What genus honors John Parkinson, Parkinsonia or Rumohra?
Parkinsonia: Parkinsonia , also Cercidium , is a genus of flowering plants in the pea family, Fabaceae. Parkinsonia:  The name of the genus honors English apothecary and botanist John Parkinson (1567–1650). Rumohra: Rumohra is a genus of ferns in the family Dryopteridaceae.
Parkinsonia