OROBANCHE RUBRA. RÉD OR BASALTIC BROOM-
RAPE.
OROBANCHE rubra ; caule simplici, corolla tubulosa, labio superiore bilobo, inferiore trilobo, lobis
obtusis asqualibus, staminibus hinc glanduloso-pilosis, bracteis solitariis.
OROBANCHE rubra. Smith E ngl. Bot. 1 .1787. Compend. El. B r it. ed. 3. p. 95.
Class a n d Order. D ID Y N AM IA ANGIOSPERMIA.
[N atural Order. RH INANTHACEÆ, Div. I I. OROBANCHEA, Capsula monolocularis, bivalvis;
valvulis liberis in nervo longitudinali seminiferis. D e Gand. PEDICULARES, Juss.]
Ge n . Char. Calyx e foliolis duobus, lobatis, lateralibus. Corolla ringens. Capsula unilocularis, bivalvis, po-
, lysperma. Glandula sub basi germinis. Sm.
Gen. Char. Calyx composed of two lobate, lateral leaves. Corolla ringent. Capsule dne-celled, bivalved, many-
seeded. Glands under the base of the germen. Sm.
Radix fibrosa, fibris sublignosis, flexuosis, fuscis.
Tota Herba, bracteis exceptis, coccinea, in floribus
purpureo-tincta.
Caulis palmaris ad spithamseam et ultra, erectus, simplex,
subteres, basi incrassatus, subbulbosus, su-
perne sensim attenuatus, glanduloso-hirsutus, vi-
scidus, squamosus; squamis inferne minoribus,
numerosis, imbricatis, superne distantibus, omnibus
fusco-coccineis, ovati’s, acuminatis, subgla-
bris.
Flores in spicam oblongam terminalem, circiter viginti,
odorati.
Bracte2E solitarise, squamas caulinas simulantes.
Calyx e foliolis duobus, bractea minoribus, laneeolatis.
Corolla unciam longa, tubulosa, ventricosa, leviter
curvata, basi angustata, longitudinaliter venosa,
extus glanduloso-hirsuta, bilabiata, labio superiore
bilobo, lobis brevibus, crenulatis, infiexis, lobulo
intermedio minuto, inferiore trilobo, lobis paten-
tibus, sequalibus, crenatis.
Stamina quatuor, didynamia, basi corollas inserta, corolla
breviora. Filamenta subulata, planiuscula,
basi apiceque glandulosa.
ANTHER2B bilobas, subtus .acuminatas, lobis superne de-
hiscentibus, glabris.
Pistillum staminum longitudine.
Germen anguste ovatum, glabrum, utrinque sulco longitudinali.
Stylus elongatus, attenuatus, substigmate curvatus,hinc
paululum glandulosus.
Stigma nutans, magnum, bi- vel tri-lobum, lobis rotun-
datis.
Pericardium : Capsula oblongo-ovata, stylo longo ter-
minata, sulcis sex longitudinalibus notata, longitudinaliter
dehiscens (bivalvis) unilocularis.
RECEPTACULA quatuor, parietalia, in singula valva duo,
longitudinalia, prominentia.
Root fibrous, fibres subligneous, flexuose, brown.
Whole Plant, bracteas excepted, of a purplish-red,
Semina minutissima, numerosa, subglobosa, fusca,
punctis profundis excavatis reticulata.
Albumen semini conforme, album, aquoso-camosum.
Embryo in parte inferiore albuminis, subglobosus. Co-
tyledones hemisphasricae. Radicula infera.
Fig. 1. Corolla. Fig. 2. the same laid open. Fig. 3.
dular hairs of the Corolla. Fig. 7. Capsule (nat. size).
show the receptacles. Fig. 10. Portion of a valve with
same divided vertically to show the albumen and embi
nified.
the flowers being most inclining to purple.
Stem from three inches to a span and upwards in height,
erect, simple, nearly round, thickened at the base,
somewhat bulbous, gradually becoming narrow
upwards, rough with glands, viscid, scaly, the
lower scales the smallest, numerous, imbricated,
the upper ones more scattered, all of a dark red,
ovate, acuminated, nearly smooth.
Flowers in an oblong, terminal spike, about twenty in
number, sweet-smelling.
Bracteas solitary, resembling the cauline scales.
Calyx of two leaves, smaller than the bractea, lanceolate.
Corolla an inch long, tubular, ventricose, slightly
curved, narrower at the base, longitudinally veined,
externally rough with glands, bilabiate, the
upper lip two-lobed, the lobes short, crenulated,
inflexed, the intermediate lobule very small; the
inferior lip three-lobed, the lobes patent, equal,
crenulated.
Stamens four, didynamous, inserted at the base of the
corolla, shorter than the corolla. Filaments subulate,
flatfish, glandulose at the base and apex.
Anthers bilobed, acuminated beneath the lobes, separating
above, smooth.
Pistil the same length as the stamens.
Germen narrowly ovate, smooth, longitudinally furrowed
on each side.
Style elongated, attenuated, curved beneath the stigma,
on one side slightly glandular.
Stigma drooping, large, two- or three-lobed, the lobes
round.
Pericarp ; Capsule oblongo-ovate, terminated by a long •
style, marked with- six longitudinal furrows, splitting
longitudinally (bivalved), one celled.
Receptacles four, parietal, two in each valve, longitudinal,
prominent.
Seeds very minute, numerous, nearly globular, brown,
reticulated with deeply indented points.
Albumen the same form as the seed: white, between
aqueous and fleshy.
Embryo situated in the lower part of the albumen. Cotyledons
hemispherical. Radicle inferior.
Stamen. Fig. 4. Pistil. Fig. 5. Stigma. Fig. 6. Glan-
Fig. 8. the same (magn.) Fig. 9• Capsule cut open to
the seeds on the receptacles. Fig. 11. Seed. Fig. 12. the
yo. Fig. 13. Embryo—all but Fig. 7. more or less mag-
I f it were not from a fear of subjecting myself to the imputation of making unnecessary changes in the nomenclature
of the plants that I describe, I should be very much disposed to alter the specific appellation of the one
now under consideration, to Orobanche basaltica, thereby conveying to the student who knows the plant only in
the herbarium, the information of its remarkable and peculiar choice of places of growth. As far as I have hitherto
had an opportunity of investigating the point, my researches have confirmed me in the idea, that the O. rubra confines
itself wholly to basaltic rocks, springing up in spots covered only with a very thin layer of soil, which to no
other plant, which with so little root has so large a stem, could possibly afford a sufficient portion of nourishment.
In such situations it was first discovered, in August 1805, by John Templeton, Esq. of Orange Grove, near Belfast,
on the Cave Hill, near that place. Mr. Dawson Turner and myself were so fortunate as to find it on the
island of Staffs, in 1809; and, since that time, Mr, Templeton has again met with it on the Giant’s Causeway,
where I gathered the specimens here delineated in July 1815, and was so happy as to be able to make the original
drawing on the spot. R. K. Greville, Esq. has lately informed me, that the O. rubi'a, still retaining its attachment
to basalt, grows on Salisbury Crags, near Edinburgh.
As to the generally received opinion of the parasitic nature of this plant, there was no appearance whatever of
its being so in the spots where I had the opportunity of examining it; most o f the specimens growing at a distance
from any other plant, and as it were insulated among the natural soil and fragments of the rock. Its colour
is most remarkable, and may serve at once to distinguish it from every known species of this difficult genus, as it
also leads to its being discovered in its native haunts with great ease by the eager botanist.
The whole plant is singularly glandular, and the calyx is composed of two undivided leaflets.
I t is extremely difficult to assign a sufficient reason for the predilection which the O. rubra appears to have for
basalt. Were it a plant, of which the long and strong roots were capable, not indeed of penetrating that substance,
which would be impossible, but of striking its fibres into the crevices of these rocks, it might be more easy to satisfy
ourselves on this point; or were the basalt a substance apt to break and chip into dust, and thus mingle with
the superjacent earth, we might conceive that peculiar plants might like that peculiar so il: but as the Orobanche
is a plant of but little root, and that o f but little strength; and as the surface o f basalt never crumbles, but is so
far from doing it that the turf may be peeled from off it, leaving exposed the rock, to which it does not at all appear
to have adhered, I feel quite a t a loss to explain what at present seems a very certain, though a mysterious
circumstance.
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