- (1984). Cornus in Manual of Cultiuated Broad-Leaved Trees and Shrubs 1 :

Macdonald, B . (1984). Two noteworthy Cornus introductions. The Garden

Shaw, R. (1972).APlantAssociationatKew.J. Roy. Hort.Soc.97: 30-31,fig.

Stapf, 0. (1910). Cornus nuttallii. Curtis’s Bot. Mag. 136: t . 831 1 . Synge, P. M. (1970). Tour to Dorset and Devon, 4th-11 th May 1970. In!.

366-372. B. T. Batsford, London.

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Dendrol. SOC. Yearbook 60-70.

SOME UNUSUAL ORCHID DISTRIBUTIONS IN MALAWI

Isobyl F. La Croix

Plant distributions can be strange; not infrequently a species is pres- ent in a very limited area, yet absent from other apparently similar areas. We came across several odd examples in northern Malawi.

The Research Station near Mzuzu in the Northern Region of Malawi where we lived from 1985 to 1987 was situated on what had once been a Commonwealth Development Corporation tung estate. About 15 years ago, the market for tung oil slumped and the estate was given up; some of it was taken over by the Ministry of Agriculture. Most of the tung trees (Aleurites spp.) were removed although some remained and these seeded themselves fairly freely. Much of the Research Station’s land was used as cattle pasture, rough grassland with scattered trees, but there were quite large areas of secondary woodland with species of Brachystegia and Uapaca predominating, and at the southern end, fortunately near our house, a network of streams ran, still with a good fringe of riverine forest.

In Malawi, no woodland or forest is without paths - for wood- gathering, poaching or just for getting from A to B - so every morning I combined exercising the dog with plant-hunting, bird- watching and general exploring.

Large mammals in the area were few; so close to a town (Malawi’s ‘Third City’ in fact) most had been hunted out. There was a large troup of green vervet monkeys which raided gardens, a few hardy survivors of bushbuck, some small cats, probably serval, and on one memorable occasion a group oflions passed through, eating a cow en route. The bird life was interesting with many raptors and several uncommon species such as Guning’s akalat and the green-headed sunbird and spectacular ones like the nerina trogon.

While Brachystegial Uapaca woodland is widespread in the north and is often rich in epiphytic orchids, this woodland had few

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epiphytes and not a great variety of terrestrial orchids, presumably because it was secondary and too young. The riverine forest, however, was original and yielded two new generic records for Malawi, one terrestrial and one epiphytic.

I found the terrestrial orchid one morning when I followed the dog who had plunged along a narrow, overgrown path. Towards the top of a bank above the stream, in heavy shade and rooting in leaf-litter, was a colony oforchids in early bud - this was in July, in the first half

A, Taeniophyllum coxii; B, Platylepisglandulosa; C , Zeuxinc ballii. Drawn by Isobyl F. La Croix.

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ofthe dry season. The plants had no tubers but creepingstems rooting at the nodes and appeared to be a species of Zeuxine, Cheirostylis or Hetaeria. They formed almost the sole vegetation in an area ofperhaps 10 square metres, and knowing how easy it could be not to be able to re-find such a colony, I collected two or three plants and grew them on in a pot to await flowering. This they duly did, in mid-September, late on in the dry season, and proved to be Zeuxine ballii Cribb, first described in 1977 and previously known only from eastern Zimbab- we. The plants were photographed in flower and specimens pressed, and we decided to return to the colony and photograph them in situ. We went to what I was sure was the right place but no plants could be seen. Although the stream still flowed, the bank was by now very dry.

The following year I returned to the bank in July and there the plants were, once more in bud. A few months later they had again disappeared without ever having flowered. In both years the rains had been poor and finished early; possibly in a year when rain was plentiful and prolonged they would continue to grow, flower and set seed, but it did seem to be a species almost trying for extinction.

The day after I had first found the colony, we were in another part of the forest, in a swampy area just below the house, and found another colony oforchids with creeping stems which looked different from the first. These behaved in a more normal way and flowered in the wild in January, turning out to be Platylepisglandulosa (Lindl.) Reichb. fil., a species widely distributed in tropical Africa but in Malawi known previously from only one locality in the south. In spite of prolonged searching, I never found either of these species in any other part of the forest network.

The other new generic record was also fortuitous. I was looking with binoculars at a large epiphyte at the edge of the riverine fringe when I saw what I thought was a small Microcoelia. Again, plants were not infrequent in a small area growing on twigs and small branches of Syz-ygium cordatum, on thicket-forming shrubs and on lianas. I kept an eye on the colony and when the plants flowered in July, they turned out to be not a Microcoelia but Taeniophyllum coxii (Summerh.) Sum- merh., the sole known African representative of an Asiatic genus, known only from one site in Ghana, two in Zaire and one in eastern Zimbabwe. However, as the plants are leafless, with a diameter across the roots of about 5 cm and the flowers are minute, pale yellow and open one at a time, it is a species not hard to overlook. Not long before we left MZUZU, we found that someone had been cutting the thicket to cover a charcoal heap-in fact we rescued a number ofplants from the

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potential pyre. Charcoal-burning was illegal as the area was protec- ted by the Forestry Department, but although the rangers arrested charcoal-burners and other illegal fellers when they could catch them, the fines were derisory and it paid those involved just to carry on and hope that they would not be caught too often.

These were not the only species ofinterest in that area and we hope that it will be incorporated into a proposed Botanical Garden for the Northern Region; nothing else is likely to safeguard it, as with the rapidly increasing population of the Mzuzu area, illegal felling is also increasing fast.

Another similar patch of riverine forest on a cattle ranch about three miles away yielded a further new generic record for Malawi. This was of Ancistrorhynchus tenuicaulis Summerh., although the first plant we found was sterile, another was obligingly in flower. Ancistro- rhynchus Finet is a genus of about 13 species ofepiphytic orchids found from West to East Africa and this was the most southerly occurrence so far recorded.

Close by, in a Forest Reserve and beside an army firing range (and where the army tended to gather some of their fuel supplies) we found a new species ofPolystachya, again in a small area that seemed to differ in no way from other parts ofwhat was an extensive tract ofwoodland.

Many other species ofplant must occur in similar small, unremark- able areas and if population increase and habitat encroachment continue, how many will disappear before they are ever found? Everyone is now aware of the destruction of tropical forest in all continents where it occurs; publicity is given to the clearing of vast areas by timber companies and cattle ranchers. Although it may have little effect on world climate, small scale destruction is also important; one man and an axe can fell many trees in a short time, and a small and fragile habitat is gone for ever.

THE WAXING OF A GLORIOUS RAJAH

E. Charles Nelson

In the museum collections ofthe Royal Botanic Gardens, Kew, there is a glorious rajah - and an Irish one to boot! - resplendent in green and scarlet. Its original caused exclamations ofwonder, and provoked from a Kew curator a whoop of‘Bravo!’, followed by aplea to ‘give us a chance’, when he glimpsed it.

This is the tale of the rajah’s arrival in Kew, and ofits waxing, with some miscellaneous excursions hither and yon.

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