Having received an invitation from Mr. W. Stoddart to examine the collection of his late father, Mr. W. W. Stoddart, F.G.S., at Sneyd Park, Clifton, Bristol, I availed myself of the opportunity to do so in April last, and was interested in finding, among many other good British fossils, a new and undescribed Crustacean belonging to the genus Eryon, from the Stonesfield Slate of Stonesfield, Oxfordshire.