MARCHANTIA 61 
or irregular multiplication) alternating * with the rays, these, how- 
ever, опе in excess of Ше archegonia-groups. Each group of 
archegonia usually maturing several sporogonia, these enclosed 
by a common membranous 2-valved, fimbriate involucre, and 
each surrounded by a cleft pseudoperianth. Capsule borne on a 
seta as long as the pseudoperianth, dehiscing by several revoluble 
teeth or short valves. Spores small, smooth or nearly so. .Elaters 
long and narrow, 2-(1—3-) spiral. 
1. MARCHANTIA POLYMORPHA L. Sp. Pl. 1137. 1753. 
Thallus prostrate or ascending, rarely suberect, often in widely 
extended masses, oblong or linear, 2-10 cm. x .5-2cm., com- 
monly several times dichotomous, about 16 cells thick in the 
middle of the costa, becoming gradually thinner to the narrowly 
unistratose, mcstly somewhat undulate-crisped or irregularly short- 
lobed margin, areolae mainly rhombic, the pores scarcely visible 
to the unaided eye; the outer ventral scales oblong, obtuse, 
of 9 receptacle 2—7 cm. long, more or less pilose, that of the an- 
droecium usually shorter: capsule finally exserted, its wall uni- 
Stratose, with annular thickenings ; seta attaining length of 1-1.5 
mm.; spores yellow, 12-15 и, nearly smooth; elaters 300-600 у 
long, attenuate, 3-5 win greatest width, bispiral. 
On wet banks, in bogs, beside streams, about greenhouses, etc. 
Widely distributed in California but hardly common. We can 
name only the following localities: Berkeley; San Francisco ; 
- Mill Valley, Olema; near Duncan's Mills, Sonoma Co.; Mendo- 
сто (577); near Eureka; near Douglas City (1161), Trinity Со.; 
Sisson ; near Redding (Baker and Nutting) ; Silver Lake, Alpine Co, 
(Geo, Hansen); Jackson, Amador Co. (Geo. Hansen); San Bernardino 
Mts. (S. B. Parish, nos. 1445, 1446, 1693, 1694, 3369); vicinity 
of Pasadena (A. J. McClatchie). Also collected in California by 
r. Bolander, We have found no mature capsules in any Cali- 
fornian specimens and our description has been supplemented from 
material collected in Europe and in the eastern portions of the 
United States. 
* Exc. M. geminata М. В. ВІ. See Schiffner, Ueber exotische Hepaticae, Nova 
Acta Кз]. Leop.-Carol. Deutsch. Akad. Naturforsch. 60: 280, 281. 1893. 
