and Fertilization in Oenothera. 
285 
were observed lying in the egg-cells. The materials for these sections were 
partly fixed with Bonin’s fluid and partly with Benda’s fluid. 
1, 2, Text-fig. II, which were drawn from the preparations stained with 
iron-alum-haematoxylin, illustrate two cases in which these structures are 
found. In the first figure the egg apparatus is shown, in which the synergid 
darkly shaded is plumped 
by the attack of the pollen- 
tube, while the other is 
shrinking. Between those 
is situated the fertilized 
egg-cell, two synergids con¬ 
taining a small number of 
the structures in question, 
which are scattered between 
the cell-wall and the right- 
hand side of the nucleus. 
The second figure repre¬ 
sents a section of the 
oosphere showing two 
groups of those structures, 
each small body of which 
makes a pair and looks as 
if the couple has just been 
derived from a common source by division. Unfortunately, the specimens 
are not sufficient for a more detailed examination. * But judging from 
all the appearances these small bodies seem to be something like 
chondriosomes. 
Text-fig. II. 1. Hybrid l pycnella\ Egg apparatus 
showing chondriosome-like structures in a fertilized egg-cell. 
2. Oenothera nutans. Oosphere containing two lumps of 
chondriosome-like structures besides some starch grains. Both 
figures x 1,300. 
Doubling of Embryo Sac. 
Among the Angiosperms the occurrence of the excess embryo sac 
mother-cell is commonly known. Oenothera is not exceptional in this 
respect. Geerts ( 21 ) reported such a case in Oe. Lamarckiana\ and the 
same was also described by Tackholm (68) for Oe. biennis , in which two 
rows of the tetrads occurred lying side by side. Besides, he met with four or 
five definitive archesporial cells in the closely related genus Lopezia, and 
always several mother-cells in Godetia and in Clarkia ( 69 ). Text-fig. Ill, 1, 
shows two embryo sac mother-cells in synapsis lying one upon the other. 
Text-fig. Ill, 2, represents two rows of the tetrads, one set normally 
developing and the other showing a sign of disintegration. Several other 
cases have been studied, with a result that only one of the mother-cells or 
its derivatives is functional. 
Many cases have been reported where several primary embryo sac 
cells, derived from the different mother-cells, start forming the embryo 
