Sepals obovate, silky. Corolla much longer than the sepals, sometimes twice as long. Ripe capsules about equalling the calyx.—D. repens var. brevifolia, Kirk in Trans. N.Z. Inst. x. app. xxxvii.
North and South Islands, Stewart Island: Not uncommon throughout, ascending to 3000 ft. November–January.
I retain this as a species with considerable hesitation, but it appears to constantly differ from reduced states of D. repens, which it otherwise much resembles, in the larger flowers with the corolla always much longer than the calyx.
5. CUSCUTA, Linn.
Leafless usually annual herbs, germinating in the soil but not rooting in it, producing filiform branched stems which twine round herbs or shrubs and become parasitic by means of suckers which penetrate the bark, the lower portion of the stem then dying away. Flowers small, usually whitish, in dense or open cymose fascicles, sessile or shortly pedicelled. Sepals 5 or 4, distinct or connate at the base. Corolla campanulate or urceolate or ovoid; lobes 5–4, short, imbricate in the bud. Stamens 5–4, inserted on the throat of the corolla, above a ring of many scale-like lacerate appendages. Ovary globose, 2-celled, 4-ovuled; styles 1 or 2, persistent; stigmas capitate or filiform. Capsule 1–4-seeded, membranous, dry or succulent, circumscissile or bursting irregularly. Seeds glabrous, albuminous; embryo long and slender, spirally coiled; cotyledons wanting or obscure.
A very remarkable genus, comprising about 90 species, spread through most tropical and temperate countries. Some of them, such as the clover dodder, C. epithymum var. trifolii, are dangerous pests to cultivated crops. The single New Zealand species is very imperfectly known, and may not be truly indigenous.
1. C. densiflora, Hook. f. Fl. Nov. Zel. i. 186.—Stems slender, densely matted and twisting together, as thick as stout thread. Flowers crowded in short densely congested 6–10-flowered racemes ¼–½ in. long. Calyx shortly 5-lobed; lobes oblong, obtuse. Corolla ⅛ in. long, subcampanulate, marked with transparent oil-glands; lobes 5, short, rounded, recurved. Scales broadly oblong, obtuse, fimbriated, united at their bases by a thin membrane. Filaments longer than the anthers. Styles 2, rather long; stigmas capitate.—Handb. N.Z. Fl. 199.
South Island: Marlborough—Port Underwood, Lyall.
I have seen no specimens of this, and the above diagnosis has been drawn up from those given by Hooker in the Flora and the Handbook. According to Hooker, Dr. Engelmann, who examined the type at Kew, reported that it hardly differs from the South American C. racemosa, Martius, a species which was introduced into Europe many years ago, and caused much damage to crops of lucerne. It subsequently appeared in fields of lucerne in California. Mr. Kirk (Trans. N.Z. Inst. xx. 182) records the occurrence of the same plant (under the synonym of C. hassiaca, Pfeiff.) in lucerne-fields in Canterbury, but there are no specimens in his herbarium.
