Hutchins' Ulota Moss

Ulota hutchinsiae (Smith) Hammar, Monogr. Orthotr
Ulot. Suec. 27. 1852.
Orthotrichum americanum Beauv. Prodr. Aeth. 80. 1805.
Orthotrichum Hutchinsiae Smith, Eng. Bot. pi 2523 1814.
Orthotrichum strictum Brid. Bryol. Univ. 1: 289. 1826.
Weissia americana Lindb. Musci Scand. 28. l°/9. ,
Ulota americana Limpr. in Rab. Krypt.-Fl. 42: 21. 1890. Not U. americana Mitt. 1864.
Plants dark green at the tips, dark purplish-brown to almost black below, 1-2 cm. high, rigid, brittle; leaves closely imbricate when dry, crowded, not contorted nor crisped, 1.5-2.5 mm/long, 0.4-0.6 mm. wide at the base, the upper narrower, concave-carinate, lanceolate to ovate-lanceolate or oblong-lanceolate, obtuse to obtusely acute, the margins more or less recurved; costa nearly or quite percurrent; upper leaf-cells papillose, very thick-walled, subcircular to elliptic, the lumen 8-10 n in diameter; median basal cells strongly colored, very thickwalled, linear, the lumen often little wider than the walls; marginal basal cells with thinner walls, often also colored; seta 2-4 mm. long; capsules long-exserted, oblong-ovoid, the «~ir «^«t /mm lone, the urn about 1.7 mm. long, pale yellowish-brown; old capsules sub-
* Credited bv Bridel to "Web. Tab. Syn. Muse", presumably Weber & Mohr, Tabula exhibens Muscorum frondosorum genera (1813); this work has not been available. cylindric and much darker in color, becoming strongly 8-ribbed when dry; calyptra very hairy; exothecial cells differentiated along the ribs; operculum conic-rostrate; peristome-teeth 16, united in pairs, finely papillose, erect at dehiscence, becoming reflexed later, perforate on the median line above; segments 8, slender, of two rows of cells, about half the length of the teeth; spores about 15 p. in diameter, maturing in early summer.
Type locality: Near Bantry, Eire.
Distribution: On calcareous rocks, rarely on trees; eastern United States and Canada, south to Georgia, west to the Rocky Mountains ; Arizona (Bar tram) ; Europe.