Rhizoids

Some articles on rhizoids, rhizoid:

Moss - Physical Characteristics - Description
... They do not have proper roots, but have threadlike (rhizoids) that anchor them to their substrate ... from their substrate through their rhizoids ... or Hepaticae) by their multi-cellular rhizoids ...
Evolutionary History Of Plants - Evolution of Morphology - Roots
... Rhizoids – small structures performing the same role as roots, usually a cell in diameter – probably evolved very early, perhaps even before plants colonised the land they are recognised in the Characeae, an ... That said, rhizoids probably evolved more than once the rhizines of lichens, for example, perform a similar role ... The rhyniophytes bore fine rhizoids, and the trimerophytes and herbaceous lycopods of the chert bore root-like structure penetrating a few centimetres into the soil ...
Riccia
... There are numerous unicellular rhizoids of two types on the ventral surface ... One type is called smooth and the other type is the pegged or tuberculated rhizoids these help in anchorage and absorption ... The inner surface of the smooth rhizoids is smooth while that of the tuberculate rhizoid will have internal cell wall projections ...