“Having often been puzzled to comprehend the manner in which,insome instances, large numbers of marine animals, such as Cuttlefishes, Crabs, Lobsters, and even Fish and Reptiles, have in past ages suddenly perished in their own element and been entombed, probably on or near the very spots where they had been hatched out, and which they had frequented all their lives, it has occurred to me that any suggestion as to causes now in operation which might have produced then, as now, the same result, will not be unwelcome to the geological student. in the ‘Principles of Geology’ (7th edit. 1847) Sir C. Lyell mentions (p. 743), among other causes, the shifting of currents which might result in the carrying away of banks of sand and mud, habitats of vast colonies of cockles and other molluscs; and the effect of a stormintearing up and casting ashore from their more solid bed great heaps of the edible oyster in the estuary of the Firth of Forthin1831, and numbers of living whelks.