THE GENUS BRYUM (BRYACEAE, MUSCI) IN MIDDLE ... - Arctoa

184
V. I. ZOLOTOV
1 mm
Fig. 77. Bryum cyclophyllum (Schwaegr.) B. S. G. (from Yaroslavl prov., Meshcheryakov, 7.VII.1924, LE): leaves.
Scale bar: 1 mm for all.
translucent, formed by thin-walled elongate
cells; costa thin, weak, green or yellowish-green,
ending in leaf apex or below. Laminal cells thinwalled,
not porose, in upper leaf rhomboid-hexagonal
to rhombic, 32-56 x 16-24 μm, in midleaf
lax, rhomboid to regularly hexagonal, 48(-
80) x 16-28 μm, above smaller and shorter, at
base rectangular to elongate-rectangular, 60-160
x 16-28 μm, green; basal marginal cells longer
than juxta-costal ones.
Perichaetial leaves lanceolate, acuminate,
concave, margin plane, costa ending below leaf
apex. Seta 2-3 cm long, fuscous to red, thin, rigid,
twisted when dry, abruptly curved below capsule.
Capsule pendulous, light brown, dull, ca. 2
mm long, 0.8-0.9 mm thick, shortly pyriform,
symmetric, contracted below rather broad
mouth when dry, neck broad, nearly as long as
urn. Operculum large, low-conic to highly conic-convex,
with short apiculus, brownish-yellow,
slightly glossy. Annulus 3-rowed. Peristome inserted
at urn mouth, 420-440(-450) μm high.
Exostome teeth narrow, gradually acuminate, at
base ca. 100 μm wide, below fuscous-yellow to
pale, above hyaline; border rather broad, 12-14
μm wide; median line zig-zag-shaped; fundus
of same color as teeth or brighter, 60-70 μm
high, broadened; ventral trabeculae 19-22. Endostome
free, translucent to pale yellowish; basal
membrane to 1/2 of endostome length; seg-