Organs and Fertilization in Picea excelsa. 359 
Formation of the Ventral Canal-Cell. 
As the central cell prepares for division the deeply staining 
substance, which is coarsely granular, accumulates near the 
centre of the nuclear cavity, in a condition suggesting 
synapsis, similar to that observed by Murrill (’00) in Tsuga . 
Soon there appears, along the lower side of the nucleus, 
a clear court which at first assumes a crescent shape in 
section, and later approaches to a conical form. Sooner 
or later delicate fibres make their appearance inside the 
court ; similar fibres also appear on the upper side of the 
nucleus. These fibres seem to represent the beginning of 
an extra-nuclear spindle. At the same time the upper and 
lower sides of the nucleus become more or less irregularly 
indented (PL XVII, Figs. 37, 38). The fibres seem to press 
the nuclear membrane from both sides, and finally to enter 
the nuclear cavity by the dissolving away of the membrane, 
which first takes place where the fibres are attached. Fig. 39 
shows a stage in which the nuclear membrane is still intact, 
except the side close to the fibres where it is beginning to 
disappear. Chromosomes about twelve in number are found 
inside the nuclear cavity. 
The spindle, when fully formed, is more or less pointed 
at the lower end and somewhat blunt on the upper side. 
It seems to lie wholly within the boundary of the original 
nucleus, so that one who had not seen the earlier stages of 
division might interpret the origin of the spindle as intra- 
nuclear (Figs. 40-43). The various stages of the division 
are shown in Figs. 37-48. The two daughter-nuclei are 
considerably different in size when they are formed, the 
nucleus of the egg being several times larger than that of 
the ventral canal-cell. The process of division is in the main 
similar to Pinus as described by Miss Ferguson (’01 b) ; the 
only noticeable difference is that no accumulation of chrom- 
atic substance has been observed in the early stage of division 
in Pinus. No trace of the dense fibrous mass beneath the 
