126 



baker's north YORKSHIRE. 



GEOGRAPHICAL ANALYSIS OF THE NORTH YORKSHIRE FLORA. 

 TOTAL AREA OF NORTH YORKSHIRE 2II2 SQUARE MILES. 





Number of 

 species. 



Per centage of 



total 



native flora. 





86 

 71 

 53 

 8o 

 362 

 166 

 76 



10 

 8 

 6 

 9 

 41 

 19 

 8 









5 General Ascending Species 



6 Scattered Ascending ,, 



7 Local Ascending ,, 



Total number of native species. 



882 





For each of the drainage districts, as we pass them under 

 review, a table similar to the above will be given : and it is very 

 interesting to note the dififerences in respect of the way in which 

 their floras are made up which the different districts show, and 

 to attempt to trace out how far the difference in the composition 

 of the nine floras runs parallel with the difference in the physical 

 character between the nine districts. Upon comparison of the 

 analytical table which is given for each district with what is 

 stated respecting its physical geography it will be seen that, in 

 point of fact, this parallelism does exist to a remarkable extent. 

 The districts which are comparatively rich in Montane species 

 are those which have the most extensive and highest tracts of 

 hilly ground : the districts which are comparatively rich in 

 Xerophilous species are those which have a continuous extent 

 of dry rock and dry surface soil with tabular hills and steep- 

 banked dales : and the Rarer Ascending species are highest in 

 number in those districts which contain the greatest extent of 

 low-lying level country. And it so happens invariably that when 

 the number of species of any of these geographical categories 

 comparatively predominates in a district, that there most 

 of the species of that category grow in greater abundance than 

 they do in a district in which the number of species is small. 



