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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 8, No. 3 



Between altitudes of about 4,000 and 3,500 feet on the slopes was a great deal of 

 bamboo (Oxytenanthera abyssinica), averaging about 30 feet in height, which 

 seemed to have come in after the destruction of the original vegetation. 



A patch of tall rain forest, perhaps a square mile in area, occupied the east- 

 ern slopes of Nchisi Mountain from about the 5,000-foot level to the crest of 

 the summit ridge. Elsewhere on the relatively moist eastern slopes, and cover- 

 ing all the drier western side of the mountain except for one rain-forested gully, 

 were Brachystegia woodlands. In earlier times, when raiding Angoni impis struck 

 into this area, the local Chewa people took refuge on the mountain. Taking their 

 cattle with them, they fled into the rain forest, where, for fear of evil spirits, the 

 Angoni would not follow them. The word nchisi is said to mean fortress in the 

 Chewa language. 



In the rain forest of the mountain several species of trees including, among 

 those collected, Cbrysopbyllum fulvum S. Moore, Pygeum africanum Hook, f., Lacb- 

 nopylis viscosa (Gibbs) C. A. Sm., Syzygium guineense (Willd.) DC, and 

 Rauvolfia caffra Sond., attained large size. Magnificent trees of Piptadenia 

 buchananii Bak., well over 100 feet tall and with boles at least six feet in 

 diameter, dominated the forest locally. But in all its strata, from canopy layer 

 to floor plants, the forest was poor in species. There were no enriching palms or 

 tree-ferns, few lianas, and only a sparse epiphytic flora of mosses and such ferns 

 as Asplenium sandersonii Hook, and A. mannii Hook. Under a predominantly 

 woody undergrowth, usually tall and easy to walk through, Oplismenus compositus 

 (L.) Beauv. and the ferns Tectaria gemmifera (Fee) Alston and Pteris quadriaurita 

 Retz were fairly common ground plants. In moist gullies Rhinacantbus nasutus 

 (L.) Kurz and other Acanthaceae occurred with a richer and more abundant repre- 

 sentation of ferns including Dryopteris spp., Asplenium inaequilaterale Willd., 

 Didymocblaena truncatula (Desv.) C. Chr. , and large Marattia salicifolia Schrad. 



Protection to the edges of the rain forest from dry-season fires burning in 

 adjoining woodlands was provided by an ecotone of sappy shrubs and tall herbs 

 generally some yards in width, and in only one place was this seen to have 

 been ineffective to the extent that a fire had burned to the edge of the forest 

 proper and done some damage by scorching marginal small trees. Many constituents 

 of the border community such as Dombeya aff. platypoda K. Schum., Iboza riparia 

 (Hochst.) N. E. Br. with showy white or lavender panicles, Abutilon longicuspe 

 Hochst., Hypoestes verticillaris (L. f.) R. Br., Ocimum suave Willd., and scram- 

 bling Cyatbula cylindrica Moq.were also met with in the edges of gallery strips of 

 rain forest in moist to half-swampy gullies in the dry Brachystegia woodlands. 

 Syzfgium cordatum Hochst. was the chief tree of these gallery forests, Anthocleista 

 zambesiaca Baker with pale leaves up to two feet long, the most striking. Most 

 unexpectedly, in the absence of tree-ferns from the main forest of the mountain, 

 stout-stemmed Cyathea 17102 was found in one of the wetter gallery forests. 



Brachystegia spiciformis Benth., the principal tree of the woodlands, had 

 crooked, lichenous, and often orchid-cluttered branches forming a flattish to 

 very flat crown. In hollows and gullies the tallest trees were about 40 feet high, 

 and Hyparrhenia gazensis (Rendle) Stapf and H. bracteata (Humb. et Bonpl.) 

 Stapf characterized a dense body of grass 3 to 9 feet tall. On the dry crests of 

 ridges the trees were so low that one had to stoop to see under them and over a 

 rather thin grass cover in which Themeda triandra Forsk. var. hispida Stapf sup- 

 plied most of the stocking. Associated trees included Faurea 17132, Monotes 

 africanus A. DC., and in local abundance Isoberlinia paniculata (Benth.) Hutch, 

 and Uapaca kirkiana Muell. Arg. Leguminous Droogmansia whytei Schindl., 

 Aeschynomene nyikensis Bak., and Eriosema affine De Wild, were common shrubs. 



