26 INTRODUCTION. 



is separated into ISTortli and South by a line descending 

 the river Sullane from its entrance into the county to its 

 junction with the river Lee, and then following the course 

 of that river to the sea. Tipperary is conveniently divided 

 into North and South by the Great Southern and Western 

 Eailway. In Galway the division into East and West 

 is well defined by Lough Corrib and the river which flows 

 from it. In Mayo a boundary between the East and West 

 is also tolerably well marked by Lough Mask and the course 

 of the river Ayle as far as a small lake above Ballyhean 

 church; from thence it is imaginary for a short distance 

 until it reaches the road from Tuam to Castlebar close to a 

 hamlet called TuHy; then it follows that road as far as 

 Castlebar, and from thence descends the course of the w^ater 

 through Lough Cullin and by the river Moy to the sea 

 near Ballina. 



This division into Provinces has been adopted by Messrs. 

 Moore and More in their Cyhele Hibernica, but they have 

 not thought it desirable as yet to attempt determining the 

 distribution of the plants under the Counties separately. 



One inconvenience of the tabular form has already been 

 mentioned, another is that it does not give a very satis- 

 factory idea of the extent to which the country has been 

 examined. Eor instance. Provinces vi. South Wcdes, and 

 vii. North Wales, seem to be tolerably known; but in fact 

 only veiy small parts of them are in that condition. Few 

 or no Euhi are recorded from the counties of Glamorgan, 

 Brecon and Caermarthen, in S. Wales; or from Denbigh, 

 Flint and Anglesea, in N. Wales. Also it is only some 

 small parts of the other counties that have been examined; 

 viz, spots where a botanist interested in brambles has 

 been able to reside for a considerable time. 



