Assertion: fern's leaf | /r/CapableOf | bear single vein
Facets:
Source sentences:
text: Further, horsetail (Equisetum) leaves bear only a single vein, and appear to be microphyllous; however, both the fossil record and molecular evidence indicate that their forebears bore leaves with complex venation, and the current state is a result of secondary simplification.
text: The club mosses and spike mosses have true stems and roots, and the tiny leaves, called microphylls, have a single vein.