A large evergreen or semi-evergreen scrambling shrub, or a tall climber with a stout trunk, its branches armed with short, curved prickles. Leaves up to 8 in. long, dark green, they and the shoots reddish when young. Leaflets five or seven, of leathery texture, 2 to 4 in. long, elliptic or narrowly ovate, with slender acuminate tips (but more shortly acuminate on the flowering branchlets), rounded at the base, edged with numerous small teeth, glabrous on both sides except for occasional down on the midrib beneath, venation prominent on the undersurface. Stipules narrow, finely toothed at the edge. Flowers white, about 2 in. wide, up to fifteen or so in a lax panicle; flower-buds narrowly ovoid. Pedicels 1 in. or slightly more long, they and the receptacles glandular and often hairy, sometimes hairy and eglandular. Sepals hairy and glandular on the back, about 1 in. long, often slightly expanded at the apex, with a few lateral appendages. Petals densely silky on the back. Styles exserted, united into a hairy column. Fruits globular or broadly ellipsoid, up to 3⁄4 in. or slightly more long; sepals deciduous from the fully ripe fruit.
R. longicuspis was described in 1861 from a specimen collected by Hooker and Thomson in the Khasi Hills of Assam, and occurs in all the lower ranges of north-eastern India (including the outer Himalayas), probably extending into Burma and with close relatives in China. It is allied to R. brunonii, differing in the leathery, more acuminate leaflets almost glabrous beneath, fewer-flowered inflorescence, and the silkiness of the underside of the petals. But it is possible that intermediates occur in the eastern Himalaya.
There are no specimens in the Kew Herbarium of cultivated R. longicuspis, except for one from Headfort, Eire, apparently from a private introduction. But seeds were sent by Kingdon Ward from the Naga Hills of N.E. India under his KW 7740, collected in 1927, and plants may have been raised from these in private gardens. He may also have collected seed from the plants he found in the Assam Himalaya near Shergaon in 1935. A rose has been distributed as R. longicuspis, and is described and figured under that name in Graham Thomas, Climbing Roses, p. 35 and fig. 2. The author now accepts that it is not that species; as he remarks, it is near to R. mulliganii, for which see under R. rubus.
R. lucens Rolfe. – The type of this species was a plant at Kew received from Vilmorin, but raised from Wilson’s 1334 (not W. 1234 as stated in Rolfe’s description); the seed was collected in W. Szechwan, China, in 1908. It is certainly very near to R. longicuspis, as Rolfe admitted, and is included in it by Render. The chief difference, not noted by Rolfe, is that the petals are glabrous on the back. The leaflets are shorter than in R. longicuspis and more shortly acuminate, but there is little or no difference in the inflorescence, nor in the size or shape of the fruits, which in Wilson’s specimen 1334 are about as large as in R. longicuspis, though somewhat smaller on the cultivated plant that Rolfe took as the type of R. lucens. He also identified as R. lucens the plants raised from W. 4127, collected in W. Szechwan during Wilson’s second expedition for the Arnold Arboretum. These might still be found in private gardens, probably under the name R. longicuspis, since W. 4127 was referred to that species by Rehder and Wilson. For a rose distributed commercially as R. longicuspis see under R. mulliganii, p. 133.
R. sinowilsonii Hemsl. & Wils. – This species was discovered by Wilson on Mt Omei in W. Szechwan, China, in 1904 and introduced by him. It is very near to R. longicuspis, with the same large leaves richly coloured when young, and large flowers with silky-backed petals, but the pedicels, receptacles and sepals, though sometimes slightly glandular, are not or only slightly hairy, and the flower-buds, narrowly ovoid and tapered in R. longicuspis, are broadly ovoid in R. sinowilsonii.
At Kew, R. sinowilsonii grew for many years on the wall of the Herbaceous Ground. At Wakehurst Place in Sussex it has climbed 45 ft in a Chamaecyparis, and is also grown at Borde Hill in the same county. This species is really more remarkable for its fine foliage than for its flowers, which do not make much display. The leaves are sometimes 1 ft long.