BOTANICAL GAZETTE. 351 
base in a considerable and abrupt enlargement. The tapetal 
cells, t, are unusually large and appear, in longitudinal section, 
columnar. In each lies a nucleus which is almost as wide as the 
cell, At both ends of the embryo-sac the tapetal cells become 
like the other cells of the nucellus. In the basal enlargement of 
the embryo-sac lie the three antipodal cells, a, one of which is 
usually a short distance above the other two. There are fre- 
quently two nuclei, en, en', belonging to the embryo-sac, near its 
middle. The pointed apex of the sac is occupied by the syner- 
gide, s, s', which are correspondingly long, nucleated near their 
upper ends and vacuolated near their lower. A little below the 
lower ends of the synergide lies the oosphere, 0. It is notice- 
ably more granular than the synergide and its nucleus is some- 
what larger. A layer of protoplasm lines the embryo-sac and 
bridles extend in various directions between the egg-apparatus, 
the nuclei of the embryo-sac and the antipodal cells. 
_ the mature pollen-spore is marked externally with numerous 
minute elevations (fig. 10), hardly more than thickenings of the 
cuticle, and 3-12 thin spots for the exit of the pollen tubes. At 
each thin spot in the extine there is a corresponding thickening 
of the intine. 
he mature pollen-spore possesses two nuclei, the larger 
round one, the vegetative’ nucleus (vn, fig. 11), occupying the cen- 
ter of the cell, while the spindle-form, generative nucleus lies to 
one side, I have been able to demonstrate both of these nuclei 
only one case, when, after staining with borax-carmine, 
crushed the cells (fig. 12). In several cases I have found the 
Vegetative nucleus after treatment with acetic-methyl-green, and 
in other cases I have seen the generative nucleus in the pollen 
— (fig. 13). The difficulty of distinguishing the nuclei in 
'§ Species is greatly enhanced by the markings on the walls, 
d 
. is 
T staining wit je-iodine-green, but it is not so in t 
Species, g with acetic-iodine-green, 
senerative nuclei. The vegetative nucleus is therefore not 
destroyed in the spore, but passes early into the tube, where it 
1 In this 5), which is ex- 
homenclatu er (Neue Untersuchungen, P- ), 
in Borhereverse of shat generally uoed and even (ne reverse of that given by Strasburger 
°N m, p. 495 
yeue Unters, p. 34. by 
