Dicranodontium flagellaceum

Dicranodontium flagellaceum (C. Mull.) R. S. Williams
Dicranum fiagellaceum C. Mull. Syn. 2: 597. 1851. Campylopus fiagellaceus Mitt. Jour. Linn. Soc. 12: 77. 1869. Leptotrichum Pinetorum C. Mull. Linnaea 38: 627. 1874.
Appearing dioicous, or autoicous with male flowers on slender branches distant from the perichaetium, rarely on short branches close to the perichaetium: plants in broad mats with somewhat tomentose stems 1-2 cm. high, often bearing flagellate blackish-jointed branches clothed with rather short, stout-pointed leaves: stem-leaves more or less falcate-secund or erect-flexuous, lanceolate-setaceous, subtubulose, mostly 4-5 mm. long, the point serrulate on the back and margins about one half down; costa nearly one half excurrent, toward the base about one third the width of the leaf, in cross-section near the middle of the leaf showing a narrow band of stereid-cells on the dorsal side, interrupted by large outer cells, on the ventral side a more or less evident stereid-band with or without differentiated outer cells; alar cells reddish or hyaline, more or less inflated and auriculate, the cells of the lower part of the blade pale, thin-walled, rectangular, mostly 8-12 n wide and 40-50 /t long toward the costa, toward the margin narrower, not forming a distinct border; inner perichaetial leaves about the length of the outer, convolute nearly one half up, rather gradually narrowed to a rough point: seta mostly 10-15 mm. long, straight or more or less curved or flexuous, especially when moist: capsule oblong to cylindric, about 2 mm. long; annulus large; peristome-teeth narrow, at the base about 26 M wide, the outer plates vertically striate below, papillose above; lid with a subulate beak a little shorter than the capsule : calyptra reaching to near the base of the capsule : spores nearly smooth, about 13 ^ in diameter.
Type locality: Cerro San Andres, Michoacan. Distribution: Mexico.