1905] SHOEMAKER—HAMAMELIS VIRGINIANA 259 
is finally stored with food in the form of proteid grains, which shortly 
before ripening show numerous globoids (fig. 22) that disappear later. 
The ripe endosperm contains in its cells much oil along with proteid 
material, and in the cell walls there are imbedded numerous crystals 
of calcium oxalate (fig. 15). 
THE EMBRYO. 
The embryo begins growth comparatively late, so that the endo- 
sperm has already acquired some size before the first division of the 
egg occurs. The egg after fertilization becomes slightly imbedded 
in the tissue of the tapetal strand, and enlarges greatly. The first 
division is transverse and cuts off a small cell below and a large one 
above. By this continued cross division the suspensor may have 
five or six cells (fig. 23). The first division of the embryo is longi- 
tudinal. The embryo dissolves the endosperm in much the same 
Way as the endosperm dissolves the nucellus, and lies free in a cavity 
formed by the disintegration of the endosperm. At maturity there 
isa Straight axial embryo which extends from end to end of the seed 
and is richly stored with oil and proteid material in all its cells. 
The upper side of the cotyledons has already a well-developed palisade 
layer (fig. 24). 
INTEGUMENTS. 
The inner integument is at the beginning three cell layers in 
_ thickness, the innermost layer taking part in the formation of the 
inner seed coat. It early becomes filled with dense contents that 
stain blue readily (fig. 20), and finally shrink and become applied 
to the inner cell wall. The remaining layers are crumpled up so 
that they can only be made out with difficulty. 
The outer integument thickens greatly, and its cells elongate, 
taking a curved oblong shape. The cell walls then begin to thicken 
and the whole integument forms the outer seed coat which is moder- 
ately hard, black, and very resistant to water. The outer integument 
1S very smooth over the whole surface, except at the place of attach- 
ment of the funiculus, where there is a white saddle-shaped scar. 
The seed is ovoid, but very decidedly pointed at the lower end. 
The shape of the seed is a very important part of the discharging 
mechanism, 
