The Acanthaceae collected by Miss W. M. A. Brooke in Bolivia are listed. Five new species are described, viz. Stephanophysum brookeae, St. macrandrum, Sarotheca glutinosa, S. boliviensis and Lophothecium boliviense. Moreover, for the species belonging to the group Genuini Ebracteolati of Dipteracanthus Nees a new genus Ulleria is created. The following new combinations are proposed: Ulleria geminiflora (Ruellia geminiflora H.B.K.), U. angustifolia (Dipteracanthus angustifolius Brem.), U. surinamensis ( D. surinamemis Miq.), and further Stemonacanthus euanthus (Ruellia euantha Lindau), Arrhostoxylum kuntzei (Ruellia kuntzei Lindau), Sarotheca archeri (Justicia archeri Leonard), S. cystolithosa (J. cystolithosa Leonard) and Saglorithys polygonoides (J. polygonoides H.B.K.). Arguments for rejecting the delimitation of the genera Ruellia and Justicia adopted by Bentham and by Lindau are once more brought forward.