62 BOTANY. 
imbedded in the frond, or situated on rounded, sessile, and stalked receptacles. 
2. Pistillidia, either inclosed in involucres and solitary, or occurring at the 
edge of the frond, or on the lower side of stalked peltate expansions. Thecze 
or developed pistillidia, having no operculum, opening irregularly, or by 
four valves. Spores often mixed with spiral filaments called elaters. He- 
terorhizal in germination. ‘Terrestrial plants found in damp places, or 
inhabiting water; some having a moss-like appearance. They are natives 
both of cold and warm climates, and are generally distributed over the 
globe. 
Sub-order 1. Jungermanniee, or scale mosses. Frondose or foliaceous 
plants, terrestrial or on trees. Capsule dehiscent lengthwise into four valves. 
Jungermannia, the principal genus, is represented by many species: Gym- 
noscyphus, one of the true Jungermanniez, is represented in pl. 54, fig. “48, 
by G. repens. 
Sub-order 2. Marchantiee. Frondose and terrestrial ; neha growing 
in wet places, with the fertile receptacle raised on a peduncle, capitate or 
radiate, bearmg pendent calyptrate capsules from the under side, which 
open variously, not four-valved. laters with two spiral fibres. Ex. 
Marchantia polymorpha (pl. = jig. 44), very common jn shaded, moist 
places. 
Sub-order 3. Anthocerotee. Terrestrial frondose annuals with the fruit 
protruded from the upper side of the frond; perianth none. Capsule pod- 
like, single or double-valved, with a free central columella. Elaters none or 
gimperfect. Ex. Anthoceros punctatus (pl. 54, fig. 42), found on wet slopes 
and the sides of ditches throughout the United States. 
Sub-order 4. Ricciee. Mostly frondose floating little annuals, with both 
kinds of flowers, and the fruit immersed in the frond. No involucre, perianth, 
nor elaters. Capsule bursting irregularly. Ex. Riccia. 
Sub-order 5. Monoclee. Fruit, solitary capsular, opening laterally by a 
longitudinal slit. © Elaters, mixed with spores. Vegetation, foliaceous or 
frondiform. Ex. Monoclea. 
OrverR 5. Musci, Mosses. Plants having a distinct axis of growth, often 
giving off branches or innovations; no vascular system. Leaves minute and 
imbricated, entire or serrated, sometimes with condensed cells, in the form 
of ribs or nerves. _ Reproductive organs of two kinds: 1. Antheridia, 
cylindrical or fusiform stalked bags, containing powdery matter and plhy- 
tozoa, and mixed with empty jomted filaments or paraphyses. 2. Urn- 
shaped pistillidia, inclosed at first within a calyptra. which is ultimately 
carried up with them, leaving often a sheath round the bottom of the fruit 
stalk. These pistillidia finally become the thecz, or spore-cases, supported 
on a stalk or seta, which has leaves at its base, called perichetial leaves ; 
on removal of the calyptra the theca is found to consist of a case with an 
operculum or lid, which, when it falls off, shows the mouth of the urn, either 
naked or crowned with a peristome, consisting of one or more rows of teeth 
(in number four, or a multiple of four), distinct or united in various ways. 
In the centre of the theca is a columella, and the bag formed between it and 
the parietes of the theca contains spherical cells, called spores, each of 
62 
