When Carl Meissner published his arrangement of Banksia in 1856, he demoted both of Brown's subgenera to sectional rank, maintaining B. sect. Isostylis (R.Br.) Meisn. as a monospecific taxon containing only B. ilicifolia. Meissner's rank and circumscription of Isostylis was retained by George Bentham in his 1870 arrangement for Flora Australiensis, but Bentham also published a putative variety of B. ilicifolia, B. i. var. integrifolia, based on specimens collected by Ludwig Preiss near the Swan River in Western Australia. This was later overturned.
