ABSTRACT:

The great aroid systematists were Schott and Engler. Schott was the first specialist but his systematic ideas were pre-Darwinian, focusing on similarities rather than possibilities of descent. Engler, for all his accomplishments, specialized in aroids and his post-Darwinian ideas dominated aroid systematics for nearly a century. Recently two systems were independently proposed. Bogner & Nicolson's is essentially a revised Englerian system. Grayum's is a totally new synthesis. The phylogeny of existing aroids will never be fully known but continuing and new work may bear on the speculations that necessarily underlie differences between the recent systems.