VOLUME XXXII NUMBER 2 
BOTANICAL (,AZEFTE 
AUGUST, roor 
GAMETOGENESIS AND FERTILIZATION IN ALBUGO. 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY. 
X XIX. 
FRANK LINCOLN STEVENS. 
(WITH PLATES I-IV) 
BEForE the publication of my paper (1899) describing the 
fertilization of Albugo Buti, the mature oosphere in the Phycomy- 
cetes was generally conceded to be a uninucleate structure. The 
question of homologies in the group did not then seem difficult. 
A. Bliti, however, presented a unique condition, in that about one 
hundred antheridial nuclei fuse in pairs with an equal number 
of egg nuclei. This condition seemed remarkable and inexpli- 
cable, inasmuch as Wager (1896) had studied the fertilization in 
A. candida, and had described a fusion of single male and female 
nuclei in a uninucleate oosphere. Such divergence in the same 
genus led to some speculation. Davis (1900) reexamined 4. 
candida and fully confirmed Wager’s account, as indeed Berlese 
(1898) had already done. It is well established, therefore, that 
there is a simple fusion in A. candida, and my own account 
(1899) stands for a multiple fusion in A. Buti, Interest also 
attaches to this genus on account of the presence of a coeno- 
centrum, a structure of prominence, but of hitherto unknown 
function, 
The study of A. Portulacae and A. Tragopogonis was under- 
taken in the hope that these species might help to explain the 
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