1904] DAVIS—SEXUAL ORGANS IN PLANTS 255 
the case under similar conditions in Albugo Bliti and Pyronema. It 
is probable that the conditions in Gymnoascus will be found to be 
generally present in what are usually called the lower groups of the 
Ascomycetes. It looks very much as though such genera as Eremas- 
cus, Eurotium, Ceratostoma, Sordaria, and Ascobolus will be found 
to present sexual organs essentially similar to those of Gymnoascus. 
Their general agreement with the sexual processes of the Mucorales 
may have great significance in connection with the origin of the 
coenogamete and possible relation of the Mucorales and Ascomycetes 
to one another or to a common algal ancestry. 
Coenogametes of the second class are much better understood with 
respect to the details of protoplasmic structure and behavior than those 
of the first class. The development of the sexual organs and processes 
of fertilization are perhaps as well known in Albugo (STEVENS ’99, 
mt) and Pyronema (HARPER ’oo) as for any plant types. In Albugo 
Bliti and A. Portulacae the ooplasm contains numerous nuclei, and 
_@ equally large number is introduced into the egg from the male 
®venogamete, these sexual nuclei then fusing in pairs. Other species 
of Albugo (¢. g., A. Tragopogonis) show a lessening number of func- 
— and potential gamete nuclei in the egg, until forms are reached 
nA. candida and A. Lepigoni (RUHLAND ’03) whose eggs are nor- 
mally uninucleate. This series in the genus Albugo, so well described 
preci (or), is very interesting and we shall refer to it again. 
_ _nl€r genera of the Peronosporales have, so far as is known, 
unmnucleate eggs (Pythium, Peronospora, Sclerospora, and Plasmo- 
ge ‘a “a ronema there is developed a conjugating tube that takes 
hada — Coenogamete many of its nuclei. But a very large 
ous male ii : in the structure, and these fuse in pairs with numer- 
tube = a el that enter the female cell by way of the conjugating 
(03), cuts ss Coenogamete of Monascus, according to BARKER 
eee i sterile cell and thus disposes of some of its protoplasm. 
Barker's fo a of [keno (03) as to the systematic position of 
ai tly 7 with the life history after fertilization. There 
Organs. Rin. of BaRKER’s account of the structure of the sexual 
lor heliec. oUS% Not positively established, there are good reasons 
Pairs ag im the numerous gamete nuclei of Monascus fuse in 
80 Bliti, A. Portulacae, and Pyronema. 
. 
