BIBLIOGRAPHY

De Candolle, A. (1833). In Guillemin, A., Arch. Bot. 2: 518. Halliday, P. (1984). The genus Kleinia (Compositae) in Arabia. Kew Bull.

( 1985). A new species of Kleinia from Arabia. Brit. Cact. Succ. J . 3:

(1988). Kleinia saginata in Hooker‘s Icon. PI. 39(4): 52-54, t.3884. Jeffrey, C. (1986). The Senecioneae in East Tropical Africa. Notes of

Trager, J.M. (1985). Cacti and succulents for the amateur. Senecio fulleri

39: 81 7-827.

36-37.

Compositae: IV. Kew Bull. 41: 873-943.

nom. nud. Cact. Succ. 3. (U.S.) 57: 1 13.

135. PHRAGMIPEDIUM BESSEAE Orchidaceae

Sarah Robbins

In 1981 Dr Calaway Dodson and Janet Kuhn described a new species of Phragmipedium in the American Orchid Society Bulletin. It was surprising that this species had remained undiscovered for so long, despite years of keen exploration by slipper orchid enthusiasts. Even more surprising was that it turned out to be one of the most spectacular members of the genus. The flower is attractively shaped, but it is the colouring that makes P. besseae such an exciting dis- covery. For years orchid growers had longed for a red slipper orchid; P. besseae is a stunning orange-red.

This beautiful orchid is named after Mrs Libby Besse who dis- covered it while on an expedition to northern Peru in 1981. Mrs Besse is a member of the board of the Marie Selby Botanical Gardens in Florida, and has contributed substantially to botanical exploration in the neotropics. On her return from Peru she took some live material of P. besseae to Dr Dodson, at that time Director of Selby, who confirmed that it was a new species.

Sometime later Selby held its annual orchid auction, and three plants of P. besseae from Mrs Besse’s original collection were made available. The plants were sold for an incredible US$1,700 each. Unfortunately all three plants subsequently died in cultivation.

Mrs Besse’s collection was not the first time that the species had been gathered from the wild. Werner Hopp had collected a specimen of P. besseae over 60 years earlier, but Rudolf Schlechter had mis-

156

Plate 135

Phragmipedium besseac STIG DALSTROM

identified it. In Schlechter’s 1924 discussion of Hopp’s Colombian collections in Beitrage zur Orchideenkunde uon Colombia, he suggested that Hopp’s colour notation was in error. One of the two specimens named as P . schlimii (Reichb. fil.) Rolfe was described in Hopp’s field notes as yellow-brown, and the second was described as rose-red. Schlechter assumed that Hopp had been careless, but it now seems likely that the rose-red specimen was P . besseae. Phragmipedium schlimii, although similar to P . besseae, differs mainly in having a smaller pink flower, and narrower leaves. Both of Hopp’s specimens were sub- sequently destroyed when the Berlin herbarium was bombed during World War 11.

The reason that P . besseae remained unknown for so long is probably due to the fact that it occurs on sheer rock faces at elevations between 1,300m and 1,500m. Such places tend to be avoided by road and trail builders, thus remaining isolated and unexplored. One colony in Ecuador was found because it was growing beside a newly constructed access road to a dam.

Unfortunately, because P . besseae is such a valuable and horti- culturally desirable plant, it has already suffered from commercial exploitation. Soon after the original description was published, orchid collectors descended upon northern Peru. It is interesting to note that in the description, details of the locality were incorrect, and many collectors spent weeks searching in the wrong place. Usually as soon as a colony is discovered it is destroyed. One scientist who had been searching for the species in Ecuador for a year and a half, eventually found a colony. He ran back to the truck carrying a plant. The driver asked what all the excitement was about and the scientist made the mistake of telling him. The next day the driver was back with collectors who removed hundreds of plants; sadly as P . besseae is relatively hard to grow, most of these plants probably died.

CULTIVATION. Phragmipedium besseae grows in a different manner to other species of Phragmipedium. In the wild it forms dense clumps with runners, rather like those of strawberries, between the plants. For this reason small cuttings of the plant tend to shrivel, as they cannot take up enough water. I t is therefore best to grow a clump of plants in one bed, instead of having the growths individually potted. The usual Phragmipedium compost of leaf-mould is not very suitable and P . besseae can be grown more successfully in sand, better still in pumice gravel. At the Marie Selby Botanical Garden P . besseae grows well in gravel covered with epiphytic moss. The plants are fed with

157

horse manure which has been steeped in water for about six weeks. At Kew P. besseae is grown in a glasshouse, in light shade, at a minimum temperature of 17°C and a maximum of 30°C. Plants with no roots are placed in a fine grade mix of tree-fibre and moss and moved to a medium mix when the roots have established. The humidity is kept high, 90 per cent at night and 70 per cent during the day. Phragmipedium besseae has not yet flowered at Kew.

Phragm$edium besseae has been hybridized with Phragmipedium ‘Red Gem’, (a cross between P. longiflium (Reichb. fil. & Warsc.) Rolfe and P. schlimii). This hybrid has now been crossed with P. schlimii three times. The result is almost identical to P. schlimii in shape but has the red colour of P. besseae. Soon a red hybrid slipper orchid that is easy to grow should become available commercially. This is an exciting prospect and should help to save P. besseae from being further stripped from the wild and possible extinction.

DESCRIPTION. A lithophytic or terrestrial herb. Leaves 6- 10, narrowly elliptic, up to 7cm long, 1-2cm wide, spreading, glabrous. Injorescence erect, produced from the apex of the stem, l-4-flowered; flowers produced in succession. Peduncle terete, shortly pubescent, sometimes with a vaginate, ovate sheath below the middle. Floral bracts erect, navicular, compressed, up

PBragmipedium besseae. A, dorsal sepal, x 2; B, petal, x 2; C, synsepalum, x 2; D, lip, longitudinal section, x 2; E, column with staminode, side view, x 4; F, column with staminode, front view, x 4; G, staminode from below, x 4. Drawn by Sarah Robbins.

158

to 2.8 cm long. Flower orange-red, c. 6 cm across. Pedicel and ovary cylindrical, up to 7 cm long, densely pubescent. Dorsal sepal orange-red, pale apricot on reverse, ovate, obtuse, slightly concave, sparsely pubescent, up to 2.7 cm long and 1.6 cm wide, united to the lateral sepals at the base. Lateral sepals orange-red, apricot on reverse, connate to near the apex, concave, broadly elliptical, 2-2.7 cm long, 1.5-2 cm wide, sparsely pubescent, emarginate at the apex. Petals orange-red, obliquely ovate, flat, erect, c. 2.9 cm long and 1.8 cm wide, obtuse, slightly cordate at the base, sparsely pubescent. Lip pale orange with translucent segments on each side, up to 2.3 cm long and 1.6 cm wide, calceolate, ovoid, inflated, margins involute forming a quad- rate opening 3 mm in diameter. Column short, pubescent; staminode obovate-subpentagonal, emarginate at apex, sparsely pubescent.

DISTRIBUTION. Peru, Ecuador, Colombia; altitude 1,100- 1,500 m.

Phragmipedium besseae Dodson & Kuhn in Amer. Orchid SOC. Bull. 50: 1308 (1981). Type: Peru, San Martin, on the road from Tarapoto to Yurimaguas, lithophytic on wet granite rocks in semishade, alt, 1,100 m, 13 JuIy 198 1,3. ffalton t3’ E. Besse 62 (holotype SEL) .

136. SKIMMIA x CONFUSA ‘Chelsea Physic’ Rutaceae

Nigel P. Taylor

The hybrid figured here was first named just two years ago, in a revision of the genus Skimmia published in this Magazine; however, its origin probably dates from at least thirty years earlier (Taylor, 1987). Skimmia x confusa N.P. Taylor (S.japonica Thunb. subsp.

japonica x S. anquetilia N.P. Taylor & Airy Shaw), which has not been illustrated in colour before, rivals the common S.japonica as the most garden-worthy member of its genus.

The form depicted was found in a corner of the Chelsea Physic Garden, London, and is here given the clonal name ‘Chelsea Physic’. I t is a selection from amongst male clones of the hybrid, including that identified as ‘Kew Green’ (Brown, 1980), from which it differs in its lower, more spreading habit, generally narrower leaves and smaller inflorescences. I t may prove to be a more valuable plant than ‘Kew Green’ in that it is of dwarfer habit and thus more suitable for small gardens. Grown in a border, away from direct sun for most of the day, it produces healthy, dark green, pleasantly aromatic foliage and is most attactive in spring, after flowering, when the dark mature

159