VI 



particulars already given will prove adequate; but a list of 

 books and papers — in chronological order — of general interest 

 (Appendix I. p. 882) as foreshadowed on p. 12 has been extended 

 to cover the whole of West Africa, and, although every effort 

 has been made to include as many authors as possible, it is not 

 submitted as exhaustive. The important subjects of Mycology 

 and Entomology are reserved for other hands ; moreover, the 



m 



culture, during the last decade or so, afford ample ground for 

 abandoning the original intention to include at least some 

 details as to diseases of cultivated plants. 



Before dealing with the plants themselves it seemed desirable 

 to say something with regard to the Geography — physical and 

 political — of the area m which they occur and to deal briefly 

 with other cognate subjects bearing on the Botanical, Agricultural, 

 and Forestal develoj^ment of the country. 



I have to acknowledge most gratefully all the invaluable 

 assistance I have received from my colleagues at Kew — in the 

 Herbarium, the Museum and the Gardens. On no one of the 



many 



M.A., F.L.S., who has since left Kcav 

 ship of Botanv at the Universitv of A 



I am especially indebted for assistance at the time that most 

 difficult Order Leguminosae was in hand, in the course of which 

 he was responsible for several new species and, together with 

 Dr. Stapf, F.R.S., for the new genus Isoherlinia (see p. 266). 

 I am further indebted to Mr. I. H. Burldll, M.A., F.L,S., Director 

 of the Botanic Gardens, Singapore, for assistance with the 

 Dioscoreas (p. 089) and likemse to Mr. N. E. BroMTi, A.L.S., 

 who has since retired from the Kew Staff, for advice on certain 

 of the Asclepiads (p. 462) and Sansevieria (p. 698). 



Royal Botanic Gardens, Kew, 



Feb. 1922, 



J- H. Holland 





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