These are listed by
Common name. They are in the genus "Pelargonium". The
perennial geranium is in the genus "Geranium". Confusing,
huh? That's why we try to use the botanical names. Anyway, the first
section is P. peltatum (Ivy Geraniums).
The next ones down the list are P. x hortorum (zonal geraniums). 




