196 WEST AFRICAN FORESTS AND FORESTRY 
Stylochiton Dalzielit, Amorphophallus Barteri and A. dracontiowdes, 
Anchomanes Dalzielti, and other species. 
CyPERACEs by very numerous species of Cyperus, e.g. the edible 
Aya, C. esculentus, and the uncultivated Aya aya, C. rotundus, C. 
Fenzelianus, etc., and several of Pycreus, Fimbristylis, Kyllingia, 
Bulbostylis, etc. 
GRAMINEZ by the predominant tribe, Andropogonee, with numerous 
other genera—Eragrostis, Aristida, Digitaria, Pennisetum, Chloris, etc., 
and by a single locally distributed bamboo, Oxytenanthera Abyssinica. 
The chief cereal is Guinea Corn, Dawa, Sorghum vulgare; both 
species of sugar-cane, Rake, Saccharum officinarum, and Takanda, 
Sorghum vulgare, var. saccharantum, are cultivated. 
The Fiices are poorly represented by the widely distributed 
Adder’s Tongue, Ophioglossum vulgatum, the water-fern, Cratopteris 
Thalictroides, by Adiantum lunulatum, A. Schweinfurthii, and a few 
species of Nephrodium asplenium, etc., by no means typical of the 
region. 
Having thus given a bird’s-eye view of the floral composition in 
the central region of Hausaland, one may proceed to examine the 
variations revealed in passing south to the semi-evergreen forests 
and north to the drier open savannahs. 
Southwards the transition is gradual, and nowhere abrupt, from 
forest savannah with annual bush-fires and consequent tendency to 
revert to grass, to forests in which the number of species is greater and 
the deciduous element is more mingled with evergreens, either by the 
persistence of species which in a drier region are deciduous, but retain 
their foliage where the increased rainfall allows of this variation, or 
by the appearance of species which always possess the evergreen habit. 
Bombax buonopozense is an example of the former and probably also 
Afzelia Africana and several others. 
Some of the added constituents either absent from or more rare 
in the area of lesser rainfall are : 
Anonackz#z: Xylopia parviflora, Hexalobus Senegalensis, Popowia 
Mannii. 
CaPPaRIDACEZ: Ritchiea sp., Capparis viminea, etc. 
Brxrnzaz: Oncoba spinosa. 
StercuLiacex: Cola laurifolia. 
Ruraorz: the Fasa kwari, Zanthozylum Senegalense. 
Metiacez: Trichilia retusa. 
AnacaRDIacEz: Spondias lutea, Haematostaphis Barteri, and the 
cultivated mango. 
Sarinpacez: Blighia sapida. 
ConNARACEZ;: scrambling shrubs, e.g. species of Agelea and 
Cnestic. 
