12 THE SPHAGNACE& OR PEAT-MOSSES OF 
CHAPTER III. 
THE VEGETATIVE SYSTEM. 
GERMINATION OF THE SPORE. 
To the investigations of Nageli and Hofmeister are we principally 
indebted for our knowledge of the development of the plant, and 
Professor Schimper further observed them under cultivation, and 
found that on damp earth the spores germinated in two to three 
months, and that the proembryonal cell rarely broke through the 
exospore or outer coat in less than five weeks. 
The development proceeds under one of two forms, according 
to the local conditions in which the spores may happen to be 
placed at the time; thus, if they be immersed in water, the ger- 
minating proembryo assumes the form of a confervoid protonema, 
somewhat akin to that of true mosses, but more elongated and 
less branched ; from one end of this the young plant arises by a 
tuberculoid aggregation of cells, while the other extremity becomes 
a root, or one of the middle cells becomes the mother cell of the 
new plant. But if the spore germinate on the damp ground, the 
proembryonal cell goes on subdividing in a horizontal plane, and 
the result is a lobed green prothallium like that of Egudsetum, con- 
sisting of a single layer of cells; this hepaticine frond throws out 
radicles from the under surface and margins of the lobes, and 
quite resembles a plant of Blasca or Anthoceros. After a while, 
cells aggregate here and there at the margins of the lobes and form 
rudimentary plants, which support themselves partly from the 
prothallium, partly by radicles; in the plants growing in water 
also, the radicles attach themselves to any fixed body, and thus 
securely anchor the plants until they are in a condition to take care 
of themselves. . 
The roots in the young plants of Sphagnum precisely resemble 
those of frondose mosses, consisting of slender elongated cells with 
oblique transverse septa, and their functions are also similar, for 
they serve both for support and nutrition; as soon, however, as 
the branches are produced, a portion of them become pendent and 
