212 BOTANICAL GAZETTE [SEPTEMBER 
The fertile megaspore nucleus moves to a higher position and 
rests for some time: The spindle of the first division is parallel to 
the axis of the embryo sac, and the two nuclei formed are always 
one above the other, as in figs. 8 and 9. Again at this division a 
temporary cell plate is formed. The second division occurs 
simultaneously in the two nuclei, and the spindles are at right 
angles to each other. The two upper sister nuclei and the proto- 
plasm about them become the synergids; of the other two, one 
surrounded by vacuolated protoplasm and a plasma membrane 
becomes the egg, and the remaining one is a free nucleus, in 
position and appearance the upper polar. 
Usually at these stages some remains of the sterile nuclei are 
still recognizable, but it is not always possible to be sure all three 
are present. They stain much less deeply than when first formed, 
taking little safranin and appearing to have a dark color of their 
own, independent of the stain. They vary considerably in size, 
and very frequently appear pitted or vacuolated, as in fig. 9. 
They are usually situated in the lower end of the embryo sac, as in 
figs. 8 and 11; fig. 9 is an exceptional case, since one of the sterile 
nuclei appears in the micropylar region. 
_Up to the tetrad stage the protoplasm of the embryo sac shows 
no tendency to unipolarity; it is coarsely granular and evenly 
distributed. But after the first division of the megaspore nucleus, 
when there is considerable enlargement of the sac, the protoplasm 
of the antipodal region becomes scant and stringy with large 
irregular vacuoles; that of the micropylar region is much denser, 
and the numerous vacuoles, which appear only at a late period, are 
small and globular. 
A third peculiarity of Clintonia is its comparative sterility. 
Though it blossoms freely, only a very small proportion of the 
flowers result in fruit. Propagation by vegetative outgrowths of 
the rhizome is the common means of multiplication. An examina- 
tion of 50 ovaries, collected one week after the opening of the 
flowers, disclosed no embryos and no certain proof that fertilization 
had occurred. In several embryo sacs one of the synergids was 
partially disintegrated, and in two cases two free nuclei were 
found below the egg apparatus, presumably derived from division 
