398 BOTANICAL GAZETTE [NOVEMBER 
In many cases the “leaf’’ was regenerated when only a part was removed, 
«but this differs from strict regeneration in that it is development of an organ 
from an already existent meristem. Studies upon other species of Strepto- 
carpus and upon the nearly related Monophyllaea, which normally produce 
true foliage leaves, showed many instances of this kind of “regeneration,” 
as well as numerous cases of regeneration in the wider sense of correlated 
development of other structures.—G. H. SHULL. 
THE FIRST account of nuclear conditions in the sexual organs of the 
Gymnoasceae is presented” by Miss E. Dale, who has studied especially Gym- 
noascus Reesit and G. candidus (Arachniotus candidus). Miss Dale estab- 
lishes beyond question the presence of a sexual process, supporting in the 
main the earliest account of this group by Baranetzky in 1872, and discredit- 
ing the later views of van Tieghem, Zukal, and Brefeld, who have denied the 
existence of sexuality, 
The sexual organs of Gymnoascus Reesii arise as two lateral branches on 
each side of aseptum. They grow out at right angles to the parent hypha 
and twist around each other, their free ends becoming swollen and finally 
cut off by a cross wall from the stalks below. These two cells generally fuse 
while there is yet little differentiation between them, but soon one develops a 
process that coils around the other, which remains straight and finally 
becomes spherical. The coiled cell divides by cross walls and from most of 
the segments one or two short thick branches arise as ascogenous hyphae 
whose ends develop into asci. 
Both sexual cells at the time of fusion contain large numbers of nuclei, 
and are therefore coenogametes, but when first formed there is only one 
nucleus in each cell. This nucleus probably divides to give the later multi- 
nucleate condition, but Miss Dale did not follow this process, nor did she 
determine with certainty whether the nuclei unite in pairs after the fusion of 
the coenogametes. The nuclei pass into the coiled prolongation, and thence 
into the ascogenous hyphae. The nuclear history during the development of 
the ascospores was not studied in detail. In Gymnoascus candidus the two 
coenogametes may not arise from the same hypha or simultaneously as in G. 
Reesti, but otherwise the two forms agree in all essentials. 
These studies add another type to the rapidly growing list of lowly Asco- 
mycetes whose sexual organs are coenogametes, and indicate that this condi- 
tion is likely to prove very general in the group. The possible bearing of this 
on the problems of the origin and relationships of the Ascomycetes is of great 
interest in connection with the conditions prevalent in the Mucorales, Sapro- 
legniales, and Peronosporales—a subject which the reviewer has recently 
considered in his paper on “Oogenesis in Saprolegnia.”*?—-B. M. DAVIS. 
* Date, ELIZABETH, Observations on Gymnoasceae. Ann. Botany 17:57 1-596. 
pls. 27, 28. 1903. 
* Bot. GAZ. 35 : 233. 1903. 
