These placed the Liliaceae into one of the major subdivisions of the monocotyledons, the Liliiflorae. He was the first botanist to appreciate the distinction between monocotyledons and dicotyledons. The leaves of most monocotyledons lack petioles. There are more than 160 species of other monocotyledons and ferns. This nematode is extremely polyphagous, attacking both monocotyledons and dicotyledons. There are 265 "Monocotyledons" here distributed among 21 families and 139 genera. It describes the phototropic and gravitropic properties of emerging shoots of monocotyledons. Pseudopetioles occur in some monocotyledons including bananas, palms and bamboos. It is also found in Monocotyledons such as onions. Examples of non-host crops include grasses and many other monocotyledons. The taxonomic diversity of the monocotyledons is described in detail by Kubitzki. The native Australian flora contains many monocotyledons. Coleoptile is the pointed protective sheath covering the emerging shoot in monocotyledons such as grasses. Aquatic plants, especially the Monocotyledons, include a large number of polyploids. "Pondweeds and Bur-reeds and Their Relatives of British Columbia Aquatic Families of Monocotyledons".