Slender Ladies Tresses (S. Gracilis) is slender, has its flowers in a single-ranked 1-sided or slightly twisted raceme; lip green, with a white wrinkled margin. Leaves small, ovate basal. Found in dry ground from N. S. to Manitoba and southwards.
A. Heart-leaved Twayblade.
B. Large Twayblade.
Heart-Leaved Twayblade (Listera Cordata) belongs to a genus containing five species. They may readily be recognized by the two heart-shaped or ovate leaves clasping the flower stem, oppositely, about half way up. The flowers are either madder-purple as in the present species, or greenish.
Like most of the Orchids, they are largely or wholly dependent upon insect aid for fertilization. The weight, or shock, of an alighting insect on the broad lip causes a small gland within the flower to rupture and cover the pollen, just below with a sticky fluid that causes it to adhere to the head or body of the insect and thus be transferred to the next flower.
The stem of this species is from 3 to 10 in. high. At the top is a few flowered raceme; the sepals and petals are similar and spreading; the lip is drooping, longer, two-cleft and madder-purple in color. This species flowers during June and July in swampy woods from N. J. to Colo, and northwards to the Arctic coast.
Twayblade (Liparis Lilifolia) , although having the same common name, is of a different genus. It is a more attractive plant, having two broad basal leaves and larger flowers with a broad ovate lip. It grows in woodland from Me. to Minn, and southwards.
Coral Root (Corallorrhiza Maculata) is so named because of its angular, branching, brownish, corallike root. The scape is from 10 to 18 in. high; its only leaf appears as a sheath near the base. The flowers are madder-purple, in a loose raceme; the sepals and petals are small, similar and ascending; the lip and column are white, spotted with purple, the former being two-lobed. There are five species of Coral Root, all destitute of green foliage, and differing only slightly in the flowers. They are found in spruce woods from Me. to British Columbia and southwards.