1857.] COMMON PLANTS. 41 



those plants which have been ascertained to grow in fifteen or 

 more of the eighteen provinces into which Great Britain has been 

 divided for botanico-statistical purposes in the ' Cyb. Brit./ will 

 at once convince any one that such a standard of commonness 

 is a very unsatisfactory one. He will find species varying im- 

 mensely in actual abundance classed indiscriminately together, 

 undoubted rarities side by side with daisies, buttercups, and 

 nettles. 



For the purpose, then, of ascertaining more satisfactorily what 

 species would probably be voted 'common' by a majority of in- 

 dividual botanists, classifying according to their own experience, 

 let us suppose our island divided into districts of such size as 

 may be readily traversed and explored by a local botanist, — say 

 eight miles square, — we shall not then, I think, find much difii- 

 culty in separating all our Flora into four great classes. Class 

 A will comprise those plants which probably occur in at least 

 99 per cent, of such districts. These may be called Universal 

 Species. Class B will consist of plants likely to be found in at 

 least 75 per cent, of such districts. These may be called Com- 

 mon Species. Class C will embrace plants which may be ex- 

 pected to occur in 50 per cent, or somewhat more of such dis- 

 tricts. These we may term Frequent Species. To Class D th( 

 remainder of our Flora will belong, consisting of all such plant; 

 as may be supposed to grow in a decided minority, greater or 

 less, of such districts, and which therefore are justly entitled to 

 the appellation of the Uncommon Species. 



Now it seems to me that the plants which may be comprised 

 in Classes A and B are the only ones which can with justice and 

 propriety be called Common Plants ; and in this opinion I think 

 that I shall be supported by a decided majority of my brother- 

 botanists. The occupants of Class C are but at best entitled to 

 the denomination of Neutrals. 



But it may fairly be asked, — This is all very well, but is this 

 system of classification so easy as you fancy ? That, I grant, re- 

 mains to be proved. Let us however put it to the test, and see 

 how far the following attempt will prove satisfactory. 



Class A. — Universal Species (145). 



Ranunculus aquatilis. Eanunculus Plammula. Eanunculus repena. 



Ranunculus Picaria. Ranunculus acris. Caltha palustris. 



N. S. VOL. II. G 



