KILLASSER, a parish, in the barony of GALLEN, county of MAYO, and province of CONNAUGHT, 6 miles (E. N. E.) from Foxford, on the river Moy and the road to Swinford; containing 6581 inhabitants. This parish was the scene of a sanguinary battle between the native septs of the Jordans and the Rowans, at a spot since called Lugnafulla, or "the valley of blood." It comprises 10,000 statute acres, of which about 6000 are arable and the remainder principally bog and mountain; the land is of indifferent quality and is in many places covered with rocks of great size; some of the eastern portion is more productive, but agriculture is in a very backward state; there is a large tract of irreclaimable bog. It is a vicarage, in the diocese of Achonry, forming part of the union of Templemore; the rectory is impropriate in the representatives of the late Roger Palmer, Esq. The tithes amount to £512. 0. 4., which is equally divided between the impropriator and the vicar. In the R. C. divisions it forms a separate benefice; there are two chapels, situated respectively at Calla and Boullabee, both well built and roofed with slate. About 90 children are taught in a public school; and there are five private schools, in which are about 450 children. There are several Danish forts in the western portion of the parish; at Calla is a small lake, in which is an island presenting appearances of fortifications, said to have been inhabited by the sept of the Rowans; at Erbull are the ruins of an old castle; and there are ancient burial-places at Killasser, Blackpatch, and Calla.