John Stanley Beard, in "Plant Life of Western Australia" (p. 29-37)[1] gives a short history of the various mappings.
Gardner modified Diels' description, adding the Northern Province, which comprised the Kimberley and Pilbara districts.
[1][3] Subsequent work by Beard and others[4][5][1] gave the current set of provinces used by Florabase[6] in its descriptions of plants.
(See, for example, the entry[7] where Parsonsia diaphanophleba is described as being found in Beard's South-West Province.)
Beard's provinces are: Many of the subregions above have now been modified to give IBRA regions, among which are: