Douglasiane. N. O. Hepatice. 
TAB. CLVIII. 
MARCHANTIA TRICHOCEPHALA. 
F'rondibus membranaceis opacis ex areolatis oblongis pinnatifido- 
lobatis, pedunculis elongatis, receptaculo hemispherico 5—6- 
lobo supra pilis longis erectis fuscis hirsutissimo. 
Haz. Sandwich islands. D. Douglas, (n. 71). 
This well marked species of Marchantia is one of the com- 
paratively few species of plants, discovered by Mr. Douglas in 
the Sandwich islands, which have reached this country. Its 
fronds form widely spreading patches which are imbricating, 
dark-green, opaque, membranaceous, lobed in a_pinnatifid 
manner, the lobes oblong, obtuse, sinuato-pinnatifid, the texture 
is very compact, almost like that of Jungermannia epiphylla, and 
‘no reticulations are visible to the naked eye. Peduncles at or 
near the apex of the segments of the frond, at first short and 
hairy, at length an inch or an inch and a half long, naked, 
terminated by an hemispherical involucre, clothed above with 
copious long erect hairs, the margin about 5-lobed, and bearing 
beneath as many pendent capsules, filled with seeds and spiral 
filaments. 
Fig. 1. Portion of the fertile frond. f. 2. Receptacle with a 
sules. . 3. Spiral filaments. f, 4. Seeds or sporules :—magnijied. 
