gto] BROWN—ASCOCARP OF LEOTIA 449 
This same method of multiplication of asci occurs in Geoglos- 
sum sp. (figs. 32-38). The two nuclei in the tip divide to four 
(fig. 32) and walls come in between the nuclei of each pair of sisters 
(fig. 33). The antepenultimate cell may then form an ascus 
(figs. 37, 38) or another hook (figs. 35, 36). The ultimate cell 
usually fuses wlth the stalk (figs. 34, 35). The nucleus of the 
ultimate cell may then migrate into the antepenultimate (fig. 35), 
but usually the nucleus of the antepenultimate cell migrates into 
the ultimate (fig. 34), which then grows out (fig. 36) to form a 
hook (figs. 37, 38) or an ascus. 
The phenomena connected with the formation of the asci as 
just described in Leotia and Geoglossum have been observed by 
the writer in Lachnea scutellata, as reported before the Botanical 
Society of America at the 1909 meeting (6). In a paper read at 
the same time before Section G of the A.A.A.S., McCuBBIN (21) 
described the penultimate cell of the ascogenous hyphae of Helvella 
elastica as forming either an ascus or a hook. The ultimate cell 
frequently fuses with the antepenultimate, after which the nucleus 
of the antepenultimate migrates into the ultimate. The two 
nuclei then migrate into a process which grows out from the ulti- 
mate to form another hook. In Humaria rutilans Miss FRASER 
(12) has described the uninucleate ultimate cells of the ascogenous 
hook as growing out to form other asci. She says that where such 
' proliferation had taken place the tip was usually connected with 
the stalk, and in one case the nucleus of the tip was migrating 
into the stalk. She did not determine, however, whether or not 
the nucleus of the stalk took part in the formation of new asci. 
It seems probable, however, that she has observed something of 
the same phenomenon that has been described in Leotia. The 
writer (5) has described the ultimate cell of Pyronema confluens 
as growing out to form other asci. In such cases a nucleus could not 
be found in the stalk cell, and so it may be that it had migrated 
_ into the ultimate cell and had then taken part in the formation 
_ of the hook. The presence of these phenomena in such rather 
distantly related species as those mentioned above suggests that 
they may be of rather frequent occurrence. 
Remembering that the nuclei in the binucleate antepenulti- 
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