Monographs Details: Pseudocrossidium revolutum (Brid.) R.H.Zander
Authority: Buck, William R. 1987. Bryostephane Steereana: A Collection of Bryological Papers Presented to William Campbell Steere On The Occasion of His 80th Birthday. Mem. New York Bot. Gard. 45: 1-749.
Family:Pottiaceae
Discussion:One plant with six well preserved leaves, 1.38-1.48 m. The leaves are short (<1 m m ) and apiculate and have strongly revolute margins and massive costae that occupy about one-fifth ofthe leaf width at its base. Basal laminal cells are smooth, thick walled, and quadrangular to rectangular; upper cells are conspicuously papillose on both surfaces. The Columbia Bridge fossil closely agrees with illustrations of fossils from the Yukon (Janssens & Zander, 1980). Fig. 6e-g.