58 



MARCIIANTIACEiE. 



[AcilOGENS. 



Ohdeu XVI. MAKCHANTIACEJE.— Liverworts. 



tt .• m i.„< r:„ 7 (1789) • DC. Fl. Fr. 2. 415. (1815) ; Agardh Aph. 104. (1822) ; Nees ab 



l:elK ; I 1 ",' • ,. ri v Fliira .'l 2B5. < 183.ii ; HMto 1 '. Bri«tfi ™, vol. ii. p. 97. (1838) ; Bischoff 



:..,,,,,-. M Cur. xvii. pars 2. (1836) ; Ann, des 8c. 2 ser. 4. 309. (1836).- 



Mi,r'-i ■>...,.,-. ee and TargioniacesB, i'd. pr. Emit. Gen. xx - Marchanties and Targ.onie.e, 



'.\,., /.,/„,- „ .-t.-Marchaiitiea:, Taylor in Linn. TratU.17.377. 



I ) i v . . nosis.— Spore-casesvalvelm, or bursting irregularly, without operculum, hut with claters. 



Plants growing on the earth or trees in damp places, composed entirely of cellular 



emitting roots from their under-side, and consisting of an axis or stem which 



is leafless, but bordered by membranous expansions, which 



sometimes unite at their margins, so as to form a broad lobed 



t, d, having a distinct epidermis pierced by stomates. An- 



theridia either immersed in the frond, or placed on disk-like 

 sessile or stalked peltate receptacles. Pistillidia lurking within 

 involucres, either placed below the edge of the frond, or on the 

 edge or under-side of stalked heads. Spore-cases stalked, open- 

 ing by irregular fissures, or by separate teeth. Spores globose, 

 with elaters. 



With these plants organization advances another step. To the 

 spores of the Crystalworts are added spiral threads or elaters 

 for their dispersion ; and various lacerated membranes sur- 

 rounding the spore-cases seem to be imitating the calyx and 

 corolla of perfect plants. There is still, however, a want of 

 true leaves, which are fused, with the stem, into a 

 frond. The principal part of the order has the spore- 

 cases raised on a long stalk, and clustered into a head ; 

 but this character is missing in Targionese, which 

 Endlicher regards as a distinct order. In these 

 plants, as in Mosses and Charas, each cell of what 

 are called the antheridia contains a body resembling 

 an animalcule of the genus Vibrio, which moves about 

 rapidly in water, as soon as it is liberated from its 

 birth-place. Germination takes place by an universal 

 increase and enlargement of the spore, which becomes 

 lobed, as it were, by the swelling of the cellules, and 

 is afterwards nourished by the emission of a radicular 

 fibre. The original development of Ferns and Liverworts is much the same. Fl. Bras. 

 i. 299. 



The Liverworts differ from Crystalworts in having elaters and involucrate spore-cases, 

 and from Scalemosses or Jungermanniacete, in the want of power to separate their spore- 

 cases into distinct valves. 



Natives of damp shady places in all climates; two were found in Melville Island. 

 The only atmospheric condition to which they cannot submit is excessive dryness. 



Little is known of their uses. De Candolle thinks it probable that the larger kinds 

 will be found to resemble foliaceous Lichens in their qualities. A few are slightly 

 fragrant, with a subacrid taste. They have been employed in liver complaints, but their 

 use bo ms a mere superstition. It is, however, alleged that Marehantia hemisphserioa 

 has really proved advantageous in dropsical affections. 



Fig. XXXVIII. 



Suborder I. Maim ha \ - 



tca.— Spore cases cap!- 



[nvolucels mem 



brnnous, regularly slit. 



Qrlmaldia, Radd. 

 Pleurochiton, Radd. 

 Syndonitce, Radd. 

 "i.i . ( lord. 

 Duva 



phyllum, Neet, 



1 mil .t .1! 1:1 . 



Bypcnantron, Cord. 



GENERA. 



Dtetjfoehiton, Cord. 

 Fegatella, Radd. 



ConoctphcUllt, Vaill. 



t'l/iiin; phalum, Wigg. 

 Lunularia, Midi !. 



twickia, Bowd. 

 Plagiochasma, lehm. 



Otiona, Cord. 



'irirkia. lii.sch. 



Aitonia, Font. 



Ruppinia, L. f. 

 Antrocephalus, Lehm. 

 ltcbuuillia, Radd. 



AslerMa, Palis. 



Rh iik ioca rpon , Cord. 



Achiton, Cord. 



? Mesoregtna, Cord. 

 Bauteria, Neet. 



Hampea, Nees. 

 Dumortiera, Nees. 



Hyrophila, Mack. 



Hygrophyla, Tayl. 



" Spathysia, Nees. 

 Marehantia, March. 



.Preissia, Nees. 



thomiucarpon, Cord. 



[ Suborder II. Tarqionkm. 

 - i^pore-cases suimiar- 

 ginal, solitary. Involu- 

 cels wanting. 



Targionia, Michel. 

 Cyatbodium, Lehm. 

 t Carpoboiut, Schvein. 



Astromarchantia .Nees \ ... „, ... &„, , ,„ 



Chlamidium, Cord. | Athalamia, Falcon* . 



Numbebs. Gen. 15. Sp. 20 ? 



Eqwis< tacew. 

 Position. Ricciacea;.— M arch am iace^e. — Jungermanniacese. 

 Lichenaceee. 



XXWill— l. Marehantia commutata, natural size; 2. a head of spore-cases; 3. a section of 

 the disk which bean the spore-cases ; 4. elater ; 5. granular spore 



