The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in a series of monographs and texts, including The Evolution and Classification of Flowering Plants (1968; 2nd edition, 1988) and An Integrated System of Classification of Flowering Plants (1981) (see ). Cronquist's system places flowering plants into two broad classes, Magnoliopsida (dicotyledons) and Liliopsida (monocotyledons). Within these classes, related orders are grouped into subclasses. While the scheme was widely used, in either the original form or in adapted versions, many botanists now use the Angiosperm Phylogeny Group classification for the orders and families of flowering plants, first developed in 1998. The system as laid out in Cronquist's An Integrated System of Classification of Flowering Plants (1981) counts 64 orders and 321 families in class Magnoliopsida and 19 orders and 65 families in class Liliopsida.