species, is given at Plate VIII. C. From these I think it necessary to distinguish those species which, like Th. flexuosa, Endl. and Th. venosa, R. Br., have the anther incumbent, and not parallel with the stigma. These have in fact been separated by Mr. Gunn, who names the species met with in Van Diemen's Land Macdonaldia, after Mrs. Smith, née Macdonald, a lady who has examined the Orchidaceous plants of that island with great care, and from whom a most beautiful series of dried specimens has reached me through the good offices of Mr. Gunn. Of two of these with yellow flowers, viz. M. Smithiana,217 and antennifera, there are figures at Plate IX. B & C; much handsomer than either is M, variegata, with purple speckled flowers.
Next to Thelymitra in point of beauty are the species of Glossodia, Diuris, and Caladenia; among which are numerous species of the most exquisite forms and gayest colours. Glossodia Brunonis, Endl., has violet flowers two inches in diameter, spotted with brilliant purple; both it and G. emarginata224 have large roots, enveloped in numerous coarse skins,
(217) Macdonaldia. Perianthium regulare, patulum. Labellum sessile, foliolis conforme. Columna semiteres triloba, cucullata, laciniis nunc appendiculatis. Anthera terminalis, in stigma incumbens—Caulis flexuosus, foliosus, apice pauciflorus. (§ 2. Biaurella; cuculli lobo medio obsoleto, lateralibus appendiculatis.)
Macdonaldia Smithiana (Gunn mss.); caule unifloro 3-phyllo, floribus luteis, sepalis petalisque obtusis, cuculli trilobi glabri laciniis lateralibus nanis. (Van Diemen's Land.) Tab. IX. B.
(218) Macdonaldia concolor; caule triphyllo subbifloro, floribus luteis, sepalis petalisque obtusis, cuculli trilobi glabri laciniis lateralibus majoribus rotundatis. (Thelymitra flexuosa, Endl.)
(219) Macdonaldia antennifera (Tab. IX. C.); caule subtriphyllo paucifloro, floribus luteis, sepalis petalisque obtusis, cucullo a tergo appendicibus 2 carnosis clavatis emarginatis aucto.
(220) Macdonaldia (Biaurella) variegata; floribus purpureis, sepalis petalisque linearibus acuminatis, cuculli laciniis lateralibus lanceolatis subcarinatis intermediâ obsoletâ, antherâ carnosâ obtusâ elongatâ loculis brevibus semicircularibus membranaceis.
(221) Macdonaldia (Biaurella) spiralis; folio radicali spirali caulino solitario ovato, caule unifloro, floribus purpureis, cuculli laciniis lateralibus carnosis dolabriformibus intermediâ obsoletâ, antherâ obtusâ apice papillosa.
(222) Macdonaldia (Biaurella) cyanea; caule stricto subbifloro, floribus cyaneis, cuculli laciniis lateralibus apice dentatis intermediâ obsoletâ, antherâ apice trilobâ. (Van Diemen's Land.)
(223) Macdonaldia venosa.=Thelymitra venosa. R.Br.
(224) Glossodia (Elytranthe) emarginata; caule unifloro, columnæ alâ integer-
