The scientific study of the genus in the late eighteenth century was accompanied by detailed descriptions with Botanical illustrations, such as those of William Curtis (1787) and Sims (1803), that appeared in Curtis' Botanical Magazine, with illustrations by Sydenham Edwards. Other illustrations are found in monographs such as those of Haworth (1809) and Sabine (1830), illustrated by Charles John Robertson. The largest collection is found in the most comprehensive monograph, that of Maw (1886). other sources include the portfolios of plates, such as the survey of the plants of France by Masclef (1891). At that time only C. sativus and C. vernus were included in the Flora of France.
