XXV.—Calathospermum scoticum—An Ovuliferous Fructification of Lower Carboniferous Age from Dunbartonshire

Abstract

The Clyde Plateau Lavas which are part of the Lower Carboniferous succession in the west of Scotland form the main mass of the Campsie Hills in Stirlingshire and the Kilpatrick Hills in Dunbartonshire. Below the lavas at the western end of the Campsie Hills are cement-stones and sandstones of the Ballagan Series. These are the lowest beds of the Carboniferous in this area, and in places are seen to overlie without apparent unconformity the Upper Old Red Sandstone. Few fossils have been found in them; the only plants so far recorded are Asterocalamites scrobiculatus Schloth. sp. and Alcicornopteris convoluta Kidst. (Walton, Weir and Leitch, 1938, p. 1345). All that may be said with certainty is that these beds are part of the Calciferous Sandstone Series and are probably the equivalent of the Cement-stone Group. In the Edinburgh area Alcicornopteris convoluta has been found at the base of the Cement-stone Group in beds which lie conformably on the Upper Old Red Sandstone. In the Kilpatrick Hills there are sandstones, shales and thin coal seams below the lavas in Glenarbuck and near the Loch Humphrey Burn. From the latter locality Scott (1924, p. 569) has recorded Calamopitys radiata Scott, C. zonata Kidston, Bilignea solida Kidst. and B. resinosa Scott, which were found in coarse volcanic ash.