to support the application of such names to the parts, at
least in their ordinary signification. It seems more probable
that the larger bodies are the perfect spores, wliile the
smaller ones are merely abortive spores ; at least this is the
most reasonable explanation which has been offered. There
is, indeed, no doubt of the larger bodies being spores, since
they have been caused to germinate by different persons,
and a very detailed record of some experiments and observations
on this subject has been given by Mr. Yalentine.
According to Mr. Yalentine’s observations, the first external
sign of germination is either the appearance of four
cells projecting through the apex of the nipple-like point of
the spore, or a gradual swelling of that part, in which case
the enlarging cellular mass distends the conical point, and
at length appears externally with four of its cells projecting
beyond the general mass, and compressed into a quadrangular
form. Soon after the exposure of the entire germ,
little rootlets shoot out from one side; they are simply articulated
tubes, or elongated cells applied end to end. The
germ now gradually points in two places, which points gradually
lengthen, and each on dissection is found to consist
of a closed sheath, one containing a leaf, the other a root.
The young leaf, when rather longer than the spore, bursts
through its sheath, and the root protrudes before it is as
long as the spore. After this first leaf has grown to about
the length of a couple of lines, another issues from the
germ close to the former, and then a bud begins to be developed
from some indefinite part of the germ, hut, like the
leaves and root, from within the sheath. Sometimes this
bud appears immediately after the first leaf, and without the
production of a second. The bud is the rudimentary stem,
the first growth from it being a leaf exhibiting, though
slightly, evidence of gyration, and this is followed by a root
furnished with its own sheath.
It is one of the doctrines of botanists, that in what are
called Aerogenons plants— a group including Mosses, Club-
mosses, Scale-mosses, Horsetails, and Terns—germination
takes place at no fixed point, but from any part of the
surface of the spores; indeed this is one of the leading differences
between what are called spores, and the reproduc-
tive organs of flowering plants, caUed seeds. But Mr.
Yalentine maintains, that it is incorrect to say this of the
germination of Pilularia, for he is quite certain that in this
instance germination invariably takes place at a fixed
spot, which may be pointed out before germination has commenced.
I t is at a part of the spore, indicated by three ra