1918] FITZPATRICK—RHIZINA 217 
by them as due to the “quadrivalent character’ of the chromo- 
somes in the fusion nucleus, which renders 3 mitoses necessary for 
the return to the univalent condition. When fewer than 8 spores 
are formed, the supernumerary nuclei degenerate (HARPER 41 
Phyllactinia Corylea) or two or more nuclei are incorporated in 
one spore (WOLF 68 Podospora anserina). When many-spored asci 
are formed, additional vegetative nuclear divisions take place 
following the triple division. 
In Eremascus fertilis (STOPPEL 60, GUILLIERMOND 36) the triple 
division occurs, but, as ATKINSON (1) has pointed out, there is here 
certainly only a single fusion, the antheridium and ascogonium 
being uninucleate and the fertilized ascogonium functioning as the 
ascus after fusion has occurred. Also in Dipodascus albidus 
(Juet 47) and Endomyces Magnusii (GUILLIERMOND 36) essentially 
_the same process takes place; a single nuclear fusion precedes 
spore formation, and the fertilized ascogonium functions directly 
as the ascus. In Endomyces Magnusii, moreover, according to 
GUILLIERMOND, only two divisions occur in the ascus and 4 
uninucleate spores are formed. 
The triple division in the ascus resembles very closely the process 
in the Basidiomycetes by which the basidium in some species (FRIES 
33 Nidularia pisiformis, LEVINE 49 Boletus spp., Strobilomyces 
strobilaceus) produces as the result of 3 successive nuclear divisions 
8 nuclei, which appear in 4 binucleate spores. Since in these cases 
the 3 divisions follow one another rapidly and a rest period then 
ensues, the resemblance to the process in the Ascomycetes is marked. 
Levine describes the third division as taking place always in the 
spore, and states that in Boletus albellus a fourth division occurs, 
the resulting 4 spores being tetranucleate. Fries states that in 
Nidularia pisiformis uninucleate spores are never found, and says 
that immediately upon the entrance of the nucleus completely 
into the spore a spindle is seen forming. He believes that the 
nucleus while migrating through the canal of the sterigma is already 
in the prophase of division. When it reaches the spore the equa- 
torial plate is formed at once. Marre (51) in Clavaria rugosa and 
Cantharellus cinereus figures the third division as taking place in 
_ the basidium itself. 
