52 _ BOTANICAL GAZETTE [JANUARY 
tudinal axes transverse to it (figs. 23, 26, 27, 28). Soon after 
these divisions have occurred the spores assume a spherical form 
and increase greatly in size. 
Fics. 24, 25. Some of the mother cells broken down and lying more or less 
attached to the tapetum. X 1375. 
GERMINATION OF THE MICROSPORE. 
The walls of the spore thicken, and, after a short period of 
rest, the nucleus shows signs of the approaching germination 
(jig. 30). In fig. 31 is shown a case of division of the micro- 
spore nucleus. At the ends of the spindle are distinct granules 
of unequal size, while near the spindle in the cytoplasm are other 
granules, apparently of the same nature, so far.as appearance and 
staining reaction can testify. The spores at this time are usually 
well filled with refractive food masses. 
Usually, though not always, the first division results in the 
placing of one daughter nucleus near the wall of the microspore 
(fig. 32). The nucleus so placed is the nucleus of the genera 
tive cell. This cell is small, slightly lenticular in outline, and 
stains a little more deeply than the large cells of the germinat- 
ing microspore (figs. 3 3-39). It remains more or less closely 
applied to the wall of the spore for a short time, then after 
moving a little distance from the wall divides (fig. 30): The 
spindle of this division is smaller than that of the preceding one 
