SPECIMEN, &c. Ixxix 



with gravel, principally consists. Srdly. the chalky^ which as 

 it is composed of a purer and softer form of limestone, deserves 

 to be distinguished from the oolitic. 4thly. the argillaceous, 

 such as the Oxford or Kimmeridge clays, together with any 

 other that may occur within the district, distinguishing as 

 much as possible such as are covered with calcareous gravel ; 

 and 5thly. the arenaceous^ of which the rock at the summit of 

 Shotover-Hill affords an example. 



As, however, the description of plants that grow on any one 

 of the above rocks must be supposed to vary with the character 

 of the soil, and as the latter may not in all cases be identical 

 with the siibstratum, it would be useful to notice every such 

 case of discrepancy by introducing a separate series of columns 

 for the soils, or at least by appending a note at the bottom of 

 the page in which the plant is noticed, with an asterisk refer- 

 ing to the locality mentioned in the column above, in which 

 the plant is stated to occur. 



The following Specimen taken from the first page of the 

 Index will serve to illustrate the method I have adopted, and 

 may, therefore, perhaps deserve insertion, though the geolo- 

 gical localities even of the few plants given require further 

 examination, before they can be looked upon as ascertained. 



Where nothing further has been remarked with respect to 

 the habitudes of a plant than its occurrence in one of the 

 Stations above enumerated, an horizontal line in the column 

 opposite to its name has been deemed sufficient to indicate the 

 fact: but in other cases, where the nature of the situation con- 

 genial to it has been more particularly ascertained, the same 

 is indicated in the above position. Thus opposite to Ranun- 

 culus repens, in the third column, an horizontal line is affixed, 

 in order to shew that it has merely been remarked, that 

 meadows and pastures are the spots most favourable to its 

 growth; whilst opposite to R. bulbosus the particular kiiid of 

 meadow-land, which it chiefly affects, will be seen specified. 



In conclusion I ought to repeat, what indeed has before 

 been stated in other language, that the principle on which this 

 Index is constructed proceeds not upon the existence of 

 an acknowledged connection between soil and vegetation, but 



