Flora of New Zealand Series

Raceme of few to many fls; floral bracts small, acute, hardly exceeding short pedicels. Per. glab., us. green; dorsal sepal uppermost in mature fls, broad and concave, much < ovary at fl.; lateral sepals almost equal in length but very much narrower, spreading or recurved, not connate; petals us. shorter and more obtuse, ± erect. Labellum about as long as other per.-segs, sessile, oblong to ovate, us. ± pendulous; calli us. paired at base, median and single near tip. Column short; wings membr., obtuse, attached to about mid-anther level; anther terminal, erect, almost entirely above stigma, ± hemispherical, pollinia not or obscurely bilobed, pollen granular; stigma broadly oval, slightly prominent; rostellum dark, its oval tip becoming detached with very short, threadlike stipe to which loosely coherent pollen masses adhere. Plants terrestrial, glab.; tuber globose to oval, often produced some distance from parent plant. Lf solitary; sheath long; lamina terete, ± hollow. Genus of perhaps a dozen spp., mainly Australian but extending also to S.E. Asia and to New Caledonia. N.Z. spp. probably all occur also in Australia.

Fls are recorded as fragrant in some spp.; stems and tubers emit a strong sweet smell noticeable even when no fls are present.

In N.Z. plants the calli of the labellum are of two kinds. That near the tip, if present, is wart-like with a roughly papillose surface and poorly defined limits. Near the base two more compact, smooth-surfaced calli are us. obvious; these form the anterior border of a transverse furrow behind and often round the ends of which the callus extends as a narrow band. Thomson (T.N.Z.I. 11, 1879, 422) suggests that this furrow might be a nectary.

Column-wings are us. membr. and only slightly thickened at their obtuse tips, but occ. one or both may terminate in a bilobed, almost anther-like structure. Below the stigma the free anterior margins of the two wings are connected by a transverse ridge.

Fig. 31. MICROTIS. Lettering as in fig. 20, p.103. © All rights reserved. [Image: 4X2P]