Xll PREFACE, 



Lieutenant C. S. Smith. Plants from Umba Valley, German 

 East Africa, collected during the Anglo-German Delimitation 

 Commission. (Kew Bulletin, 1893, p. 146.) 



Joseph Thomson. Collections from the neighbourhood of 

 Lakes Nyasa and Tanganyika. (See Journal Linnean Society, 

 Botany, vol. xxi. pp. 392-406. Died 1895.) 



Alexander Whyte. An important collection from Nyasa- 

 land. (See Kew Bulletin, 1897, pp. 241, 243-300 ; 1898, pp. 145- 

 164.) 



As soon as I was able to organise the necessary staff* the work was 

 attacked at various points. But some time necessarily elapsed before 

 sufficient material was accumulated to commence printing. When a 

 work of this kind is once planned out, it is immaterial what part is 

 first issued. I eventually decided to first issue the present volume 

 (the seventh), devoted to the Petaloid Monocotyledons, as these groups 

 of plants are of wider general interest. The printing of the volume 

 commenced in July of last year, and has been attended with very 

 considerable difficulties. Whether it is followed by any other 

 volumes will largely depend on the extent to which these difficulties 

 are removed. 



I have to express my obligations for the sympathetic assistance 1 

 have received from the following foreign botanists: — 



Mons. W. Barbey, Herbier Boissier, Geneva. 



Professor Bureau, Jardin des Plantes, Paris, who has 

 obligingly lent the specimens of Liliacece from the French Congo 

 described by Mons. Henri Hua. 



Professor A. Engler, Director of the Royal Botanical Garden and 

 Museums, Berlin, who has communicated important collections made 

 by German travellers as well as numerous publications. 



Professor Th. M. Fries, Director of the Botanic Gardens, TJpsala,. 

 for the loan of the types of Swartz's orchids. 



Dr. Hans Schinz, Professor of Botany, Zurich. 



I have further to record my acknowledgements of the assistance 

 given me by Mr. C. H. Wright in preparing the manuscript for the 

 press and in checking the proofs, and to Mr. N. E. Brown for working 

 out the geographical distribution. 



For the detailed topography the third edition of the " Spezialkarte 

 von Afrika," Gotha : Justus Perthes, 1893, has been chiefly used. 



W. T. T. D. 

 Kew, Aug. 1898. 



