Plate XXXV. During the visit of the Yorkshire Geological and Polytechnic Society to Whitby, early in August last, two species of Gastropod Shells were found in the Upper Lias, both of which appear to be not only new to the Yorkshire Lias, but, so far as I have been able to ascertain, now to science. Both of these were found in the Jet Rock, or zone of Ammonites serpentinus, at Saltwick Nab, near Whitby. The interest of these discoveries will be appreciated when the following facts are borne in mind : first, that the Palaeontology of the Upper Lias of Yorkshire, and especially of the Whitby neighbourhood, has been very exhaustively worked out, especially as regards conchology, and that very little has been added since the publication of Messrs. Tate and Blake’s admirable work on the “Yorkshire Lias”; secondly, that these authors are only able to record two species of Gastropoda as having been found in the zone of Ammonites serpentinus in Yorkshire, namely Natica buccinoides, and Euomphalus minutus, although special facilities have been afforded by the mining of jet. It is also a very notable circumstance that both of these species were discovered by a lady—Mrs. Kendall. Actaeonina kendallii, sp. nov. The first discovered of the shells referred to is a species of Actaeonina, of which the following is a diagnosis: — Shell thin, ovate, whorls three, shoulder of whorls almost a right angle; space between suture and shoulder convex ; spire short; about 15 well-defined impressed spiral striœ ...