Abstract:

There are two prothallial cells in Cathaya, but their formation is different from

that of the other genera of Pinaceae.  A primary prothallial cell is cut off first and the division

of this cell gives rise to 2 prothallial cells which remain intact in mature pollen grains. 3-celled

pollen grains are formed.  The interval between polination and fertilization is about 13 mon-

ths.  The two sperms are different in size.

Key words: Cathaya, male gametophyte