^ 



OF RUBIACE^ IN TEOPICAL AFRICA. 251 



certained, and is difBcult to estimate, but I believe that it will not 

 exceed that of Eubiaeeae. 



General G-eggkaphical Distribution or Kubiace^. 



On comparing the number of species of Eubiacese in Tropical 

 Africa with that in other important or isolated regions, the fol- 

 lowing interesting summaries and estimates may be given, 



"We find that in the Cape Plora there are about lOG species ; 

 * see Harv. & Sond. PI. Cap. vol. iii. (18G4-18G5). In the ' Flora 



Orientalis' there are about 182 species; see Boiss. Fl.Orient.vol. iii. 

 (1875). In Algeria, Mumby gives in his ' Catalogus ' (1859) 39 

 species, which include 21 species of the critical genus Galium. 



In Spain, Wilkoram and Lange (1870) give 78 species, of which 

 53 are Galia ; in Britain there are 14-17 species, of which 10-13 

 are Galia ; and in the whole of Europe 171 species (Nyman, 1865), 



110 being Galia and 43 Asperulce. 



In the Deccan peninsula of India, Wight and Amott (1834) 

 give 155 species, including some obscure or doubtfully native 

 species ; in Ceylon, Dr. Thwaites (1864) gives 129 species. 

 ^ In British India it may be estimated that there are about 550 



species. 



In Dutch India it appears that there are also about 550 species. 



In Australia, Mr. Bentham (1860) gives 110 species. 



In New Zealand, Sir J. D. Ilooher gives (1864) 31 species, 24 



belonging to the genus Coprosma. 



In the British West Indies, Grisebach (1864) gives 173 species. 



In Brazil there may be estimated about 1100-1200 species ; for 

 this estimate I am indebted to Dr. Miiller, of Geneva, who is at 

 present engaged upon part of the Order for the ' Flora Brasiliensis.' 



„„4 +u« «^,r.,i>^noa tt-liprft Filices have more 



Mauri tiu 



than double the number of species as compared with any Natural 

 Order of Flowering Plants, Eubiacea? occupies the fourth place 

 among the latter, while CompositsB holds the sixth place. In the 



belong to Eubiacese. 



(the 



There is, of course, great probability that the standard of spe- 

 cific value varies much in the diflferent books from which, and with 

 the difi-erent authors from whom, the above numbers are taken, 

 and therefore any conclusions deduced from their comparison 

 must be held subject to this consideration. In my own work the 

 standard has been intended to be kept high, so that plants have 



