682 (82) HEPATIC. (LIVERWORTS.) 
Orper 140. HEPATIC. (Liverworrs.) 
Moss-like plants, of a loose cellular texture, usually procumbent, and emit- 
ting rootlets from beneath; the calyptra not separating Srom the base, but 
usually rupturing at the apex; the capsule not opening by a lid, containing 
spores usually mixed with elaters (which are thin thread-like cells, contain- 
ing one or two spiral fibres). — Vegetation sometimes Srondose, i. e. the 
stem and leaves confluent into an expanded leaf-like mass; sometimes 
foliaceous, when the leaves are distinct from the stem as in true Mosses, 
entire or cleft, 2-ranked, and often with an imperfect or rudimentary row 
Compe on the under side of the stem. Reproductive organs of two 
viz. antheridia and pistillidia, much as in Mosses (p. 607), variously 
one sid. The matured pistillidium forms the capsule, which is immersed 
in or sessile upon the frond, or borne on a long cellular pedicel, or 
attached to the under side of disk-like peduncled receptacles, and dehisces 
y irregular openings, by revolute segments at its apex, or lengthwise by 
2-4 valves: a columella is rarely present. The perianth is a tubular 
organ (sometimes absent), enclosing the calyptra, which is always present, 
and includes the pistillidium. Surrounding the perianth is the 
involucre (occasionally wanting), also a tubular organ, or leaves of particu- 
lar forms. The antheridia in the foliaceous species are situated in the 
axils of perigonial leaves; in the frondose species, scattered within the 
substance, or sessile upon the surface of the frond, or immersed in sessile 
or peduncled disk-like receptacles. 
Artificial Analysis of the Genera. 
I. Vegetation frondose (stem and leaves confluent in a frond). 
corer and columella wanting. 
1. RICCIA. Capsule yalveless, globular, immersed in the frond. Inyolucre none. 
2. SPHAEROCARPUS. Capsule ena globular, sessile on the frond. Involucre sessile. 
Elaters none, or imperfect : columella present. 
8. ANTHOCEROS. Capsule 2-valved, eimatteee fel Hinens, pedicelled. 
4. NOTOTHYLAS. il the frond 
ae ati Ua Feet 
+ Capsule irregularly, nearly sessile. Fertile receptacle peduncicd. 
Fertile receptacle 8 —10- 
le 4-5 ribbed. 
‘ertile é 
8. FEGATELLA. Fertile receptacle co 
9. REBOULIA. Fertile receptacle rarer 4-5 lobed ; the lobes acu’ 
10. GRIMALDIA. Fertile receptacle conical-hemisph — . se lobed ; ‘the ooh truncate, 
ulate 
12. PLAGIOCHASMA. Fertile receptacle minute, 2 - ea enc by we ascending in- 
olucres. 
+ + Capsule opening regularly by 4 valves, pedicelled. 
13. METZGERIA. 
