The Collaborative International Dictionary of English v.0.48:

Pennywort \Pen"ny*wort`\, n. (Bot.)
   A European trailing herb (Linaria Cymbalaria) with
   roundish, reniform leaves. It is often cultivated in hanging
   baskets.
   [1913 Webster]

   March pennywort, or Water pennywort. (Bot.) See under
      March.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Navelwort \Na"vel*wort`\, n. (Bot.)
   A European perennial succulent herb (Cotyledon umbilicus),
   having round, peltate leaves with a central depression; --
   also called pennywort, and kidneywort.
   [1913 Webster]