Fterodiscics] xciii. pedaliace.e. 795 



than in other tropical countries ; but as they consist mostly of 

 herbs they do not greatly affect the physiognomy of the vegetation. 



The tribe Pedaliese has only one representative in the collection ^ 

 and of that one only a single specimen was found ; but it is very 

 probable that Uncaria ])roGumhens Burch., the grapple plants 

 occurs in the southern part of Mossamedes on the sandy Cunene 

 plains. 



The tribe Sesamese is most frequent about Benguella and in 

 the Mossamedes district. Two species of Sesamum, namely, 

 S. angolense and aS'. rigiclmn, have both opposite and alternate 

 leaves on one and the same specimen. The cultivation of S. 

 orientalej which is carried on with profitable results in India ^ 

 Egypt, Mozambique, etc., was started in Angola during the 

 time when Pedro Alexandripho do Conha was governor-general^ 

 and again at a later period before Welwitsch's time, though 

 always with but small success ; but the experiments appear not 

 to have been made in the parts of the province best adapted for 

 the purpose. The colonists complained that the exceedingly 

 irregular ripening of the seeds so reduced the crop that the 

 cultivation of this oil-plant had resulted in a loss; during the 

 latter part of his travels, however, Welwitsch saw in the interior ^ 

 chiefly on the high plateau east of Pungo Andongo, the plant 

 cultivated by the negroes, though only in small quantities and foi- 

 their own use, and he was firmly convinced that trials made by 

 experienced colonists and in properly chosen districts in the 

 highlands would lead to favourable results. The negroes of 

 Pungo Andongo cultivate it, not for the extraction of oil, but for 

 making cakes, which they bake with the crushed seeds, and which 

 they look upon as a delicacy. In Cazengo the cultivation had 

 been attempted and given up, as it was found that birds devoured 

 the seeds of the Sesamum before they ripened, and that Arach'is 

 hyjiogcea afforded a far more certain and profitable yield for the 

 production of oil. 



Several species possess roots containing a red dyeing material, 

 Avhich even in the herbarium stains paper, and they might 

 perhaps be used for dyeing purposes; this material is most 

 strongly developed in Sesamum triphyllum^ a species which i& 

 widely distributed from the banks of the Maiombo behind 

 Mossamedes up to the high plateau of Huilla. A mucilaginous 

 infusion is obtained from species found about Lopollo and Huilla. 

 >S'. 2)e7itaphyllitm with its large violet-purple flowers, and still moie 

 so the aS'. angolense of Pungo Andongo, are very ornamental plants,, 

 and probably might, at least in the warmer European countries, be 

 grown in the open air. 



1. PTERODISCUS Hook. ; Benth. k Hook. f. Gen. P]. ii. p. 1057, 

 1. P. aurantiacus Welw. in Trans. Linn. Soc. xxvii. p. 5S 



(1869); Schinz in Verb. Bot. Brandenb. xxx. p. 181 (23 June 1888). 

 Mossamedes. — A decumbent herb, glaucous-pruinose beneath : root 



thick, fusiform, almost napiform : stem prostrate, succulent, nearly 



