9 Germinated pollen in pollen chamber

10 Small sterile and large fertile ovules

7 Micropyle

8 Longitunal section of upper portion of ovule at pollination

5 Pollination drop

6 Longitudinal section of ovule at pollination

3 Ovule; pollination drop

4 Pollen in pollination drop

1 Ovulate cone at pollination

2 Induction of pollination drop

2：Kept at high humidity.
3-5：Taken indoors (pollination drops are smaller in the field).
4：Pollen sinks in pollination drip and reaches directly or indirectly to pollen chamber. The meniscus of the drop may carry the pollen at outer fringe of the micropyle to its inner fringe, when the drop recedes. The mechanism of drop secretion is unknown.
5：The apical portion of ovule is waxy (hydrophobic), and this feature keeps the drop spherical (functional).
6：ｆｇ-female gametophyte, i-integument (later seed coat), n-nucellus；light microscopic photograph.
7：Pollination drop is secreted from the inside of ovule and forms droplet on the micropyle.
8：Pｃ-pollen chamber; pollen chamber is formed by degeneration of nucellar cells；SEM photograph.
9：Pollen exine is attached to pollen tube until fertilization stage；SEM photograph.
10：Unpollinated ovules seem to be abortive.　

Notes