42 - BOTANICAL GAZETTE 



[JANUARY 



access to the interior of the ovar>' through an open style which is more 



o± conducting cells, the lower ones 



mass 



extending well do^^^l into the cavity of the ovary \fig 14) The 

 poUen tube enters by the micropyle, and a number of sections were 

 obtained showing it penetratmg the nucellus. One section showed 

 the male nucleus and oosphere {fig, 15), but careful search failed to 



case of the fusion of the second male nucleus with 



endosperm nucleus. As it is known 



j; 



{fig' -f^), it seems 



mbryo sac and approaches the endosoerm 



ENDOSPERM 



The first^ divisions from the endosperm nucleus result in the 



ifiS- ^7)' These increase in 



number 



until 



embr^^o sac {fig. 18). They are well defined and usuaUy multi 



showing 



When 



com 



begin to appear, and 



nucleus is separated from its neighbors by a well-defined wall. Active 

 growth contmues rnitfl the embryo sac is filled with endosperm, which 

 now begins to crowd the surrounding cells. The lateral vestiges of 

 the nuceUus disappear, as a result of this pressure, and the inner integu- 

 ment IS stretched until it becomes finally nothing more than a thin 

 limiting membrane surrounding the endosperm. The outer integu- 

 ment remams intact, its growth keeping pace with the growth of the 

 endosperm. The persistent tip of the nuceUus 



and even increases in size. The cells in the base 



remams 



lus are greatly crowded, and many of them break do™. When the 

 endosperm has reached its fuU size, it is about 3»» in length, and 

 consists of two weU-defined parts (fc .p). The ^■pper pai (*) 

 consists o cells w«h thin but well-defined walls and at fct a distinct 

 nudeus ; later they are filled with starch grains. In the lower part 

 of the endosperm there is developed a large vacuole (i). 



EMBRYO 



In the specimens e^mined, the Itrst di^'ision of the oospore does 

 : occur mitil the formation of endosperm is well under wav. As 



