In his paper, Mendel described eigh

In his paper, Mendel described eight single gene characters
of pea, of which he investigated the segregation of
seven. The eighth is the ‘purple podded’ character determined
by the gene Pur on linkage group I. He also discussed
the segregation of three traits (tall versus short,
green versus yellow pods and inflated versus constricted
pods) in common bean (Phaseolus vulgaris) that are likely
orthologues of the corresponding characters he studied in
pea. For both species Mendel used additional species
names (such as Phaseolus nanus or Pisum saccharatum)