NOTES. 
SEXUAL SPORE-FORMATION AMONG THE SACCHARO- 
MYCETES 1 . — In a paper read before the Royal Society on June 6 
of this year the author has described a Yeast-form, the vegetative 
propagation of which takes place by budding in a manner exactly 
similar to that of Saccharomyces cerevisiae (Hans.) and other budding 
Yeasts, but which is distinguished from them by a curious process 
of spore-formation. The usual process among the Saccharomycetes 
is apparently a very simple one, the spores being formed under 
appropriate conditions in any cell by the division of its contents 
into a number of bodies, each of which develops into a spore. In 
this particular case, however, spore-formation is preceded by a kind 
of conjugation between two cells. Considering the case of any pair 
of cells which are about to take part in the process, the first stage 
consists in the development by each cell of a small protuberance. 
These protuberances are developed from neighbouring parts of the 
two cells, and grow towards each other, evidently under the influence 
of some stimulus acting between them. Growth continues until their 
tips are in contact, and then a solution of the walls at that point 
occurs, so that a continuous canal of communication is opened 
between the cells through the bridge or neck formed by the junction 
and fusion of the protuberances. Spore-formation then takes place, 
usually in each of the cells, although in some cases spores appear 
in one of the cells only, the contents of the other disappearing and 
leaving merely an empty sac. The spores make their appearance 
in a manner similar to that occurring in the other Saccharomycetes. 
No cases have been observed in which spore-formation was not 
preceded by conjugation. The behaviour of the nuclei during the 
1 Read before the Botanical Section of the British Association, at the Glasgow 
Meeting, September, 1901. 
[Annals of Botany, Vol. XV. No. LX. December, 1901.] 
