It is significant as an early treatment of the biogeography and floristics of the flora of Australia; for its contributions to plant systematics, including the erection of eleven currently accepted families; and for its presentation of a number of important observations on flower morphology.
Karya ini penting sebagai perlakuan dini biogeografi dan floristika flora Australia; atas sumbangsihnya bagi sistematika tumbuhan, termasuk penyusunan sebelas famili yang saat ini masih digunakan; dan atas presentasinya sejumlah pengamatan penting tentang morfologi bunga.