DEVELOPMENT OF PISTILLATE CONES. 1 
of the female cones throughout their existence, except at the time of 
pollination, are tightly closed, so that no dust can gain admission to 
the interior (figs. 2 and 6). When the cone is receptive and ready 
for pollination the basal scales of the cone separate from those aboye, 
leaving a crack about one-eighth to one-fourth of an inch wide between 
them. This crack extends around the entire base of the cone and 
apparently remains open at least a day or more, though the time has 
not been determined by actual observation. When the ovules are pol- 
linated, apparently the row of scales immediately above this move down- 
ward, closing the original crack and leaving a similar opening between 
them and the row of scales next above. This process evidently con- 
tinues in succession, following the spiral arrangement of the scales, 
until the top is reached and all of the ovules have been pollinated. 
Several days are evidently consumed in the process of pollination of 
a single cone. The scales evidently reverse in quite regular order, as 
the opening between them is never found here and there over the cone, 
but always in a continuous and quite regular crack running around 
the cone. A single scale does not remain open longer than others 
because its ovules have not been pollinated, as might be supposed from 
the fact that almost universally among plants the style of a pistil 
which has not been pollinated remains fresh and the stigma receptive. 
and persists for a much longer period than in one which has been 
pollinated. The effect of pollination in Zama seems to have no influ- 
ence on the length of time during which the scales remain open or on 
their endurance. The writer has found many cones developing nor- 
mally for several months after pollination in which only a few seeds . 
had set, and frequently mature cones have been found containing only 
two or three seeds. This infertility is doubtless due to the lack of 
pollination, as it has only been found in the case of Z. pumila at New 
Smyrna and Daytona, where microscopic examination has revealed a 
decided lack of pollen, many ovules being frequently found in a cone 
without a trace of pollen or pollen tubes. The plants of this species in 
these regions are scattering and pollination is frequently very imper- 
fect. 
_ £. floridana in the regions studied is very fertile, almost every 
ovule being fecundated and maturing a perfect seed. 
DEVELOPMENT OF PISTILLATE CONES. 
In the present paper the structure and development of the pistillate 
cones (figs. 2 and 6) will be discussed only so far as it bears on the 
question of development of the pollen tubes and fecundation. Ata 
later time the writer hopes to describe the development of the arche- 
gonia more in detail. 
At the time of pollination the ovules are ai 1 cm. long by 5 mm. 
broad (fig. 2). The single coat of the naked ovule is considerably 
