Amongst the numerous species of Trilobites which occur in the impure limestones of Bala age in Co. Waterford, two new and undescribed forms were recently found by me in the course of a preliminary examination of that area. At present the exact horizon of the beds has not been determined, but they may undoubtedly be referred to the Bala series. One of the new species belongs to the genus Cybele, and is a most bizarre form, with a long, snout-like projection of the anterior margin. The other is a new species of Trinucleus, bearing some resemblance to Angelin's T. bucculentus, which occurs in beds of “regio Ba” in Norway.