51 
Ordinary Meeting, February 4th, 1879. 
E. W. Binney, V.P., F.R.S., F.G.S., in the Chair. 
“ The Area of the Middle Drifts as determined by their 
Contents,” by Alfred Bell, F.G.S. Communicated by 
R. D. Darbishire, F.G.S. 
The author, in working out the area of the middle drifts, 
commenced by pointing out the confusion produced by the 
sands, gravels, and boulder clays of the kingdom being con- 
sidered, as has been done by some geologists, of the same 
age. In proving this he has quoted the various forms that 
characterise the different deposits, showing that in some, as 
at Wexford, Bridlington, and in Scotland, the fauna under- 
lying the boulder clay contains many arctic forms which are 
wanting in the sands immediately above. These sands he 
further traces by their contents over the middle east coast 
of Ireland, the western and midland counties of England and 
Wales, the Isle of Man, and the east and south coasts of 
England. Having enumerated some of the derived rocks, 
obtained in one pit alone, with numerous crinoids and 
corals, a brief reference was made to the number and com 
dition of these latter forms, 35 species of which he had found 
in one collection alone. 
Having pointed out the character of the middle glacial 
marine fauna, he proceeds to show that the land fauna has 
been subject to the same mutations, the fauna following the 
climate. 
A list of shells, about 140 species, obtained from the drift 
gravels, forms an appendix to the paper. 
Proceedings— Lit. & Phil. Soc.—Vol* XYITL- No. 7.— Session 1878-9, 
