VI PREFACE. 



plants from continental botanists, nevertheless my Herbarium 

 does contain a considerable number of them. Reichenbacli's 

 Flora eocsiccata supplies a few, Eries's invaluable Herba/rimn 

 normale others, Wirtgen's Herbarium Rvhorum Rhenanorum 

 a considerable number j the Abbe Questier has given to me 

 a very extensive series of the French species, and I possess 

 others obtained from Dr F. Schultz and Professor C. Billot. 

 Unfortunately no botanist in Britain is known to have 

 typical sj^ecimens of the plants figured in the Ruhi Ger- 

 manici, of those described by Godi'on in the Flore de France^ 

 or by Boreau in his Flore du centre de la France. A few 

 also of those included in Arrhenius's valuable Monograplda 

 Ruhorum Suecice are unknown to me, although several which 

 I did not before possess have been kindly sent by Mr Joh. 

 Lange of Copenhagen. 



It is believed that the following essay will afford the 

 means of determining many, perhaps most, of our species : 

 but it is only by careful and long-continued study that any 

 person can expect to attain a correct knowledge of such 

 difficult plants. My hope is that the readers of this book 

 will endeavour to correct the mistakes into which I am 

 sure to have fallen ; for with the utmost care, and I may 

 venture to add that no care has been neglected, I cannot 

 avoid feeling convinced that the truth has only been 

 approached, and that perhaps rather distantly in some 

 cases. 



Several botanists of the highest eminence both in this 

 country and upon the European continent have thought that 

 all our brambles are infinitely varying hybrids or forms of 



