FECUNDATION AND FORMATION OF THE PRIMARY 
ENDOSPERM NUCLEUS IN CERTAIN LILIACEAE 
MILDRED NOTHNAGEL 
(WITH PLATES III-V) 
Introduction 
Between 1890 and 1902 many articles appeared on fecundation 
and double fertilization in the angiosperms. On the whole, the 
authors have dealt with the entrance of the male nuclei, their 
behavior within the embryo sac, their form, the union between the 
egg and male nucleus, and between the male and polar nuclei; 
but they have not investigated in detail the chromatin changes 
that occur from the time of contact of these nuclei to the completion 
of the first division. 
In 1891 GuiGNArRD (6) described the entrance of the so-called 
antherozoids into the sac, each accompanied by its centrosomes. 
One male nucleus became applied to the egg nucleus, each of whi 
took on the resting condition and remained distinct for some time. 
While in this state the male nucleus enlarged and both the egg and 
the sperm nucleus flattened at the surface of contact, but with a 
distinct line of demarcation remaining between them for some 
time. Even after the nuclear membranes had disappeared, the 
contour of the two was traceable at the periphery. Later he dis- 
tinguished, on opposite sides of the nuclear cavity, two groups of 
chromatin in the spirem stage. No drawings were made to show 
this. When the nuclear plate was formed, he asserted that one- 
half of the chromosomes were contributed by the egg and one-half 
by the sperm. 
The process of fertilization in Lilium Martagon and L. candidum 
was described by Morttier (13) in 1898. In L. Martagon there 
was no complete fusion of egg and S-shaped sperm, the lack of which 
resulted in a failure to mature seeds. In the region of the two polar 
nuclei, which had not fused and which began disintegrating 96 hours 
after pollination, a nucleus, similar to the nucleus which united with 
143] [Botanical Gazette, vol. 66 
