PREFACE. v 



descriptions have been drawn up in the first instance from 

 British specimens (except in the few cases of doubtful natives). 

 They have been then compared with the characters given in 

 Hooker and Arnott's ' British Flora/ and Babington's ' Manual/ 

 or with detailed descriptions in some of our best local Floras. 

 They have, in almost all cases, been verified upon continental 

 specimens from various parts of the geographical range of each 

 species ; and a considerable number have been checked by the 

 examination of living specimens. The works of the best 

 French, German, Swedish, Italian, or other botanists have also 

 been consulted wherever the occasion required it. The dried 

 specimens made use of have been chiefly those of the rich 

 collections at Kew, including the unrivalled herbarium of Sir 

 William Hooker ; but the Author has also availed himself of 

 numerous and repeated observations made during forty years' 

 herborisations in various parts of Europe. 



" Taking into account the omission of all plants erroneously 

 indicated as British, it will still, no doubt, be a matter of 

 astonishment that, whilst the last edition of Hooker and 

 Arnott's * Flora' contains 1571 species, and that of Babington's 

 4 Manual' as many as 1708 (exclusive of Cliara), that number 

 is reduced in the present work to 1285. 1 This is not owing to 



1 The number of species (exclusive of Chara) described in the last 

 (eighth, 1881) edition of Babington's "Manual" is 1758, that in this 

 edition of Bentham's " Handbook" is 1296; that in the third edition 

 <1884) of my " Student's Flora " (which replaces Hooker and Arnott) is 

 1413. The difference between the Manual and Handbook is not (as it 

 is here stated by Bentham to be) " wholly owing to a different apprecia- 

 tion of the value of the species," but in a great measure to there being 

 included in the "Manual" many avowedly introduced and naturalised 

 plants. Nearly 150 such are enumerated in the Appendix to the 

 "Student's Flora," nearly all of which appear in the "Manual," but 

 not in the " Handbook." Of the 462 more species in Babington's than 

 there are in Bentham's work, 162 are comprised in the nine genera 

 Ranunculus, Rubus, Rosa, ITieracium, Rumex, Salix, Juncus, Potamogeton, 

 Carex, genera the limits of whose species are notorious subjects of con- 



