III. FLORA OF BRITAIN. 395 



high ; for it can be made up only by including many dis- 

 puted species, and also reckoning many of the colonists 

 and denizens among the admitted natives. By the full 

 lists before j)rinted in this volume, it may be seen that 

 the number of species is taken at 1425, including colo- 

 nists and denizens, and also various quasi-si)ecies, scarcely 

 to be distinguished by any eyes besides those of their 

 local inventors, and mostly discarded by botanists who 

 are accustomed to look widely over the world's flora. By 

 a moderate reduction of one-third from the alleged species 

 in the excessively subdivided genera Ruhus and Hieracium, 

 the number will become 1400 ; and where an even figure 

 is wished for general comparisons, that may be the figure 

 assumed to represent the present flora of Britain, instead 

 of 1425. 



It is to be recollected, that in so reckoning the flora as 

 a collective total, various species are included which 

 never actually associate with each other. Though 

 brought together in book lists, they do not congregate 

 within the same area in nature. Erica ciUaris, restricted 

 to the vicinity of the south-west coast of England, — 

 Arbutus alpina, found only in North Scotland, — Andro- 

 meda polifolia, occurring in the intermediate latitudes 

 between those of the other two species, — Calluna vulgaris, 

 diffused from one extremity of Britain to the other, — are 

 all treated as if they were actual associates in counting 

 up a single united flora for the whole island. Numerical 

 results deduced from the total flora, though they may be 

 true as averages in books, are thus made to represent 

 numbers and proportions which do not really exist any- 

 where ; that is, which cannot be found in any single 

 or separate portion of the island, either provincial or lati- 

 tudinal. But there will doubtless always be a tendency 

 for the fallacies in one direction to balance those in the 



