1130 HEPATICJ^:. 



Suborder II. MAUCHANTlACE.E. 



Genus 45. MARCHANTIA, March. jiJ. 



ilarchantia, March, fil. in 3Iem. Acad. Paris. (17l;5)- Micheli Gen. (1720); 

 Linn. Arc. 



Fronds flesh}-, rarely membranaceous, opaque, often ver\Mjroad, 

 with a broad diffused midrib, densely radiculose, apex emarginate 

 or dichotomous ; no postical branches; antical face reticulate or 

 porose ; postical face with scales on each side, 2-5 seriate. 

 Inflorescence dioicous, terminal. Peduncle arising from a sinus 

 in the apex of the expanded forking frond, elongate, bi- (very 

 rarely 3) canaliculate. Capitulam more or less convex, many 

 lobed, radiating, rarely subentire, above smooth, below with 

 narrow scales. Involucre with several (2-5) flowers. Perianth 

 with apex 3-5-fid. Capsule globular, stipitate, exserted, pen- 

 dulous, dehiscent by 4-8 laciniate segments, often revolute. 

 Elaters long, slender, attenuate at each end, 2-, 3- (very rarely 

 1-) spiral. Spores medium-minute. Andra^cia pedunculate, 

 peltate, radiate or lobed. Gemma? lenticular borne in a cup- 

 shaped receptacle. 



Marchantia polymorpha, Linn. Sjj. PL 11, 1G03 (1753). 



Dioicous, c?espitose, medium to large in size, dull green on 

 the antical side, on the postical brownish. Fronds closely imbri- 

 cate, procumbent, dichotomoiisly branched, flattened, branches 

 short, margin entire, sinuous, midrib broad, thick and very 

 distinct; radiculose, rootlets numerous of two kinds, the stronger 

 but simpler kind are the root hairs which penetrate the sub- 

 stratum and perform the same functions as the true roots of 

 higher plants ; the otliers are more delicate and have internal 

 thickenings arranged spirally ; these delicate rhizoicls do not 

 penetrate the sub-strnium but lie flat up to the postical surface 



