Dumortiera hirsuta (Sw.) Nees

Dumortiera hirsuta (Sw.) Nees, Nova Acta
Acad. Leop.-Carol. 12: 410. 1824.
Marchantia hirsuta Sw. Prodr. 145. 1788.
Marchantia irrigua Wilson; Hook. Brit. Fl. 2: 106. 1833.
Hygropyla irrigua Tayl.; Mackay, Fl. Hibern. 2: 54. 1836.
Dumortiera irrigua Nees, Naturg. Eur. Leberm. 4: 159. 1838.
Dumortiera hirsuta angustior G. t. N. Syn. Hep. 544. 1846.
Dumortiera hirsuta intermedia G. L.N. Syn. Hep. 544. 1846.
Askepos brevipes Griff. Not. PI. Asiat. 2: 340. 1849.
Dumortiera hirsuta irrigua Spruce, Trans. Bot. Soc. Edinb. 15: 566. 1885.
Thallus mostly 10-20 cm. long and 1-2 cm. wide, smooth or nearly so, the boundaries of the evanescent air-chambers sometimes indicated by delicate anastomosing lines on the upper surface; green tissue forming a smooth superficial layer of small cells; ventral tissue sometimes thinwalled throughout, sometimes with more or less distinct pits, sometimes with collenchymatous thickenings, the cells containing starchgrains except in the small-celled keel. Usually dioicous but sometimes monoicous and rarely with bisexual receptacles; male receptacle about 0.5 cm. broad, the upper surface smooth or w;ith a few bristles; female receptacle borne on a stalk 4-6 cm. long, the disc mostly 0.9-0.8 mm. wide, usually with marginal bristles only; spores reddish-brown, mostly 25-35 /j. in diameter; elaters 6-8 ju wide.
Type IvOCALITy: Jamaica.
Distribution: Pennsylvania to Florida and Alabama; Arkansas ; Mexico and Central America; Bermuda and the West Indies; also in South America, Europe, Africa, Asia, and the Pacific
Islands; on wet rocks and banks.