Some time ago the Manchester Museum purchased a selection of Coal-measure Fishes from the executors of the late Mr. John Ward, of Longton, and included with these were gutta-percha casts of two species of Arthropods. These were mounted on wooden tablets covered with green paper, one specimen being labelled: “Limulus trilohitoides, Buck. (Bridgewater Treatise, vol. ii, pl. xlvi, fig. 3). Roof of the Upper Bent Mine, Middle Coal-measures, Hunt Lane, near Oldham. Original in the cabinet of E. W. Binny, Esq.” The other: “Limulus rotundatus, Prest. Coal-measures, Oldham.”