broadly truncate or abruptly acute at the apex, minutely erose except on the basal margins; disc rather abruptly narrowed below the lateral lobes, 3-nerved, bicarinate with the keels extending from the centre of the lateral lobes almost to the middle of the mid-lobe. Column cylindric, slightly arcuate and abruptly bent back near the summit, about 1.9 mm. long measured on the dorsal surface, with an elongated stigmatic orifice, extended into a relatively long foot. Anther conic-semiovoid. Pollinia eight, obliquely complanate-pyriform.

Octomeria minor differs from O.rigida Rodr. in its small vegetative proportions, less acuminate floral segments, 3-nerved petals and membranaceous lip.

BRITISH GUIANA, Essequibo River, Moraballi Creek, near Bartica. Nearly at sea-level, "Epiphyte on the entomologist's tree (Morabukea). Fl. cream." August 24, 1929. N. Y. Sandwith 112 (TYPE in Herb. Kew.)

Octomeria parvula C. Schweinfurth sp. nov.

Herba pusilla, epiphytica, caespitosa. Radices fibrosae, numerosae. Caules pauciarticulati, unifoliati. Folium crassum ut videtur, lineari-ellipticum. Inflorescentiae axillares, pauciflorae. Flos membranaceus. Sepala lanceolata vel ovato-lanceolata, trinervia, persimilia. Petala paulo minora. Labellum in circuitu ovato-ellipticum, prope medium trilobatum; lobi laterales parvi, auriculiformes; lobus medius multo major, acutus, dentatus vel denticulatus.

Plant small, slender, caespitose, about 8 cm. or less tall. Roots fibrous, glabrous, numerous. Stems filiform, decumbent at base, 1- to 3-jointed, 4.2 cm. or less long, unifoliate, entirely concealed by close tubular sheaths which are commonly evanescent. Leaf linear-elliptic, apparently very fleshy in the fresh state, shortly petioled to subsessile, acute, erect or erect-spreading; blade up

to 3.4 cm. long and 4.5 mm. wide, the mid-nerve prominent beneath. Inflorescences axillary, fascicled, one or two flowers appearing at a time. Flower membranaceous. Sepals 3-nerved. Lateral sepals free, lanceolate to ovatelanceolate, 3.5-4.5 mm. long, 1.2-2 mm. wide, obtuse acute or acuminate, somewhat asymmetric. Dorsal sepal very similar, concave. Petals lanceolate or ovate-lanceolate, about 3-3.5 mm. long, 1-1.5 mm. wide, acuminate, 1-nerved with a short supplementary nerve on each side at the base, more or less asymmetric. Lip ovate-elliptic in outline, 3-lobed near the middle, about 2 mm. long and 1.8 mm. wide across the lateral lobes; lateral lobes small, rounded-auriculiform; middle lobe much larger, ovate, acute, erose-dentate or denticulate near the apex; disc 3-nerved, bicarinate with the keels extending from the middle of the lateral lobes almost to the middle of the mid-lobe. Column arcuate-cylindric, dilated at the base, about 1.4 mm. long on the posterior surface, extended into a prominent foot. Pollinia complanate-pyriform.

The specimen from Arakaka (im Thurn s.n.) shows two stems about 5-5.5 cm. high of which one is distinctly 4-jointed. The column of the single flower present is about 1.1 mm. long, measured on the dorsal surface.

Octomeria parvula is vegetatively similar to O.parvifolia Rolfe, but differs markedly in flower structure.

BRITISH GUIANA, Essequibo River, Moraballi Creek, near Bartica. Nearly at sea-level. "Epiphyte. Fl. wholly lemon-yellow (including stele and labellum)." September 11, 1929. N. Y. Sandwith 234a (TYPE in Herb. Kew.): Arakaka. February 1896. E.F. im Thurn s.n. (Herb. Kew. on sheet with Octomeria integrilabia C. Schweinf.)

CORRECTIONS

On page five of Number 1 (1932) of the Botanical Museum Leaflets, a supposedly new combination Dipteryx panamensis was made. Recently it has been learned that this combination was made by Record and Mell in 1924. The correct citation should read Dipteryx panamensis (Pittier) Record & Mell Timbers Trop. Am. (1924) 303.

Furthermore, in a recent number (Bot. Mus. Leafl. 3 (1935) 39), an error in citation was made. Line 21 should read Pleurothallis biflora Schlechter in Fedde Repert. Beihefte 19 (1923) 181.

THROUGHOUT our studies of North American Epidendrum, one group of species has been a constant source of perplexity. In part this perplexity has arisen from an inadequate knowledge of the types, and in still greater measure from the variability and close affinity of the species. The first difficulty (inadequate knowledge of the types) has been removed by the receipt of flowers from the types of Epidendrum oncidioides Lindl., E.graniticum Lindl., E.gravidum Lindl., E. Mooreanum Rolfe and E.profusum Rolfe, for which we have to thank Sir Arthur W. Hill, Director of the Royal Botanic Gardens, Kew, and of a flower from the type of E. guatemalense Klotzsch which was kindly sent to us by Dr. Rudolf Mansfeld of the Botanisches Museum, Berlin-Dahlem. The second source of confusion (variability and close affinity of the species) has been gradually eliminated by the receipt of more material, among which were certain linking forms, and by a critical study of the various elements. These comparisons and the true interpretation of formerly uncertain types have led us to believe that here again we are dealing, not with several distinct species, but with an alliance composed of varying forms of a single poly

morphic species.

EPIDENDRUM ONCIDIOIDES ALLIANCE

The constituents of this alliance present several marked lines of variation: in the stature of plant, in the character of inflorescence, in verrucosity of the ovary, and in the presence or absence of auriculate emergences of the column. The extremes of these variations would seem to indicate good species and have been so recognized, but the presence of intergrades and specimens showing a combination of characters point to one variable species. The trends of variation or the linkage of characters, however, render recognizable a typical form and five varieties.

The typical form of Epidendrum oncidioides as described and figured by Lindley from a plant sent to him by Richard Harrison, probably from South America, is a tall plant with a panicle about three feet long. The pseudobulb is ellipsoid and bears three ensiform leaves nearly two feet long and two inches wide. The inflorescence is an open panicle with the widely divaricate branches distant and not very long. The flowers are shown as being about three centimeters in diameter. The sepals and petals are dull chrome yellow, heavily blotched toward their apex with a dull red-brown and are greenish yellow on their exterior surface. The lip is a dull chrome yellow with short brown-purple lines on the mid-lobe. The sepals are shown as cuneate-oblanceolate with obtuse tips. The petals are round-spatulate with a narrow claw and are inrolled on the apical margin. The lip is distinctly 3-lobed with a well-marked isthmus, with the lateral lobes erect, clasping the column and oblong, their apices rounded and the mid-lobe is suborbicular and cuspidate (due to the inrolling of the apical margins).

The following synopsis sets forth briefly the characters of the concepts that have formerly been considered