On the Correlation of the Cretaceous Formations of the North-east of Ireland

In a former communication I described “The Rhaetic and Lower Liassic Rocks of the neighbourhood of Belfast”*, and I now propose to continue the subject with a description of the strata which surmount the Liassic series, namely, the Upper Cretaceous rocks in part. An incentive to study these formations was the knowledge that the results of the labours of the late Robert McAdam, Esq., F.G.S., had been anxiously looked for by many geologists†, who hoped that the true relationship of the Irish Cretaceous beds would have been satisfactorily determined by him from the study of his own collection of local fossils. That geologist has passed away from amongst us without having accomplished these researches; and as his collection has not been applied to the furtherance of the much-desired object up to the present time, I have undertaken the task he may have intended to perform. During a residence of two years and a half in Belfast, I have worked assiduously in collecting fossils from the Irish Cretaceous strata, and in studying their lithology and stratigraphical characters, with the hope that these materials would enable me to correlate them satisfactorily; and I shall now endeavour to show that they belong to the so-called Upper Greensand and to the Upper Chalk. The general features of the disposition of the Neozoic rocks in the neighbourhood of Belfast may be understood by reference to the accompanying section. II. Absent Formations. 1. Oolitic Strata .—In the foregoing section, the Cretaceous beds