It is represented in Britain by two genera, Geranium (crane's-bill) and Erodium (stork's-bill), to which belong nearly two-thirds of the total number of species.
In Erodium the members of the outer whorl are reduced to scale-like structures (staminodes), and in Pelargonium from two to seven only are fertile.
1); in Erodium and Pelargonium each coccus remains closed, and the long twisted upper portion separates from the central column, forming an awn, the distribution of which is favoured by the presence of bristles or hairs.
Magellanicum are found in the antarctic. Erodium contains 50 species (three are British), most of which are confined to the Mediterranean region and west Asia, though others occur in America, in South Africa and West Australia.