Epiphytal. _Stems_ short, tufted, densely leafy. _Leaves_ distichous, recurved, rigid and leathery in texture, broadly ligulate, channelled, obliquely cut away at the acute apex, evergreen. _Racemes_ axillary, many-flowered. _Flowers_ huge (fully four and a half inches across), and from the parts lying in one plane having a _primâ facie_ resemblance to those of _Odontoglossum vexillarium_; _dorsal sepal_ roundish, obovate (one and three-quarter inches by two inches), of a delicate rosy blush on both surfaces, slightly stained with buff-yellow at the base; _lateral sepals_ divergent, but overlapping, obliquely and broadly obovate (two and a quarter inches by three inches), pale nankin on the outer surface, the inner of a deep greenish yellow, with about nine longitudinal prominent veins of a bright purplish crimson, extending from the base to within a quarter of an inch of the tip, and connected by transverse lines of the same colour, breaking off into dots towards the margin; _petals_ much smaller than the sepals, obovate-cuneate (one and a quarter inch by one and a half inch), the principal portion rosy blush like the dorsal sepal, but the lower edge tinged with yellow, and bearing a few purple spots; _lip_ small, less than an inch broad, spurless, the basal part (hypochil) concave, pale purplish red, ribbed exteriorly with nankin-yellow, the front lobe (epichil) shortly stalked, bluntly heart-shaped, with the tip strongly recurved, chocolate-purple, with three prominent ridges or crests extending from base to apex, where the middle ridge just falls short of the two outer ones. _Column_ very short, pale yellowish, almost touching the sides of the concave basal lobes of the lip. _Ovary_ hexangular, pink. Vanda Sanderiana, _Reichenbach fil._, in _Gardeners’ Chronicle_, N.S., xvii., 588; _Id._ xx., 440, figs. 67 (habit), 68 (inflorescence). Esmeralda Sanderiana, _Reichenbach fil._, in _Gardeners’ Chronicle_. N.S., xvii., 588 in note.