X PREFACE. 



scarcely be treated of otlierwise than as isolated genera. It would 

 be hopeless to attempt a correct delineation of the families they 

 belong to -n-ithout extensive illustration from exotic plants. The 

 main points only are in these cases indicated, and further details 

 are entered into in regard to such families only as JRanunculacece, 

 Crucifers, JJmhellaies, etc., whose chief characteristic forms are 

 exemplified in our islands. 



The British stations of the species are given as general as possible, 

 being ijidicative rather of where a plant is likely to be found, than 

 of the precise spot where it has been gathered. In a territory so 

 thickly peopled and so much cultivated as the greater part of Britain, 

 wild plants vary much in frequency and in local distribution. A 

 species may, from accidental causes, almost disappear for a time 

 from one county, or become abvmdant in another where hitherto it 

 had been almost unknown ; but the general range of each species 

 has prescribed limits, now pretty well known for British Plants, and 

 which may well be stated in general terms. In this respect it will 

 be readily perceived how largely the Author has availed himself 

 of the close investigations and judicious criticisms displayed in 

 Hewett "Watson's elaborate ' Cybele Britannica,' and he trusts he 

 may not be accused of plagiarism if he has deduced the British 

 stations almost entirely from that work, sometimes using Mr. Wat- 

 son's own words, but always checking and occasionally modifying 

 the conclusions according to the data supplied by personal observa- 

 tion, or by the herbaria and other sources within his reach. The 

 general geographical areas prefixed in each case, for reasons to which 

 allusion will presently be made, are taken from the same herbaria, 

 from the Author.'s own herborizations, extending over a great portion 

 of Europe, and from the best Floras of the northern hemisphere, 

 such as those of Ledebour, Fries, Koch, Grenier and Godron, Asa 

 Gray, etc., aided by Nyman's useful compilation, more recently 

 published. 



The omission or insertion of doubtful denizens occasions consider- 

 able diversity in the number of species assigned to local Floras. 

 Some writers introduce not only every plant that has been once 

 found in an apparently wild state, however accidental or temporary 

 may have been its appearance, but also all plants generally cultivated. 

 They argue that whatever has once sown itself is likely to do bo 

 again, and to be again gathered as wild, and will much embarrass the 

 student if he does not find it in the Flora of the district; and, as to 



