On the Junction of Gault and Lower Greensand near Leighton Buzzard (Bedfordshire)

Abstract

I. Introduction. Eighteen years ago the late J. F. Walker and myself described to the Society a remarkable fossiliferous limestone occurring immediately beneath the Gault at Shenley Hill near Leighton Buzzard. The bed differed, both in its lithological characters and in its fossil contents, from any other deposit then known at this horizon in England, and the problems which it presented demanded, and have received, further investigation. Walker continued assiduously to explore the palaeontology of the bed, until his work was cut short suddenly by death in 1907. Partly by personal visits to the locality, but mainly through the agency of the quarrymen, he had been able by this time very largely to increase his collection of the fossils, and had made progress in his study of the brachiopodfauna, which was his particular interest. It was his intention ultimately to deal exhaustively with this element of the fauna, and, as a preliminary step, he had already prepared and sorted many thousands of specimens into their proper specific relationship, with provisional determinations where possible. The collections thus arranged by his own hand are, however, all that remains to us of the work that he did after the publication of our joint paper. Some information culled from them will be given in a later part of the present paper. While my late colleague continued to explore the palaeontology of the Shenley bed, I devoted attention, as before, more particularly to its stratigraphical aspect. Visits in successive years constantly revealed new features of