| B. Macdonaldia. Column-wing extending behind the anther but shorter than it and not hood-shaped, variously lobed or crenate or fimbriate. | |
| Tall, slender, 9–18 in. high. Flowers 3–8, large, ¾–1 in. diam., blue-purple | 5. T. pulchella. |
| Flexuous and wiry, 4–10 in. high. Flowers 1–3, ½ in. diam., flesh-coloured | 6. T. imberbis. |
| C. Biaurella. Column-wing not extending behind the anther, but with 2 prominent erect lateral lobes. | |
| Flowers 3–6. Lateral lobes of the column-wing exceeding the short broad anther | 7. T. venosa. |
| Flowers 1–4. Lateral lobes of the column-wing not so long as the rather narrow anther | 8. T. uniflora. |
T. concinna and T. nervosa, Col. in Trans. N.Z. Inst. xx. (1888) 207, and T. fimbriata, l.c. xxii. (1890) 490, are unknown to me.
1. T. ixioides, Swz. in Vet. Akad. Handl. Stockh. xxi (1800) 228, t. 3.—Stem slender, 9–18 in. high. Leaf rather long but shorter than the stem, narrow-linear, thick, channelled in front. Flowers 2–8 or more in a raceme 2–6 in. long, rather large, ¾–1 in. diam. Sepals, petals, and lip broadly oblong or elliptic-oblong, obtuse or subacute. Column short, stout, not half as long as the perianth; the broad wing continued behind the anther and overtopping it, 3-lobed at the back and with a lateral lobe on each side at the front angle; lateral lobes the highest, pointing forwards and upwards, linear, tipped with a small dense tuft of cilia; the 3 intermediate lobes broader and shorter, truncate, denticulate or crenate, the middle one usually crested on the back. Anther rather narrow, pointed, much longer than the rostellum.—Hook. f. Fl. Tasm. ii. 6, t. 103b; Benth. Fl. Austral. vi. 317; Fitzgerald, Austral. Orchid. ii. pt. 3; Berggr. in Minneskr. Fisiog. Sailsk. Lund. (1877) 22.
North Island: Auckland—Kaitaia, R. H. Matthews! Whangaroa, Petrie! Bay of Islands, Berggren; Te Aroha and Rotorua, Petrie! (specimens not in a fit state for accurate determination, but apparently the same). September–November. Also in Australia.
2. T. longifolia, Forst. Char. Gen. 98, t. 49.—Very variable in size and degree of robustness, stout or slender, 3–18 in. high. Leaf short or long, often overtopping the flowers in short-stemmed specimens, narrow-linear or linear-lanceolate, varying in breadth from ⅛ to ¾ in. or even more, flat or involute, thick and coriaceous or fleshy, grooved and nerved. Flowers 2–16 in a raceme 1–6 in. long or sometimes solitary, variable in size, ⅓–¾ in. diam., colour varying from white to pink or blue. Sepals and petals oblong-ovate or ovate-lanceolate, acute or acuminate; lip usually broader and more obtuse. Column short, stout; the wing continued behind the anther and much longer than it, 3-lobed; the middle lobe the highest, broad, rounded, hood-shaped and projecting forwards over the anther, emarginate or shallowly 2-lobed, margins smooth,
