In May last I had the honour of laying before the Geological Society a description of all the known British Cretaceous Patellidæ and patelloid Gasteropoda. Since then the well-known collector, Griffiths, of Folkestone, has forwarded to me a new limpet from Hythe, which appears to belong to the genus Hipponyx. The finding of a shell of this genus is remarkable, as hitherto the shelly bases were the only indications of the existence of Hipponyx in Cretaceous rocks in England, whilst Capulus Dunkerianus, d'Orb., was the only shell on the Continent, of this age, which could be referred to the genus.