or THE NIGEE EXPEDITION. 181 



destroy sometimes the work of weeks : we have not on board a 

 tinned box, or indeed anything to make a water-tight case to put 

 dried plants in. 



In the lower parts of the river, till some distance beyond Abo, a 

 rich vegetation is prevalent : Oil and Wine Palms abound ; lofty 

 forest trees, for the most part unknown to me, grow together so 

 thickly at their summit, that the light is almost shut out below ; 

 trees overhanging the water were observed in this moist region co- 

 vered with Orchidece, principally of the genera Angrwcwm and Bol- 

 hopJiyllum ; Ferns, as epiphytes, are also abundant. JPlatycerium 

 Stemaria is on every tree. We however passed so quickly through 

 these parts, that I had few opportunities of landing, therefore did 

 little botanizing. Further up, where the country becomes pictu- 

 resque, with hills and low mountains, these extensive forests dis- 

 appear, and the air is drier ; the Wine Palm is replaced by the Fan 

 Palm ; Oil Palms are still abundant, but less luxuriant ; the huge 

 Bomhax With, its laminated trunk gives place to the unsightly Bao- 

 hob. The low mountains have all flat tops, seldom over 2000 feet 

 high, therefore yielding few novelties ; the sides of these are fre- 

 quently bare, composed of sandstone or coarse iron conglomerate. 

 The land from eighty miles below the confluence, to Rabba, w^here- 

 ever we have penetrated any distance, is of a sandy character mixed 

 with iron, therefore not fertile ; but it appears to be the true region 

 oiBassiaBarkii, or the Butter- tree, which occupies extensive tracts ; 

 it is a low scrubby tree, seldom more than 15 or 20 feet high, pro- 

 ducing its long leaves on the extremities of the branches : the quan- 

 tity of the butter offered us for sale would have filled a large ship. 

 On some mountains lately visited on the Kworra I have gathered 

 plants resembling the Cape vegetation, viz. Proteas, Aloes, Lo- 

 helias, BracJiysteJma, Ixias, Nycterinias, &c. I anticipate much 

 novelty should we reach any of greater elevation. A low belt of 

 ground always borders the river; in general this is swampy, 

 covered with tall grasses, among which a beautiful Gynerium is 

 now in flower ; it seems identical with the G. argenteum of our 

 gardens at home. 



To the Palms of Africa I have at least added four und escribed 

 species : one like Geonoma, the others Calami ; probably many of 

 the latter yet exist in the delta. I am not sure if the Fan Palm 

 is known by specimens : near the river it is scattered along singly, 

 generally at intervals one or two miles apart ; only once have we 

 seen them gregarious, on some mountains up the Kworra twelve 

 miles from the confluence : it does not form a large head j the leaf- 



