Drummond Moss

Drummondia prorepens (Hedw.) O. Jennings,
Mosses W. Pa. 116. 1913.
Gymnostomum prorepens Hedw. .Sp. Muse. 35 j. J801. Drummondia clavellata Hook. ; Drummond. Musci Am. 62. 1828.
Plants in thin dense mats, dark green to almost black below; primary stems long, reaching 10 cm or more in length, sending up numerous short (2-10 mm. long), crowded, densely foliate ^u.i M «« rWlv aooressed when dry, erect-spreading when moist, 1-2 mm. long, oblonglanceolate to ovate-lanceolate, acute to narrowly obtuse, concave, carinate, firm, the margins plane or widely inrolled, entire; costa strong, almost percurrent; upper leaf-cells small, the lumen 7-10 /i in diameter, rounded, incrassate; basal cells scarcely different except at the very insertion, where they are often larger and more translucent; in the perichaetial leaves basal cells elongate over a considerable area, becoming rectangular near the insertion; dioicous, the archegonia and antheridia in terminal buds; seta erect, 2-3 mm. long; capsules erect and symmetric, ovoid-globose, about 1-1.3 mm. long; calyptra large, conic, cucullate, without hairs; exothecial cells parenchymatous, thin-walled, irregular, oblong to hexagonal; stomata apparently lacking; operculum conic-rostrate, the beak long, oblique; mouth of the capsule bordered by several rows of small, thick-walled cells; peristome of 16 short teeth (about 60 p long), truncate, smooth, persistent; inner peristome and annulus lacking; spores 60-90 y. in diameter, maturing in spring.
Type locality : Pennsylvania (Muhlenberg) .
Distribution : On the bark of trees ; New England to Ontario, south to Georgia, Alabama, and Missouri; frequent in the northeastern United States.

Drummondia prorepens là một loài Rêu trong họ Orthotrichaceae. Loài này được (Hedw.) E. Britton mô tả khoa học đầu tiên năm 1894.