640 Miyake and Yasui.—On the Gametophytes and 
during April to July. Part of the material was always fixed immediately 
after being received, and the remainder put in a moist chamber to be fixed 
later. The cone-bearing twigs were usually inserted into water under 
a bell-jar, and it was found that the cones showed normal development at 
least for several days. 
The fixing was done usually with Flemming’s chromosmo-acetic acid 
solution, chrom-acetic acid mixture being occasionally employed. After 
being embedded in paraffin in the usual way, the material was cut 5-10 // 
in thickness. For staining, Flemming’s triple combination or Heidenhain’s 
iron-alum haematoxylin were used. 
On account of the insufficiency of the material our results are not 
quite so complete as we had wished, but they show distinctly that the 
gametophytes and embryogeny of Pseudolarix closely follow the normal 
Abietinous type. 
The Male Gametophyte. 
The microspore seems to be quite mature at the end of March. In 
the male cones received early in April, the microspores were already fully 
formed, with well-developed wings, and many of them were found in the 
process of division. In fact, in cones of the same date we may find various 
stages of division which are described in the following paragraphs. 
The nucleus of the mature microspore soon divides to form the first 
prothallial cell (PI. XLVIII, Figs. 1-3). The first prothallial cell shows 
signs of disintegration soon after its formation and is at first found as 
a lenticular cell at the dorsal side of the microspore (Fig. 4). It, however, 
disorganizes quite rapidly and sooner or later becomes flattened against 
the spore wall (Figs. 5, 7). The second division follows immediately, and 
the second prothallial cell is organized, which soon shares the same fate 
as that of the first (Figs. 5, 7, 8-11). Fig. 6 shows a polar view of 
a- spindle of one of these divisions and the number of chromosomes is 
seen to be distinctly twelve. 
As the third division, resulting in the formation of the generative and 
tube cells, is completed, the two prothallial cells are seen as thin darkly 
staining bodies pressed against the dorsal wall of the pollen-grain (Fig. 8). 
The generative cell soon divides, and the so-called body and stalk cells 
are formed (Figs. 9-11). Now the pollen is ready for pollination. The 
number of cells in the mature pollen-grain of Pseudolarix is the same as 
in Larix (Strasburger ’ 72 , ’ 92 ) and Picea (Strasburger ’ 92 , Miyake ’ 03 #), 
while it differs from that of Pinus. In the latter the generative cell does 
not divide until some time after pollination (Strasburger ’ 92 , Ferguson ’ 04 ). 
Pollination seems to take place in Northern Italy about the middle 
or the latter part of April. It seems to occur somewhat later in Southern 
Germany ; for, judging from the male cones received from Baden-Baden 
