By A. J. Jukes-Browne, B.A., F.G.8. 329 
great plains of chalk which once covered the surface of England, 
and united England to France across the shallow trough which we 
eall the English Channel. 
Part II.—C.assiFicaTION AND NOMENCLATURE OF THE STRATA 
DEscRIBED. 
If we had merely to consider the neighbourhood of Devizes, or 
even the County of Wiltshire alone, the simplest arrangement of 
the Cretaceous Rocks would be to group all the Sands and the Gault 
Clay together as a lower division, and to regard the several members 
of the Chalk as an upper division. This was, indeed, the early 
classification adopted by Conybeare and Phillips in 1822, and by 
Fitton in 1827, but subsequent researches showed that it was not 
really a natural one. The earliest names used for the beds below 
the Chalk were Greensand, Gault, and Ironsands, the term Green- 
sand being invariably applied by Dr. W. Smith to the sands above 
the Gault, and including the Malmstone. 
The person chiefly responsible for the present nomenclature was 
Thomas Webster, who proposed the terms Lower and Upper Green- 
sand in 1824. They were suggested as a compromise, and only 
because certain persons had mistaken the green sandstone which 
occurs below the Gault at Folkestone for the true Greensand of 
Wiltshire. Fitton strongly protested against them, but they were 
retained by Murchison and others, who thought they were con- 
venient names and never realised the force of the objections which 
were brought against them. These objections were urged at various 
times by Dr. Fitton, Mr. Godwin-Austen, and Professor Judd. 
The term Lower Greensand as a name for the Ironsands is bad, 
because the general colour of these sands is not green, and because 
it unites under a common designation two groups which are widely 
separated in reality, one of them belonginy to the upper series and 
the other to the lower series of the Cretaceous System. The terms 
upper and lower can only be logically applied to parts of the same 
whole, thus we can speak of the Upper and Lower Chalk, or of 
