134 BOTANICAL GAZETTE [AUGUST 
Fic. 15.—Pollen grain after pollination has taken place, beginning to 
elongate. 
Fic. 16.—First division of micros; 
Fic. 17 ican generative cell an larger tube cell sections from first 
division of mi 
Fic. 18.—Stage pilus more advanced than preceding figure; tube 
nucleus passing into tube and cytoplasm becoming vacuolated. 
Fic. 19.—Somewhat older tube, showing generative cell in forward end of 
tube enlarging before division, and large number of starch grains in cytoplasm 
of tube. 
Fic. 20.—Generative cell has divided into basal stalk cell and anterior 
body cal. which already shows denser cytoplasmic contents than stalk cell 
Fic. 21.—Passage of —_ and. ideale cells mato tube, 
1G. 22.—Portion ofa l secti showing 
female gametophyte in nucellar tissue and several pollen tubes whtelé have 
penetrated nucellus to female gametophyte. 
Fic. 23.—Body cell at time of maturity, with laterally placed nucleus and 
delicate cytoplasmic radiations along periphery, together with stalk cell 
nucleus and tube nucleus. 
scar nate ‘Late stage in division of body cell; lenticular cell plate is shown, 
lizati lon in of cell. : 
Fic. 26.—Mature phyte, consisting of two unequal male cells, 
stalk cell nucleus, ad abe wockeda. 
“PLATE XIt | 
Fic. 27.— _ Patitulas ove which iching pollen tube | ssed 
to female gametophyte. 
2 ‘IG. 29 gf gee tend £ BAe | hae Pe a4 ee ee 
female ee peseiese: nucellus nearly to base of female oe 
_tophyte. 
Fic. 30.—Portion of le in which femal developed 
from an upper. megaspore, pollen tube ete pated pst gamete. 
_ Fic. 31.—Two pollen tubes have pushed past female gametophyte 
enlarged below it; non-functioning lower megaspore is recognizable. a 
Fic. 3 2—An ovule which contained no less than 22 pole tober ‘the 
