Microtis R.Br.
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.
Key
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]](https://data.landcareresearch.co.nz/Image/4X2P/SysPortalPreview)
