Pterostylis R.Br.


Terrestrial herbs with small globular tubers and succulent slender roots. Leaves often in a rosette and ± ovate, or cauline and lanceolate to linear; the rosette in many species dissociated from the flowering stem, and often absent at flowering time. Flowers solitary, or from few to many in a terminal raceme. Perianth usually green but often red with red-brown tints. Dorsal sepal very concave, usually much incurved; lateral margins dove-tailed into or connate with those of the petals to form a hood over the column (Fig. 44). Lateral sepals ± connate in their lower portions to form a lip in front of the column, or deflexed against the ovary, or rarely spreading; lower portions divergent and often tapering into fine points. Labellum usually small, ovate to linear or rarely filiform, attached to the projecting foot of the column by a moveable claw which is usually ± irritable and occasionally furnished with long translucent hairs, usually undivided, frequently with a curved brush-like appendage below its junction with the column foot. Column elongate inside the hood and ± attached to the median line of its wall; the upper part with transluscent wings on either side of the rostellum; the base prolonged into a nearly horizontal foot. Anther very blunt, with 2 pollen sacs; pollinia 4, powdery. Stigma often prominent, near the middle of the column; rostellum higher up, just below the pollinia; caudicle absent.