I Chanced a few weeks ago to see, for the first time, a short paper by Mr. J. Wilfrid Jackson, F.G.S., in the Geological Magazine (Dec. V, Vol. V, p. 266) on “Mottled Foraminiferous Limestone in West and North Lancashire”. In that paper Mr. Jackson thus describes specimens of mottled limestone from Silverdale: “The matrix is light-coloured and fine-grained, with irregularly shaped patches (? nodules) of a fine-grained dark-coloured limestone. The patches have no definite shape, being mostly very uneven in size, some of them being long cylindrical bodies with irregular contours.”