Allium ursinum umbel of six to 20 white flowers only, lacking the bulbils produced by some other "Allium" species such as "Allium vineale" (crow garlic) and "Allium oleraceum" (field garlic). It flowers in the British Isles from April to June, starting before deciduous trees leaf in the spring. The flower stem is triangular in cross-section and the leaves are broadly lanceolate similar to those of the lily of the valley ("Convallaria majalis"). It is native to temperate regions of Europe, from Britain east to the Caucasus. It is common in much of the lowland British Isles with the exception of the far
Dactylorhiza majalis streaks, or dots. The spur is bent slightly downwards and is not quite as long as the ovary. The tuber has a palmate division and an irregular shape. The western marsh orchid has a karyotype of two sets of forty chromosomes. The seed of this orchid contains no endosperm for the embryo. Therefore, germination can take place only by means of infection with a root fungus (mycorrhiza). In 1828 Ludwig Reichenbach described the western marsh orchid as "Orchis majalis". The name became the basionym after Peter Francis Hunt and Victor Samuel Summerhayes transferred the species to the genus "Dactylorhiza" in