807 



omitted species which may be subsequently discovered within the 

 same tract, thus becomes doubly worthy of being recorded; its dis- 

 covery not only adding a positive fact to the sum of recorded know- 

 ledge, but also correcting the negative error implied in the omission 

 of that species. 



In the Botanist's Guides the lists do not profess to be complete ; 

 being simply compilations of such localities for the rarer species as 

 had been ascertained at the dates of publication. It does not appear 

 that in the first Guide any fixed list or choice of species was uni- 

 formly adopted ; a species which was included in one county list 

 being exckided from another. The negative evidence is thus vitiated, 

 and even rendered nugatory for several of the less rare species. In 

 the ' New Guide,' on the contrary, a fixed list of species was adopted 

 uniformly for every county, the localities of the same plants in each 

 successive county being entered as far as known. The omission of 

 any of the species from any county list was thus equivalent to an in- 

 timation of no locality for that species, in that county, having been 

 found on record or otherwise ascertained. To a considerable extent, 

 therefore, the county lists of the ' New Guide ' may be held to point 

 out what was unknown as well as what was known, at the date of 

 publication. Here, again, the discovery of any omitted species may 

 be said to have a two-fold value and claim for public announcement ; 

 first, by adding another locality for that species ; secondly, by adding 

 another species to that county list. It would be easy to show that 

 numerous localities published in the ' Phytologist ' do truly come un- 

 der this head of double value, although intermingled with others of 

 no value. 



In ' Remarks on the Geographical Distribution of British Plants,' 

 the ranges of latitude and elevation were given, as well as various 

 other items of information connected with the distribution and locali- 

 ties of all the known British species. Any locality discovered higher 

 or lower, more north or more south, than the limits there assigned to 

 the species, might thus at once be pronounced a positive addition to 

 the sum of our ascertained knowledge ; and, as such, might fairly be 

 deemed worthy of record. I shall, however, not dwell on the 'Re- 

 marks ' here, but pass to the ' Cybele Britannica,' — the work which 

 has led to my offering the present suggestions, through Mr. Newman's 

 (I may be allowed to say, judicious) note on the same subject. I 

 wish to show from that work what ample opportunities still remain 

 within the reach of our botanical explorers, for bringing fresh sup- 

 plies of useful facts to the already accumulated stores, and without 



