358 BOTANICAL GAZETTE [ Novemser 
Fig. 3. A section of the anther wall at a still later stage ; on the extreme 
outside is the epidermis; then two layers the inner one of which will later 
disintegrate ; the fourth layer is the tapetum the cells of which often contain 
two nuclei ; and farther inside are shown a few archesporial cells. 
Fic. 4. A portion of the anther wall at nearly the same stage as in fig. }, 
showing the division of the tapetal nucleus. 
Fic. 5. A slightly later stage of the same in which the daughter nuclei 
formed in fg. ¢ are in the process of fusion. 
Fic. 6. A portion of the mature anther wall; the outer layer is the 
epidermis, the next below is the endothecium with spiral markings on the 
walls; and farther inside a disorganized mass composed of the tapetum and 
the one or two layers just outside. 
Fic. 7. An archesporial nucleus in the resting stage ; the linin network 
contains granules of chromatin of various sizes. 
Fic. 8. Synapsis, the projection at the left is the nucleolus. 
Fic. 9. Last stage of synapsis ; the spirem ribbon is opening out, and 
between its meshes are chromatin masses of various sizes ; the nucleolus at 
the left. 
Fic. 10, The spirem ribbon with chromatin granules imbedded in the 
linin. 
Fic. 11. The spirem ribbon after longitudinal segmentation, and cut in 
lengths by the section knife. 
1G. 12. Chromosomes still showing the \double nature; dissolution “ 
the nuclear membrane. 
Fic. 13. The multipolar spindle with chromosomes in various views. 
Fic. 14. The bipolar spindle and nuclear plate; the chromosomes 
the end appear -+-shaped, from the side view more elongated. 
Fic. 15. The + separates into v-shaped segments which are seen -_ 
ing toward the pole. 
Fic. 16. During the resting stage before the second division, 
viewed from the pole; the chromosomes remain distinct. 
Fig. 17. The nuclear plate of the reducing division ; 
so numerous that their form can be determined only with difficulty. 
Fic. 18. A chromosome on the nuclear plate, side view. 
Fig. 19. Pole view of a chromosome which is bent y-shaped. 
Fic. 20. End view of fg. 78. 
Fic. 21. A rare case, where fig. 20 has opened out along ¢ 
forming a ring. 
FiG. 22. v-shaped segments ready to pass to the poles. 
from 
the nucleus 
the segments ar 
