plant kingdom Haeckel (1866) - plants
   Division Protophyta Sachs 1874 - primitive plants
     1 Class Schizophyceae Cohn 1879 - blue-green algae
     2 Class Schizomycetes Nägeli 1857 (Approved Lists 1980) - bacteria and related forms
     3 Class Microtatobiotes Philip 1956 (Approved Lists 1980)