Sorry meant pelagorniums. Am a rotten speller.
oakleif

Yes, they are two separate but related genera. Pelargoniums (note spelling) or what are commonly referred to as windowbox or annual geraniums are native primarily to South Africa, thus their tenderness in more temperate or colder climates. True geraniums, often referred to as cranesbill from the shape of their seedheads, are native to temperate areas above the equator, hence their hardiness in colder climates.

Examining both side by side, one can easily see the similarities in both leaf form and flower, but there are scores of species and hybrids of both and often the differences are very distinct. For one, there are very few double flowered geraniums, while this is extremely common with the pellies. And too, it is more common for the pellies to hold their flowers in clustered infloresences, while geraniums tend to have individually held flowers or spaced along a flowering stem.

There are lots of other distinctions as well, but those are the most obvious.