A Specimen in the Ludlow Museum, which appears to he the lost type of Sowerby's species Orthoceras attenuatum figured in Murchison's Silurian System, plate 13, fig. 25, p. 632, from the Wenlock Shale of the “banks of the Onny River, near Stretford Bridge”, has been recognized by Mr. T. D. La Touche in rearranging and cataloguing the collection of local fossils. Owing to the fact that the large piece of rock (D. b. 49 in La Touche's catalogue) on which it occurs was fastened down to a tablet so as to expose only another specimen of a smooth and different species of Orthoceras, it had been completely hidden from view, as it was on the lower side. The specimen not only agrees in size, general characters, and rate of tapering with Sowerby's figure (though the annulations are sharper and narrower than there indicated), but it was also collected by Dr. Lloyd, as was the type, as stated by Murchison. The horizon (Wenlock Shale) is recorded on the existing label, but not the locality. However, Mr. La Touche, from his intimate knowledge of the rocks of the district, considers that the locality may well be that given by Murchison. A small portion of the upper end of the shell is now missing, corresponding to the imperfect non-annulated piece shown in the figure, but it seems to have projected freely out of the matrix, so it may easily have been broken off. Otherwise the specimen is in the same good condition as when Sowerby drew his figure, and we can have scarcely any hesitation in identifying it on the strength of the above evidence.