Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/55

 mian beds of Yorkshire and Lincolnshire, and shows their relation to those of Hanover, Westphalia, and Brunswick. The Speeton- clay series he considers to be the keystone in the correlation of the beds over the whole area.

In a subsequent paper Mr. Judd gave an interesting account of a series of beds between the Neocomian and Wealden strata of the south coast. The section where they were first noticed some years since by Mr. Godwin- Austen and Prof. E. Forbes is at Punfield, in the Isle of Purbeck, whence Mr. Judd suggests the name of " Punfield Formation " for these beds, which he shows to be of considerable importance, having a wide range through Prance, and being closely related to the coal-bearing strata of the north of Spain described by M. de Verneuil. The fossils are mixed and of a peculiar type ; and there are many species common to the English and Spanish series.

Mr. S. Sharp subdivides the Oolites of the Northampton district, and shows that the line of division between the Great and the Inferior Oolites in the neighbourhood of Northampton is marked by unconformity as well as by organic remains. He states that there are four areas, within a comparatively small space, in which the whole of the beds occurring in each, from the Great Oolite down to the Upper Lias inclusive, are accessible. The Northampton Sands he proposes to class in three divisions — the Upper, Middle, and Lower. Though the beds vary considerably in thickness, according to the different localities, the total thickness of the Northampton Sands may be taken on an average as about 80 feet.

Mr. Mitchell suggests that the valleys of the Oolitic district round Bath are due not so much to denudation as to the circumstance that many of the beds of Great Oolite are old coral-reefs of limited ex- tent, while the argillaceous strata are true sedimentary deposits overlying and wrapping round them, so that the Oolitic beds never in fact extended across the present valleys, though the clay beds did.

Mr. R. Tate continues his researches on the fossils of the different divisions of the Lias in Gloucestershire, and shows the value of the Ammonite-zones over certain areas — also that although the conditions of depth and deposit of the upper part of the Lower Lias are repeated in the lower part of the Middle Lias, there is a total change in the fauna, whence he infers a break in the stratigraphical succession.

Prof. Ramsay states, in an interesting paper " On the physical Relations of the New Red Marl, Rhaetic Beds, and Lower Lias," that