Structure, etc., of Eptphegus Virginzana. 391 
being flattened against each other (Fig. 17 h-i). In slightly 
older anthers, these tetrads appear as four separate balled- 
up nucleated masses of cytoplasm, lying in a clear shining 
mucilaginous-looking mass. At this stage a great number 
of disintegrating cells are lying around next the anther 
wall, a degenerating tapetum probably. 
The mature pollen grain shows a double layer of clear 
refractive thickening round its wall. Within is densely 
stained protoplasm. It is invariably divided into two dis- 
tinct masses, separated by a considerable space (Fig. 17 k). 
One mass is very small relatively, and lies flattened against 
the wall. It contains a small clear elliptical nucleus, with 
a large dense nucleolus, and chromatin scattered along the 
nuclear membrane. The larger protoplasmic mass shows 
two slight lobings. A clear vacuole fills most of one lobe. 
The other contains a large nucleus, spherical in outline, with 
considerable chromatin and a large dense nucleolus. This 
is probably to be regarded as the prothallial nucleus, while 
the small flattened nucleus is the generative nucleus. 
Somewhat later, the pollen tube is seen emerging. The 
spore wall looks thin and eaten away at one point, then a 
bulging of the protoplasm occurs here. The tube pushes out 
into the bulging here, the small nucleus lying against its side 
wall. The large nucleus is seen remaining in the pollen cell, 
and probably disintegrates there, as it is not observed later. 
The pollen tube grows across and enters the stigma, push- 
ing its way between the cells and down the style. Two 
nuclei now appear in it, undoubtedly resulting from a divi- 
sion of the generative nucleus, and forming the two sperm 
nuclei that are later noted in the macrospore cavity. 
DIFFICULTIES OF GERMINATION. 
It is surmised that for successful germination, the seed 
of Epiphegus requires contiguity with the beech-root. The 
seed falls upon the soil and is carried probably but a little 
distance below the surface. At least this would be inferred 
