THE DISTRIBUTION OF PLANTS. 51 



Putting aside philosophical generalisations, and direct- 

 ing attention to the distribution of plants through the 

 counties of Britain, and the particular stations of our 

 rarer species, we shall find materials much more ample ; 

 and instead of wanting facts, they will be found to accu- 

 mulate upon us so rapidly and numerously, that the great 

 difficulty is how to condense this information into a small 

 space suitable to my present aim. Notwithstanding this, 

 however, there are still many of the northern and western 

 counties, regarding the floral productions of which we are 

 most imperfectly informed. To my present purpose this 

 want is of less consequence ; the particular details of 

 stations, and sketches of the distribution of individual 

 species, being reserved for other works, as such would 

 materially interfere with and distract from the more com- 

 prehensive generalisations sought here. 



Unfortunately, along with the trustworthy materials 

 there has gradually accumulated such a large intermixture 

 of errors, that difficulties beset us on every side, as to 

 what we may rely upon, and what is to be rejected in toto. 

 In general it appears that the local Floras * are the most 

 worthy of reliance, as referring to limited tracts, the pro- 

 ductions of which usually pass under the eyes of the 

 authors, and are submitted to due examination. I fear, 

 however, that one or two of our later Floras are faulty in 

 this respect ; species being admitted on insufficient au- 

 thority, and without the expression of any uncertainty on 



* There are seven county Floras; namely, for Devon, Oxford, 

 Bedford, Cambridge, Anglesea, Northumberland and Durham, and 

 Lanark : and six for tracts including portions of different counties ; 

 namely, those of Bath, Tonbridge Wells, Midland Counties, Berwick- 

 on- Tweed, Edinburgh, and Glasgow. Some of the county Floras, 

 however, do not keep strict limits. Catalogues of the rarer plants of 

 South Kent, Stockton-on-Tees, and Cumberland, have recently ap- 

 peared as separate works. And still more recently we have a valu- 

 able little work on the Natural History of Yarmouth, including a 

 Flora of its vicinity. 



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