I have found no very decisive indication of the westward extent of ancient Leinster along the southern coast. However, the story of the Déisi migration shows no distinction between the Déisi settlements south of the Suir in County Waterford and those north of the Suir in County Tipperary. There is nothing to indicate that the Munster king settled one portion of his allies on conquered territory and another portion on territory already in his possession, and the whole tenour of the story associates the settlement with the displacement and dispossession of the Men of Ossory. Therefore, I think it probable that the territory of Ossory included the greater part of County Waterford, as far west as Cappoquin and the Blackwater from Cappoquin to the sea. As in the case of the eastern parts of Munster so in the case of the part beyond the Shannon, now County Clare, there is more than one story to account for the annexation. When several stories are given to explain a fact, though they contradict each other in the manner of the explanation, they form a strong corroboration of each other as to the fact itself. That Clare was at one time part of Connacht is the universal testimony of antiquity. Ancient Munster, therefore, the Munster of the heroic period, comprised the counties of Cork and Kerry, the greater part of Limerick and some small area of Tipperary and Waterford. It was the smallest of the Five Great Fifths and there is no need to bisect it to form two of them. The bisecting lines mentioned by Keating, however, are not likely to have been purely imaginary. They refer in my opinion to political boundaries of a later age. We have evidence of the division of Munster in early Christian times into what may be called two distinct spheres of influence. Besides the Eoghanacht dynasty which then ruled in Cashel, there were other branches of the same dynasty ruling in various parts of Munster. Of these the most powerful was the Eoghanacht of Loch Léin, also called the Eoghanacht of Iarmuma, "West Munster." Some of its kings are reckoned as kings of Munster, and hostile to the kings of Cashel. The dividing line from Limerick to Cork Harbour may indicate the boundary between the groups of states which acknowledged the eastern and the western authority. As regards the other line from Tralee to Slieve Bloom, I think it is founded on the fluctuating extent of the rival authority of the Dalcassian and Eoghanacht dynasties during the period between the battle of Clontarf and the Norman invasion. During that period we read of kings of the Eoghanacht lineage who are called kings of Cashel and Desmond. They are of the family of MacCarthaigh. North of the line, the power of the kings of Thomond was predominant. The boundaries of ancient Connacht are fairly certain. The Shannon throughout its course formed the principal limit. From the head of the Shannon to the sea at Donegal Bay the boundary was nearly the same as it still is.