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Within the Orchidaceae, ''Hormidium'' was originally a subgenus of the genus ''Epidendrum'', but was later raised to a full genus. It is now considered not to be distinct from the genus ''Prosthechea'', of which it is a synonym. Most of the species of ''Hormidium'' have been transferred to ''Prosthechea'', although others are now classified in ''Encyclia'', ''Epidendrum'', ''Homalopetalum'', and ''Lepanthes''. == Taxonomy == In 1841, John Lindley used the name ''Hormidium'' for one of the subgenera into which he divided the genus ''Epidendrum''. He described the subgenus as having pseudobulbous stems, sessile flowers and with the lip (labellum) of the flower joined (adnate) to the column. Later, in 1861, Heinrich Reichenbach concluded that the subgenus ''Hormidium'' was superfluous. In 1883, George Bentham and Joseph Hooker raised ''Hormidium'' to a full genus.〔, p. 524f.〕 They distinguished ''Hormidium'' from the other pseudobulbous species of ''Epidendrum'' with at least a partially adnate labellum, and specifically mentioned only four species, two of which are now retained in ''Epidendrum'', one which is now placed in ''Homalopetalum'', and one which is now placed in ''Lepanthes''. Because the genus ''Encyclia'' features non-adnate labella, and because the genus ''Prosthechea'' features labella which are only partially adnate (and therefore do not quite meet Lindley's criteria for ''Hormidium''), Bentham and Hooker's description is useful: :"The plant is a small epiphyte. The pseudobulbs and rhizome are covered with membranaceous sheathes. The pseudobulb bears one or two small leathery or fleshy leaves. The flowers are small (or larger, in the case of ''Hormidium sophronitis''), born on a short raceme. The floral bracts are small. The sepals are of equal lengths, partially closed or completely open, the dorsal sepal free at the rear and the lateral sepals adnate to the base of the column forming a small "ladle". The petals are similar to the sepals or very narrow. The labellum is adnate to the column to its apex with completely erect lamina, either trilobate or lacking any divisions. The column is short with a dilated margin. The clinandrium is short and truncated. The terminal, operculate, slightly kidney-shaped anther leans against the column and carries four pollinia. The flattened egg-shaped pollinia are distinct from each other." ''Hormidium'' is now considered not to be distinct from the genus ''Prosthechea'', of which it is a synonym. Most, but not all, of the former species of ''Hormidium'' have been transferred to ''Prosthechea''.〔Search for "Hormidium", 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hormidium」の詳細全文を読む スポンサード リンク
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