This section is from the book "Wayside And Woodland Blossoms", by Edward Step. Also available from Amazon: Wayside And Woodland Blossoms: A Guide To British Wild-Flowers.
This is the common Purple Heath of our elevated heaths and commons, distinguished from its relatives by its smooth stems and leaves; the latter exceedingly narrow, their edges curled under, and arranged around the stems in whorls of three leaves, with clusters of minute leaves in their axils. The flowers also are in whorls, and either horizontal or drooping. The sepals are four in number, green; the corolla in one, egg-shaped, with four short lobes around the mouth. The stamens are eight, bearing two-celled crested anthers, each cell opening at the side to discharge its pollen, and having a toothed process at its base; the cell-openings of one anther being pressed against those of neighbouring anthers. The style is dilated at the top, and its surface is the stigma. Flowers July to September.
Another common species is The Cross-leaved Heath (E. tetralix), with downy stems and leaves; the leaves in whorls of four, and fringed with hairs, margins rolled under as in cinerea. Flowers pale-rosy, drooping, gathered into a dense head at the summit of the stem. The corollas are pale, almost white, on their under-sides. The anthers like those of cinerea, but with two longer processes from the base of each. Bees visit the Heath plants for their plentiful honey, and in pushing their long tongues into the flower in search of it touch their heads against the stigma, which partially blocks the mouth of the corolla. The tongue has to press against one or more of the anther processes, which has the effect of dislocating the series of anther-cells, and allowing the pollen to fall through the opening upon the bee's head, which is thus ready to fertilize the next flower it visits. This species may be found growing with E. cinerea, but usually selects the dampest, boggy spots on the heath. Flowers July to September.
There are two other species, E. vagans and E. ciliaris, but they are confined almost entirely to the county of Cornwall; the former distinguished by its bell-shaped, not egg-shaped, corolla, and anthers and pistil hanging outside; ciliaris marked by its leaves being fringed with hairs, each hair tipped with a gland.
The name is from Ereikh, the ancient Greek name for heath or heather.
Fine-leaved Heath. Heather-Ling.
The Ling is distinguished from the Heaths by the botanist because its bell-shaped corolla is concealed by the longer, equally coloured calyx leaves, and below these are four bracts which resemble a calyx. Its leaves are triangular, very minute and densely packed, overlapping each other. Like the Heaths its flowers are persistent, and are to be found bleached but preserving much of their original form, nine or ten months after they opened. The anthers are short, and contained within the corolla, but the style is long, and protrudes. The tough wiry stems attain considerable size in the highlands of Scotland, where they serve many useful purposes. It flowers from July till September. C. vulgaris is the only species. The genus gets its name from the Greek Kalluno, to beautify or adorn, an epithet which all who have visited the moorlands in its flowering season will admit is well-bestowed.