Notes. 
r4o 
spectively sixteen and eight chromosomes. I have myself arrived at 
this result for Lilium Mar/agon independently of Guignard, as also for 
the following plants : — 
Scilla non-scripta and other species 
Leucojum vernum 
Triticum vulgare 
Paeonia, several species . 
Aconitum Napellus . 
No. of chromosomes 
in Mother-cells in Archesporial 
of Pollen. 
cells. 
8 
l6 
12 
24 
8 
l6 
12 
24 
12 at least 
20 
probably 24 
Again, it was established by Guignard 1 and by the writer 2 simul- 
taneously that, in the Lilies and other plants where the cells which 
should correspond to the archesporium, to the mother-cells of the 
spores, and to the spores themselves of the higher Pteridophyta, are 
all represented by one and the same cell, the embryo-sac, the reduc- 
tion in the number of the chromosomes occurs in the nucleus of the 
young embryo-sac. Strasburger 3 had, however, already pointed out 
that in other plants, such as the Orchids and Allium , where the mode 
of development of the embryo-sac is more primitive, the reduction 
takes place in the nucleus of the mother-cell of the embryo-sac ; 
in a cell, that is, which is the morphological equivalent of a pollen- 
mother-cell. 
T urning now to the sexual reproductive cells of the Angiosperms, it 
has been shown by Guignard 4 and the writer 5 that the number of 
chromosomes in the nucleus of the oosphere of the Lilies is the same 
as that in the nucleus of the embryo-sac, that is twelve. Guignard also 
showed that each of the generative nuclei in the pollen-tubes of the 
Lilies contains only twelve chromosomes. Strasburger 6 arrived at 
similar results for Allium. 
From the foregoing facts it might fairly be concluded that, in the 
Angiosperms at least, the reproductive cells, whether sexual or asexual, 
contain only half as many chromosomes in their nuclei as do the 
1 Comptes Rendus, loc. cit. and Nouvelles Etudes. 
2 Beitrag zur Kenntniss der Entwicklung und Vereinigung der Geschlechtspro- 
duckte bei Lilium Martagon, Zurich, 1891. 
3 Ueber Kern und Zelltheilung, 1888. 
4 Nouvelles Etudes. 
5 loc. cit. 
6 loc. cit. 
