xii 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 I 
have received from the following foreign botanists :— 
Mons. W. Barbey, Herbier Boissier, Geneva. 
Professor Bureau, Jardin des Plantes, Paris, who bas 
obligingly lent the specimens of Liliacee 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, Upsala, 
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. E I D: 
Kew, Aug. 1898. 
