LISTERA CORDATA. HEART-LEAVED LISTERA.
LISTERA cordata ; caule bifolio, foliis cordatis oppositis, labello inferne bidentato, Iobis apicis lineari-
lanceolatis. Br.
LISTERA eordata. Brown in Hort. K m . cd. 2. vol. 4. p. 201. Hook. Fl. Scot. P . I . p . 253.
NEOTTIA cordata. Richard in Mém. du Mus. vol. 4. p. 59.
EPIPACTIS cordata. Swartz de Orchid, p. 66. TVilld. Sp. PI. vol. 4. p. 88. Decand. Fl. Fr.
ed. 3. vol. 3. p. 261. Fl. Gall. Syn. p. 172. P ers. Syn. PI. vol. 2. p. 513.
OPHRYS cordata. Linn. Sp. PL p. 1340. . Huds. Angl. p. 388. Lightf. Scot. p . 524. With.
Bot. Arr. cd. 4. vol. 2. p. 35. Hoffm. Germ. ed. 2. vol. 1. P . II. p . 178. Smith Fl.
Brit. p. 933. Engl. Bot. t. 358.
EPIPACTIS foliis binis cordatis, labello bifido postice bidentato. Hall. Helv. n. 1292. t. 22. ƒ 4.
BIFOLIUM minimum. The least Twayblade. Raii Syn. p. 385.
Class an d Ord er . GYNANDRIA MONANDRIA.
[Natural Ord e r . ORCHIDEAL, Juss., De ca n d ., Brow n , Hook.]
Gen. Char. Corolla irregularis. L a be llum bilobum. Columna aptera. A n th e r a basi inserta. Po llen fari-
naceum. B r .
Gen. Char. Corolla irregular. L ip two-lobed. Column wingless. A n th e r fixed by its base. Po llen farinaceous.
Radix e fibris plurimis horizontalibus, simplicibus,
crassiusculis (perennis ?).
Caulis palmaris vel subspithamæus, erectus, flexuosus,
striatus, ad basin squamis duabus vel tribus
oyatis, vaginatis, fuscis, munitus, medium versus
diphyllus.
Folia cordato-rotundata, opposita, acuta, glabra, longi-
tudinaliter venosa.
Flores viridi-fusci, in spicam laxarn dispositi, -breviter
pedunculati, bracteati, bracteis ovatis, minutis.
Perianthium sex-partitum, foliolis subpatentibus, tribus
exterioribus æqualibus, ovatis, concavis, viri-
dibus, trium interiorum duobus superioribus ob-
longis, fuscis, infimo, vel labello, fusco, lineari-
oblongo, pendente, basi bidentato, apice bifido,
laciniis lineari-lanceolatis, subdivergenti bus.
Columna perbrevis.
Anthera magna, stigmati parallela, viridi-fusca, dorso
convexa, facie plana, bilocularis, löculis longitu-
dinaliter dehiscentibus : Massæ pollinis ovato-
acuminatæ, compressæ, flavæ, farinaceæ.
Germen ovato-sphoericum, striatum, viridi-fuscum.
Stigma anticum, magnum, bilabiatum.
Capsula sphærica, unilocularis, sex-valvis, valvis alter-
nantibus viridibus, fuscisque, dorso obtuse cari-
Receptaculüm longitudinale in singulam valvulam.
Semina numerosissima, minutissima, oblonga, membra-
nacea, reticulata.
Root consisting of many horizontal, simple, thickish
fibres (perennial?).
Stem from three inches to nearly a span in height, erect,
fiexuose, striated, furnished at the base with two
or three brown, ovate, sheathing scales* bifoliate
at about the middle of its length.
Leaves between heart-shaped and round, opposite,
acute, glabrous, longitudinally veined.
Flowers of a greenish brown colour, arranged into a
lax spike, and borne upon short peduncles, brac-
teated, the bracteas ovate, minute.
P e r ia n t h of six subpatent leaflets, the three exterior
ones equal, ovate, concave, green, the two upper
ones of the three internal leaflets oblong, brown,
the lowest or labellum brown, linear-oblong, pendent,
notched at the base, bifid a t the point, the
segments between linear and lanceolate, slightly
diverging.
Column extremely short.
An t h e r large, parallel with the stigma, greenish brown,
convex behind, plane before, two-celled, the cells
splitting lengthwise: Pollen masses ovato-acu-
minate, compressed, yellow, mealy.
Ge rm en between ovate and spherical, striated, greenish
brown. .
St igma placed in front, large, two-lipped.
Capsule sphterical, one-celled, six-valved, the valves
alternately of a green and brown colour, obtusely
keeled at the back.
Receptacle longitudinal upon each vaive.
Seeds very numerous, very minute, oblong, membranaceous,
reticulated.
■ Flower. Fig. 2. The labellum. Fig. 3. Front view of the column of fructification. Fig. 4. Side view
of the same, showing the pollen masses which have fallen from the anther upon the back of the stigma. Fig. 5.
Pollen-masses. Fig. 6. Ripe capsule. Fig. 7. The same cut through transversely to show the situation of the
seeds. Fig. 8. Valve,of the capsule with its receptacle and a few seeds. Fist. 9. 9. Seeds.—all much masmi.-
The three British species of Orchidece which Mr. Brown includes in his get L is te ra , viz. L . N id u s A v is ,
L. ovata and L . cordata, have certainly many points in common in the general structure o f their flowers. The pre-
sent plant however, as does the Bird’s-Nest Listera, differs from the L . ovata most remarkably in the want of a
ngulate process at the back of the anther.
' flit®' alpine parts of Great Britain produce this plant in tolerable plenty: generally, however, the
in lviduals grow singly, and are a good deal concealed among grass or low shrubs; and for this reason, added to the
muteness of the stature and the inconspicuous hue of the flowers, the Heart-leaved Listera has been often over-
ooked, and considered more rare than it really is. It blossoms in the month of June.
old • T t sPec‘es are by Smith justly compared to those of Ophioglossum vu lg a tum and L u n a r ia botry-
■ i l an(1 tae same author suspects that they are truly perennial, not being merely a cluster of fibres for one year,
venr’ P® *?bdly obliterated (whilst a new cluster is forming) the next. A small bud or rudiment o f the future
) s stem °De is always seen nestled among the fibres, and this is analogous to one of the tubers of the O rch is genus,
and H'S °* t°e most d istinctly marked o f all our • Orchideous plants, an
and at once known by its diminutive size
tue two cordate leaves which it bears at about the middle of the stem.