368. REPRODUCTIVE ORGANS OF LYCOPODIACE. 
. 
The spores, which are all of one kind, present a very curious 
structure ; they are little rounded or somewhat oval bodies, with 
three coats, the outer of which ultimately splits up, so as 
to form four elastic filaments, which are attached at one end 
to the smooth inner coats of the spore, and terminated at the 
other by a club-shaped expansion (jigs. 811 and 812). These 
Fie. 810. Eres oL1. Fic. 812. 
WF ND 
Fig. 810. Peltate stalked scale of a species of Horsetail (Hquisetum), bear- 
ing on its lower surface a number of sporangia or capsules.—F’g. 811. 
Spore of a Horsetail furnished with four elate7s, which are wound round 
it. The elaters are terminated by a club-shaped expansion.—Fig. 
812. The same spore in a dry state, showing the elaters in an uncoiled 
condition. 
spiral elastic filaments, which are called elaters, are at first 
wound round the spore (fig. 811), but they ultimately uncoil 
(fig. 812), and thus appear to assist in the dehiscence of the 
sporangium, and in the dispersion of the spore to which they 
are attached. 
When these spores germinate, a little pouch-like process pro- 
trudes from their surface by an elongation of their membrane ; 
this ultimately forms a green lobed flattened expansion, the 
prothallium, which differs however frum that of the Ferns in 
usually being furnished only with antheridia or archegonia—the 
prothallia therefore are said to be dicecious, instead of monoecious 
as ordinarily in Ferns. 
The male and female prothallia moreover differ somewhat in 
size, the former being the smaller of the two. As in Ferns also, 
from the germ-cell of the archegonium after impregnation by 
the antherozoids, a new plant is ultimately produced resembling 
in every respect that of the parent plant from which the spores 
were derived. As is the case in Ferns, therefore, we have in 
the Equisetacez also an instance of alternation of generations. 
3. LycopopIAcEZ OR Cius-Mosses.—The sporangia or cap- 
sules in the plants of this order are placed, like those of the 
Selaginellacez, in the axils or at the base of the leaves or scales, 
on short stalks. The leaves (jfig.12) thus bearing the sporangia 
or fructification are frequently collected together into a kind 
of scale, cone, or spike, while at other times they are scattered 
along the stem. The spores, like those of the Filices and 
Equisetaceze, are of one kind only, in which they differ from 
the Selaginellaceze, to which in other respects they are closely 
allied, the two orders until lately being placed together under 
the common name of. Lycopodiacez. 
tht 
oe “ui 
