Root fibrous, annual? Leaves radical, erect, linear-lanceolate, rigid, minutely denticulate, having a her- baceous somewhat acid taste. Scape a foot or more in height, without leaves or scales, clothed with glandular hairs. Inflorescence a spiked raceme. Bractes three at the base of each pedicle longer than it: external lower one largest, oval- acuminate, with a round gland at its base; two internal ones shorter, linear. Calyx persistent, superior, bilabiate: lips divaricate, when the flower first opens apparently quite entire, but, after the blossom is fallen, the one evidently two- the other three-toothed. Limb of Corolla five-cleft, four of the laciniæ ovate, spreading, two upper ones some- what larger than the lower: the fifth (or labellum) smaller, linear, recurved, having two small, subulate, upright ap- pendices at its base: tube longer than calyx: faux beset with eight thread-like, glandular processes, erect, unequal. Column flattened-cylindrical sigmoid, bearing at its extremity two two-loved anthers with lobes extremely divaricate, and be- tween them the green stigma, more evident after the anthers have discharged their pollen; the margin of the receptacle of the anthers is surrounded by lucid hairs, when maginified resembling icicles. Germen after the fall of the corolla ovate, inflated, two-celled, cells parted by a very thin dissepiment: ovula many, attached to the centre of the dissepiment. There are several species of which possess a singular irritability of the column, and, perhaps, this property is in none more remarkable than in the present plant; in which the column is, in its natural state, bent over the re- flected labellum, so as to bring the capitulum, containing the anthers and stigma, nearly in contact with the germen; when slightly touched near the base, the column suddenly springs up, carrying the capitulum with a sudden jirk over to the opposite side of the flower. When left quiet, after a short time the column gradually resumes its former position, ready to spring again when exposed to any irritation, but probably with diminished force every time. That the real stigma is situate in the centre of the capi- tulum, terminating the column, is, we believe, now generally admitted, though for some time warmly disputed. The use of the above mechanism is not very evident; to us it appears most probable, that it is intended to disperse the pollen, to insure the fertilization of the ovary, which, notwithstanding the close approximation of the anthers and stigma, is, perhaps, impos- sible to be effected by its own individual anthers, from the stigma not being exposed till after the bursting of these. Our drawing was made from a plant kindly communicated by Mr. , of the Hammersmith Nursery, in December last, at which time they were generally in blossom, though not forced by artificial heat, but merely protected from frost.
Education Digest
Curtis's Botanical Magazine/Volume 44/1918
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