ON THE BOTANICAL SUBDIVISION OF IRELAND. 61 



that they should be followed ; but it is not always possible to follow 

 them, on account of other considerations. The convenience of 

 county-divisions is so great, that, except in the subdividing of a large 

 county, it does not appear desirable to forsake county boundaries. 



Equalisation of Areas. — It is also desirable that, so far as possible, 

 the country should be divided into portions of approximately equal 

 area ; but here again the less the arrangement by counties is 

 disturbed the better. 



Utilisation of past or future Botanical Work. — It is manifestly 

 desirable that the scheme as regards subdivision of counties should 

 harmonise with the subdivisions used, or to be used, in published 

 or future county or local floras ; since this will save a large amount 

 of labour when it comes to working out the flora of each vice- 

 county. 



Nature of Bouyidaries. — Where a new boundary-line is required, 

 it is desirable that it should be something conspicuous — a railway 

 road, or river — in order that it may easily be found in the field ; 

 an imaginary line, such as a straight line between two places, though 

 it looks very well on a map, is often difficult to trace in the field. 



Let me now take up in turn each of the cases in which the plan 

 suggested differs from that proposed by Babington, explain the 

 nature of the change, and give the reasons. 



Cork. — Is now divided into three vice-counties (3, 4, 5), by two 

 N.W. and S.E. lines. Babington divided it into two vice-counties, 

 one much larger than the other, by the east and west course of the 

 Eiver Sullane and its continuation the Kiver Lee. In that useful 

 little flora. The Floicerinrj Plants and Ferns of the County Cork (1883), 

 the author, Rev. Thomas Allin, departs from Babington 's boundary, 

 and adopts instead "a line drawn along the Killarney Junction 

 Railway from the border of Co. Kerry to Millstreet, thence running 

 across the country in a straight line to Macroom, thence in a 

 similar line to Bandon, and from that town, following the Bandon 

 River, to the sea." * This line appears to have been wisely chosen 

 dividing the western mountainous portion of the county, with its 

 Atlantic, Highland and American plants, from the more level tract, 

 with its calcicole and Germanic species. The latter district (1747 

 square miles), being still considerably larger than the largest of the 

 counties which it is not proposed to subdivide, is conveniently 

 divided into two by the Great Southern and Western Railway from 

 Charleville to Cork, and thence by the western shore of Cork 

 Harbour to the ocean ; this line forms approximately the western 

 boundary of the Carboniferous limestone. The great county of 

 Cork is thus divided into three parts of almost equal area, the size 

 of each being about that of an average Irish county. As regards 

 the division of Co. Cork, I have had the advantage of the hearty 

 co-operation of Mr. R. A. Phillips, whose knowledge of the Cork 

 flora is well-known, and who suggested to me the sub-division 

 of the county adopted in this paper. 



Kerry. — In Babington's scheme Kerry is divided into two vice- 



Op. cit.. Introduction, p. xii. 



