403 
These plants are known from true ferns by the following most important 
characters. Their stem is solid with a central axis composed of spiral or 
annular vessels, not hollow, and without sinuous woody plates ; their leaves 
are in most case sundivided and veinless, and instead of bearing the thecae on 
the leaves, they bear them in the axils of the leaves. Lycopodales are just 
intermediate between Mosses and an extinct race of trees called Lepidodendra 
which connected them with Coniferse. See Fossil Flora, vol. 2. p. 51 . 
Order CCLXXXI. LYCOPODIACE^. The Club-Moss Tribe. 
Lycopodine-®, Swartz Synopsis Filicum (1806) ; R. Brown Prodr. 164. (1810) i Agardh 
Aph. 112. (1822); Greville Flor. Edin. xii. (1824); Martins Ic. pi. crypt. 37. 
(1834). — Lycopodiace^, DC. FI. Fr. 2. 257. (181.5) ; Ad. Brongn. in Diet. Class. 
9. 561. (1826). — Iroetr®:, Bartl. Ord. Nat. 16. (1830). 
Essential Character. — Usually moss-like plants, with creeping stems and imbri- 
cated leaves, the axis abounding in annular ducts ; or stemless plants, wdth erect subulate 
leaves, and a solid cormus. Organs of reproduction axillary sessile thecae, either bursting 
by distinct valves, or indehiscent, and containing either minute powdery matter, or spo- 
rules, marked at the apex with three minute radiating elevated ridges upon their proper 
integument. 
Affinities. Intermediate as it were between Ferns and Coniferse on the 
one hand, and Ferns and Mosses on the other ; related to the first of those 
tribes in the want of sexual apparatus, and in the abundance of annular ducts 
contained in their axis ; to the second in the aspect of the stems of some of 
the larger kinds ; and to the last in their whole appearance, Lycopddiacese 
are distinctly characterised by their organs of reproduction. These are gene- 
rally considered to be of two kinds, both of which are axillary and sessile, and 
have from 1 to 3 regularly dehiscing valves, the one containing a powdery 
substance, the other bodies much larger in size, which have been seen to 
germinate. In conformity with the theory, that all plants have sexes, the 
advocates of that doctrine have found anthers in the former, and pistils in the 
latter ; but, as in other similar cases, this opinion is entirely conjectural, and 
founded upon no direct evidence : all that we really know is, that the larger 
bodies do germinate, and, if we are to credit Willdenow, the powdery particles 
grow also. He says he has seen them. I think it is hardly to be doubted 
that the latter are the abortive state of the former. According to Salisbury, 
in the Linnean Transactions, vol. 12. tab. 19, Lycopodium denticulatum emits 
two cotyledons upon germinating ; but, supposing this observation, which 
requires confirmation, to be exact, it is much more probable that the two lit- 
tle scales so emitted are primordial leaves than analogous to cotyledons. The 
genus Isoetes is by some referred to Marsileacese, to which it forms a transi- 
tion. I foUow De Candolle and Brongniart in referring it here. Delile has 
published an account of the germination of Isoetes setacea, from which it 
appears that its sporules sprout upwards and downwards, forming an inter- 
mediate solid body, which ultimately becomes the stem, or cormus ; but it is 
not stated whether the points from which the ascending and descending axes 
take their rise are uniform ; as no analogy in structure is discoverable between 
these sporules and seeds, it is probable that they are not. Delile points out 
the great affinity that exists between Isoetes and Lycopodium, particularly 
in the relative position of the two kinds of reproductive matter. In Lycopo- 
dium, he says the pulverulent thecae occupy the upper ends of the shoots, and the 
granular thecae the lower parts : while, in Isoetes, the former are found in the 
centre, and the latter at the circumference. If this comparison is good, it will 
afford some evidence of the identity of nature of these thecae, and that the 
