404 
pulverulent ones are at least not anthers, as has been supposed ; for in Isoetes 
the pulverulent inner thecae have the same organisation, even to the presence of 
what has been called their stigma, as the outer granular ones ; so that, if Isoetes 
has sexes, it will offer the singular fact of its anther having a stigma. 
Geography. In geographical distribution these follow the same laws as 
Ferns, being most abundant in hot humid situations in the tropics, and espe- 
cially in small islands. As they approach the north they become scarcer ; 
but even in the chmate of northern Europe, in Lapland itself, whole tracts 
are covered with Lycopodium alpinum and Selaginoides. 
Properties. Lycopodium clavatum and Selago excite vomiting ; the 
powder contained in the thecae is highly inflammable, and is employed in 
the manufacture of fireworks. According to Vastring, they are likely to 
become of importance in dyeing. He asserts, that woollen cloths boiled with 
Lycopodiums, especially with L. clavatum, acquire the property of becoming 
blue when passed through a bath of Brazil wood. Lycopodium Phlegmaria 
is reputed an aphrodisiac. 
GENERA. 
Lycopodium, L. 
Plananthus, Beauv. 
Stachygynandrum, 
Beauv, 
Diplostachyum, 
Beauv. 
Gymnogymim, 
Beauv. 
Lepidotis, Beauv. Hoffmannia, W. 
Selaginella, Beauv. Tmesipteris, Bernh. 
Psilotum, Swz. Isoetes, L. 
Bei'nhardia, W. 
Order CCLXXXII. MARSILEACE^. 
The Pepperwort Tribe. 
Rhizocarp^, Batsch. Tab. Aff. (1802) ; Agardh Aph. 111. (1822). — Rhizosperm^e, Roth. 
DC. FI. Fr. 3. 577. (1815). — Hydropterides, Willd. Sp. Pl.b. 534.(1810). — Mar- 
STLEACE^, R. Brown Prodr. 166. (1810); Grev. FI. Edinens. xii. (1824); Ad. 
Brongn. in Diet. Class. 10. 196. (1826; DC. and Duty, 542. (1828); Martins, Ic. 
PI. Crypt. 121. (1834). 
Essential Character. — Creeping plants. Leaves petiolate and divided (or petioles 
destitute of lamina), rolled up in vernation. Reproductive organs enclosed in leathery 
involucres, and of two kinds, the one consisting of membranous sacs, containing a body or 
bodies, which germinate, the other of similar sacs, containing loose granules. — \_Stem and 
leafstalks filled with longitudinal cells. A central simple fascicle of vessels composed of 
scalariform ducts and prosenchyma, enclosing in the middle a quantity of 'elongated cells 
containing starch. Leaves with nerves, veins and stomates. Martins.'} 
Affinities. The tribe to which Pilularia and Marsilea belong consists 
of creeping plants, having the circinate vernation of Ferns, with their repro- 
ductive organs in close leathery cases, called involucres, springing either 
from the root, or from the petioles of the leaves. These involucres are sepa- 
rated internally by membranous partitions, and contain oval bodies of two 
kinds, one of which has been called anther, and the other capsule. 
Beautiful figures of Marsilea vestita and polycarpa have been published by 
Hooker and Greville, at t. 159 and 160 of their noble leones Filicuin. From 
these it is clear that the involucre of the genus consists of an involute frond, 
of the same degree of analogy to the true frond as a carpellary leaf to a true 
leaf. It further appears that the reproductive bodies arise from the veins 
of this involute frond, and are therefore analogous, as to position, to the sori 
of Ferns. What the nature of these bodies may be, is not so obvious. They 
are represented as being of two kinds; the first, called the capsule (?), being 
an oval stalked case, having two integuments, of which the outer is reti- 
