1868. | Geology and Palzxontology. 411 
term, of an ancient lake or arm of the sea. Sir John regards the 
roads as having been formed by material which fell from the hill- 
side above the lake to lower levels beneath the water, until at the 
water-level a shelf was formed. He regards the loose material on 
the hill-side as lying at the angle of repose, so that all accessions 
would roll into the water and be arranged beneath it at the same 
angle. The width and slope of the roads would thus be dependent 
on each other, and would be determined by the depth to which the 
water was affected by waves. “In fact the lower level of the roads 
marks the lower edge of the disturbed water, just as their upper 
edge coincides with its upper edge. We thus see why the three 
shelves are so similar in size, and also why their width is least when 
their inclination is greatest.” 
Mr. Tylor’s paper ‘On the Amiens Gravel” is an attempt to dis- 
prove the well-known conclusions of Mr. Prestwich respecting the 
relative age of Quaternary deposits, and the date and manner of the 
excavation of the valleys on the sides of which they rest. The 
Amiens gravel is selected for this paper because, probably, it yields 
a typical example, and one to which a large amount of attention has 
been drawn. Mr. Tylor’s principal conclusions are, (1) that the 
surface of the chalk had assumed its present form prior to the depo- 
sition of any of the gravel or loess now seen resting upon it; and 
(2) that the Quaternary deposits indicate a Pluvial period, just as 
the Northern drift indicates a Glacial. 
Dr. Nicholson’s paper “On the Graptolites of the Skiddaw 
Series” is a contribution to descriptive Paleontology of a very use- 
ful kind, but, as recent criticisms appear to indicate, of somewhat 
debateable value. 
The scope of the elaborate paper “On the Glacial and Post- 
glacial Structure of Lincolnshire and South-east Yorkshire,” by 
Mr. Searles V. Wood, jun., and the Rey. J. L. Rome, is difficult to 
chronicle. It is a description of local phenomena, and an attempt 
to assign to them the causes by which they may conceivably have 
been produced. On two points, however, it possesses a more gene- 
ral interest, namely, (1) in the separation of the Boulder-clay of 
Hessle from the true Boulder-clay of the eastern counties, and from 
the purple clay which in the district under consideration overlies it, 
and in the determination of the younger age of the first-named 
deposit than the true Boulder-clay ; and (2) in the assignment of 
the so-called “ Bridlington Crag” to an horizon included within the 
limits of the “purple clay.” 
We are glad to learn from the Annual Report that the Society 
continues in a flourishing condition, no less than sixty-two new 
Fellows having been elected during last year, amongst the names of 
whom we notice those of Earl de Grey and Ripon, Mr. R. H. Scott, 
