INTRODUCTION TO THE FLORA. 243 



indicates the 50 yard point to which its station or stations are 

 nearest. By Professor Phillips, the late Mr. Gray, and others, the 

 heights of many of our prominent hills and of various points in 

 the dales were many years ago ascertained, and now, in the 

 maps of the Ordnance Survey, we are furnished with all 

 that can possibly be desired in this respect. In stating 

 both upper and lower limits I have gone upon the principle of 

 keeping within the mark. A species which occurs from the 

 valleys upward to a height of 1,900 feet has its Range given as 

 0-600. A considerable number of species which grow upon the 

 Main Limestone of Mickle Fell at about 2,500 feet are given at 

 0-800. In those cases where I have not myself seen the localities 

 for a plant I have, of course, had to estimate its altitudes as well 

 as I could, but there are very few of the higher stations that are 

 mentioned which I have not personally examined. 



In the concluding portion of the paragraph devoted to each 

 species is described in the first place the character of the stations 

 in which it grows, woods, grassy places, cultivated fields, etc., as 

 the case may be ; and after this is given a summary verbal outline 

 of its distribution. The word ' Valleys ' is only used in the 

 restricted sense to which allusion has been made ; it covers no 

 more than the New Red Sandstone and Kimmeridge Clay tracts 

 of the geological map. What is said respecting the frequency 

 of a species will of course be understood to be limited by what 

 is said with regard to its range ; a species may be thinly scattered 

 over a wide range or abundant within a limited range, though 

 the converse holds true usually. For many of the less frequent, 

 or more geographically interesting species, the names of the places 

 in the neighbourhood of which they grow are given ; but it is 

 only for the rarities that I have thought it needful to indicate 

 special stations with any degree of minuteness. In enumerating 

 places I have almost always begun with the north-west and pro- 

 ceeded towards the south-east. ' On the west,' if used without 

 any qualification, means on the west of the Central Valley; 'on 

 the cast' refers in the same manner. Of the books which have 



Aug. 1889, 



