At the present time we are only fully acquainted with the geology and palæontology of one division of the great Carboniferous Series developed in Devon and the adjacent counties, the Lower Culm Measures. This division, while representing only a small fraction of thickness of the Culm Measures as a whole, is of special interest both lithologically and palæontologically, as was shown by Messrs. Hinde & Fox in an admirable paper published in 1895. Above the limestones and cherts of the Lower Culm Measures lie the great thickness of sandstones and shales which constitute the Upper of the twofold primary division of these rocks instituted by Sedgwick & Murchison in 1840. The Upper Culm Measures occupy an area of more than 1,000 square miles, and are of Upper Carboniferous age.

With the exception of the researches of the late Townshend Hall, and more recently of Mr. Ussher, comparatively little has been added to our knowledge of these beds since the days of Sedgwick & Murchison, and of De la Beche. An inquiry with regard to the palæontology, and more especially the palæobotany, of these rocks has, however, been in progress for some time past, with the result that sufficient material has been gathered for a contribution to the fossil flora of the Upper Carboniferous rocks of Devon, which, it is hoped will be published shortly by one of us. While examining the sandstones and shales of this series, other discoveries have been made, incidental to the work of collection of plant-remains.