Assertion: moss's cell | /r/CapableOf | cover adaxial frontof the leaf
Facets:
Source sentences:
text: The leaves of Polytrichastrum formosum (shown here) and Polytrichum commune have close-packed longitudinal columns of photosynthetic cells covering the adaxial (front) of the leaf, but in Polytrichastrum the leaf is flatter with a v-shaped protruding nerve on the back, whereas the backs of the leaves of Polytichum are distinctly rounded.