Aulina rotiformis , gen. et sp. nov., Phillipsastræa hennahi (Lonsdale), and Orionastræa , gen. nov.

Abstract

I. Introduction Phillipsastræa is a genus of Devonian Corals possessing certain well-marked characters. The genus Orionastræa has been established to include certain Carboniferous species very closely related to Lithostrotion , but which have been regarded by many writers as congeneric with those of Phillipsastræa. O. phillipsi (McCoy) is commonly known as Ph. radiata (Martin). Aulina is a new genus, found at the horizon of the Millstone Grit. One species only has been recognized: this has been confused hitherto with O. phillipsi , and hence recorded as Ph. radiata . I regard Phillipsastræa as the ancestor of Aulina , but do not consider that these are related to Orionastræa . All three genera, however, are colonial in habit, and possess a similar type of corallum: namely, that in which the individual corallites have lost their epitheca, and consequently are united by their dissepiments—a type of colony which may be termed ‘astræiform.’ The foregoing statements explain my reasons for including the history of the name Phillipsastræa and the description of its genotype in a communication primarily concerned with Carboniferous genera. I am deeply indebted to the late Prof. T. McKenny Hughes, to Dr. A. Smith Woodward, Dr. F. L. Kitchin, Dr. W. G. Lee, and Mr. Peter MacNair for the loan of material (including various type-specimens) preserved in the Sedgwick Museum, Cambridge, the British Museum (Natural History), the Museum of Practical Geology, the collection of the Geological Survey of Scotland, and the Glasgow Museum & Art Gallery; and to Mr. Charles Edmonds, Prof. E. J. Garwood, and