36 THE MICROSCOPICAL NEWS. 
Hoffmeister states that in Bryum argenteum the upper cell is 
divided once or twice by horizontal septa before the first oblique 
division, while in Phascum and Andrea this oblique septum is 
found immediately after the first horizontal one. The apical cell 
now forms two rows of segments by partition walls inclined alter- 
nately, and these segments are next divided by radial vertical walls, 
followed by further numerous transverse divisions. By this process 
the young sporogonium is transformed into a multi-cellular body 
which is usually fusiform, the lower end not participating in the 
growth in length, although a swelling of this lower end takes place 
in certain cases of Sphagnum, Archidium, and Phascum, such as 
usually occurs in the Hepatice. 
The apex now becomes inactive, and beneath it the capsule is 
formed as a spherical, ovoid, cylindrical, or frequently unsymmetrical 
swelling, which originates in the typical Mosses only after the elong- 
ation of the fusiform or cylindrical sporogonium, and after the 
raising up of the calyptra. 
This mass of homogeneous tissue presents at an early stage a 
differentiation into an amphithecium from which the wall of the 
capsule and of the spore-sac are derived, and a central endothecium 
corresponding to the future columella and sporogeneous layer or 
mother cells of the spores, which first of all become isolated and 
then divide, so as to form four spores. 
The contents of the mother cell begin to divide into two, but 
this bi-partition is usually not completed, the division into four 
taking place at once, and the preparation for the formation of 
spores takes place simultaneously everywhere within the same 
capsule. 
The ripe spores are roundish or tetrahedral, surrounded by a 
thin finely granulated exospore, which is of a yellowish, brownish, 
or purple colour, and besides protoplasm, they contain chlorophyll 
and oil. According to Lehimper the size of the spore is extremely 
variable. In Archidium, Ww here only sixteen are found in each 
capsule, they are about ;3, inch in size, while in the highly-de- 
veloped Dawsonia they scarcely attain =, inch. When kept dry 
the spores often retain their power of germination for a long time, 
but when moist they frequently germinate after a few days; those 
of Sphagnum after two or three months. 
The time necessary for the formation of the sporogonium varies 
greatly in the different species, but is usually very long in compari- 
son with the small size of the body concerned. The Pottia 
blossoms in summer, and ripens its spores in winter; the Funa- 
ria are perennially in blossom, and have constantly sporogonia in 
all stages of development, each occupying for its completion pro- 
bably two or three months. Phascum cuspidatum develops in the 
autumn from its perennial underground protonema, and ripens its 
