1914] HUTCHINSON—MALE GAMETOPHYTE OF ABIES 149 
division into stalk and body cells takes place six or seven days before 
pollination. At this time the prothallial cells are at their maximum 
size. 
. F man n 
3 
< Fics. 1-3.—A bies balsamea: fig. 1, ripe pollen grain; figs. 2, 3, at time of shedding, 
Owing divisions of prothallial cells; p, prothallial cells; 6, body cell; s, stalk cell; ¢, 
tube nucleus; all x610. 
Frequent variations in the number of prothallial cells occur. 
€ maximum number is four (figs. 2 and 4), but three are of more 
frequent occurrence (figs. 3 and 5). The division, as indicated by 
the position of the daughter cells, is anticlinal, either in or at right 
angles to the plane of the wings, hence they are best seen in a polar 
view. The presence of two derivatives of a prothallial cell, wher 
