Embryo of Pseudolarix . 643 
come in contact in the middle region where they are widest. Even there 
the egg-cells never come into direct contact as in the Cupressineae and 
some of the Taxodineae, but they are always separated by one or two 
layers of jacket cells (Fig. 23). Each archegonium has its own archegonial 
chamber, and this more or less funnel-shaped depression above the neck 
is not so deep as that in Pinus (Ferguson ’ 04 ) and Tsuga (Murrill ’ 00 ) 
(Figs, 22, 25, 30). 
As the central cell of the archegonium reaches its full size, the nucleus 
prepares for division. Figs. 18 and 19 show the early prophase of the 
division, and we can see that the chromatic contents of the nucleus 
accumulate near the centre of the cavity in a condition suggesting the 
synapsis of the reduction division, as has already been observed in various 
other Abietineae (Murrill ’00, Miyake ’ 03 #, ’ 03 / 5 ). The first indication of 
the spindle formation is the appearance of a fibrous cytoplasmic cap at the 
lower side of the nucleus (Fig. 19). The process of the division does not 
seem to differ from that of other Abietineae. Fig. 20 shows the metaphase 
of the division ; the spindle is more or less pointed at the lower end and 
somewhat blunt on the upper side, as has often been observed in Pinus 
(Ferguson ’ 04 ) and Picea (Miyake ’ 03 ). 
The result of the division is the formation of the ventral canal-cell. 
The cell shows, however, signs of disintegration as soon as it is formed 
(Fig. 21). In the mature archegonium ready for fertilization, the ventral 
canal-cell usually appears as a deeply-staining lenticular or crescent-shaped 
cap over the top of the egg (Figs. 22, 24). 
The egg nucleus begins to enlarge soon after its formation, and moves 
down towards the centre of the egg. The mature egg nucleus situated 
near the centre of the archegonium is more or less spherical or elliptical 
and usually contains a nucleolus (Fig. 22). It has often been observed 
that the chromatic substance arranged in more or less irregular reticulum 
does not fill up the entire nuclear cavity, but is somewhat contracted on 
one side (Figs. 22, 24). This condition has been quite frequently found in 
apparently well-fixed eggs, but we have not been able to determine whether 
this is a normal structure or an artifact caused by reagents. 
After the division of the central cell, the number and size of the 
vacuoles in the cytoplasm gradually decrease, and in the mature egg 
there are usually found a few smaller vacuoles. The number of so-called 
proteid vacuoles seem to be not so numerous as in some other Abietineae 
(Figs. 17-22). 
In the mature archegonium previous to fertilization we have sometimes 
found an extra nucleus at the upper part of the egg (Fig. 24, x). A similar 
nucleus has been observed in the mature archegonium of Tsuga (Murrill ’00) 
and Abies (Miyake ’03 b). Murrill calls such a nucleus in Tsuga the nuclear 
vacuole. The origin and fate of the nucleus have not been followed. 
