A very few winter spores were seen with a relatively small 
number of nuclei, in one case as few as six, but this condition 
must be regarded as very exceptional. Such cases probably 
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