The Amuri Fucoid*

Abstract

The nature of the “fucoidal markings”—peculiar flattish conical surfaces with radiate flutings—that occur, for example, in the Amuri Limestone (Mangaorapan — Upper Bortonian) and overlying beds at Amuri Bluff has been the subject of much speculation amongst New Zealand geologists, and at times doubt has been cast on their supposed organic origin. Part of a large “fucoid” with straight, closely spaced radiating markings, thought to have come from Culverden, was described by F. W. Hutton in 1873 as “ Pinna plicata ” ( see Boreham, 1965, p. 21, Pl. 4, fig. 2).