Ill 

 esteemed authors and anticipated its publication by a 

 prodromus or synopsis of its contents. This has been 

 the origin, and intention of this little tract ; in execu- 

 ting it , I have added thereto a list of such species as 

 though long known in other regions were unlooked for 

 denizens of the Spanish soil, and others concerning 

 which it seemed desireable to have confirmed ac- 

 counts , or precise localities. I have passed over most 

 of those species which are common every won the bor- 

 ders of the Mediterranean, and many more which the 

 imperfect nature of the specimens rendered it difficult 

 to decide upon , nor have I named Portuguese plants , 

 when already cited by Brotero, exept for some special 

 purpose either of elucidating rarer species , or of re- 

 cording new stations. This little catalogue thus 

 composed will perhaps be not altogether unuseful 

 as tending to illustrate the vegetable geography of 

 the northern hemisphere. On this account I have fre- 

 quently insisted in the notes on the affinities , which 

 have been rarely attended to , of the distribution of 

 species at the two extremities of the Mediterranean 

 under the same latitude, and this not in herbs and 

 annuals which travel easily, but in permanent or arbo- 

 rescent species, and in mountain vegetation. The 

 Canarian Flora first drew my attention to this sub- 

 ject. Our knowledge likewise of the vegetation of sou- 

 thern Europe, which has been the object of too many 

 isolated labours, is obstructed by a mass of puzzling 

 synonyms. As far as time and circumstances would 

 permit, I have striven to clear away some of this ac- 

 cumulation af Augean rubbish, and where I shall be 

 found to have erred, the cause of error will have doubt- 



