Isiv INTEODUCTION 



24. Longford. 



Central. Area 421 square miles. A small, flat, and rather 

 uninteresting county. The northern third is hilly, owing to the 

 presence of Silurian rocks, the prolongation of the Silurian area of 

 the north-east of Ireland. The highest point is Carn Clonhugh, 

 912 feet. The remaining two-thirds is typical Central Plain country, 

 level drift-covered limestone, with plenty of bog and marsh. One 

 or two small patches of Old Eed Sandstone occur. The Shannon 

 flows along the western edge of the county, and the Tnny traverses 

 the southern extremity to join the Shannon in the great river-lake 

 of Lough Eee, which fronts the county for many miles in the SW., 

 with deeply indented shores and numerous islets. Several small lakes 

 are scattered over the county, and in the NE. the greater part of 

 the mazy Lough Gowna, the source of the Erne, lies within the 

 boundary. Though occupying a position in the centre of Ireland, 

 97^ per cent, of the county is below 500 feet elevation. Grass covers 

 55, and crops 24 per cent, of the surface. The proportion of bog 

 is high — 12^ per cent. The only portion previously botanically 

 explored was the south-west by Messrs. Barrington and Vowell, 

 who have published the rarer plants of Lough Eee. Although the 

 flora of this division does not appear rich, there is no portion w^hich 

 will not bear further examination. 



Flora 544 species, the most interesting plants being those of the 

 Shannon group, on the Lough Eee shores. Eare or characteristic 

 species are few : — 



Viola stagnina, 4. Teucrium Scordium, 7. Chara tomentosa, 5. 



25. Roscommon. 



West-central. Area 950 square miles. This is almost entirely 

 a limestone area. In the north an undulation, where the slates and 

 sandstones of the Old Eed break through, forms the Curlew Moun- 

 tains (863 feet). In the extreme north, a small part of the high 

 Lough Allen coal-field belongs to Eoscommon, rising to 1377 feet 

 on the boundaries of Leitrim. An inlier of Devonian and Silurian 

 rocks in the east near Strokestown forms the Slieve Bane hills (857 

 feet). In the centre, rich grazing lands prevail, highly uninteres- 



