This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Herbaceous plants resembling the Asters, but the ray-florets are in several series. Nearly 100 species are known, from cold and temperate regions, but few of them are worthy of cultivation. The name is of Greek origin, signifying early old age, from spring, and old age.
2. E. specidsum, syn. Stendctis specidsa. - Of about the same stature as the foregoing, but with very numerous narrow ray-florets of a lilac-blue, and a yellow disk. The pappus of the outer florets is in one row, and of the inner in two. California.
E. alpinum var. grandi-fldrum with pink or reddish flowers, and E. Roylei with pale purple, very dwarf species, especially the latter, are grown by some amateurs.