1899] SPORE-MOTHER-CELL OF ANTHOCEROS 107 
Prophase conditions of the nucleus show the presence of a 
mesh of delicate fibrils(filarplasm) around the structure. The 
nuclear membrane is at first irregularly angular, but finally two 
poles of a spindle are differentiated. 
The metaphase presents a spindle with flattened poles, 
entirely lacking bodies that might be interpreted as centrospheres 
or centrosomes. 
- There is a period of rest after the first mitosis when each 
daughter nucleus has a nucleolus and spirem thread. The two 
mitoses are, therefore, successive. 
The second mitosis presents structural features quite identi- 
cal with the first. 
- Thechromosomes are four in number in each mitosis. They 
appear to split longitudinally. 
All traces of the spindles become lost soon after each mitosis. 
~ The fully mature spore-mother-cell presents four chloroplasts, 
each with a single nucleus on the interior side. | The protoplasm 
segregates in these four regions of the cell, leaving spaces that 
are crossed by many anastomosing strands of cytoplasm. These 
strands cannot be traced from spindle fibers and appear to have 
He connection with filarplasm. 
The walls separating the cell contents into four spores are 
a. from films of protoplasm that appear between the chlo- 
2 asts with their respective nuclei. The films are formed by 
Cie of strands of cytoplasm that cross the spaces 
€ four regions of cell contents. 
The UNIVERSITY oF CHICAGo. 
LITERATURE CITED. 
95) Mosses and ferns. 
~~~ (98) On th 
€ structure and development of Dendroceros. Jour. Linn. 
Campgery ( 
33: 467 
FARMER and Re 
Phylla N 
FARMER (; 
EVES(’94) On the occurrence of centrospheres in Pe//ia epi- 
fes. Ann. Bot. 8: 210. 
9) Studies in Hepatice : On Pallavicinia decipiens Mitten. Ann. 
— (os) 5; | 
Pore formation and karyokinesis in Hepaticae. Ann. Bot. 9 : 363.- 
