Publisher's Synopsis
The present paper is the second in a series describing belemnites from the upper part of the Upper Cretaceous of Great Britain and deals with the Upper Campanian and Lower Maastrichtian Belemnitella faunas from the chalk of Norfolk. Belemnites from the Coniacian to Lower Campanian chalks of Norfolk and southern England were described by Christensen (1991). The Upper Campanian Substage is characterized by Belmnitell di Orbigny, and species of this genus are used as index fossils in the North European palaeobiogeographic Province: B. mucronata (Schlotheim) in the lower part of the Upper Campanian, and B. minor Jeletzky and B. langei Jeletzky in the upper part. The Upper Campanian belemnite faunas comprise only species of Belemnitella , except in Scania, souther Sweden. Here Belemnellocamaz balsvikensis (Brotzen) predominates with subordinate B. mucronata in the lower Upper Campanian (Christensen, 1975, 1986). The Lower Maastrichtian belemnite faunas consist of species of Belemnella Nowak with sunbordinate Belemnitella . More than a score of species, subspecies, and varieties of Belemnitella from the Upper Campanian and Lower Maastrichtian have been established.;They were commonly erected on the basis of relatively little material, and the variation of critical characters was rarely studied by appropriate biometric methods. Christensen (12993) discussed most of these taxa and concluded that they are poorly understtod, and that the concept of individual species differs from one author to another. The North European Province (Boreal Provice of authors) extends from Ireland tp the Ural Mountains, but in contrast to the Coniacian to Lower Campanian no subprovices are recongnixed in the Upper Campanian and Masstrichtian. The aim of the present paper is to describe the Belemnitella faunas from the UpperCampanian and Lower Maastrichtian of Norfolk, utilizing biometric analysis. The Lower Maastrichtian Belemnella faunas have not been studied, because they have been described by Schulz (1979). The traditional Belemnitella zonation of the Upper Campanian is critically assessed, and the evolutionary trends of Belemnitella from the Santonian to Upper Maastrichtian are analyzed on the basis of 43 sample representing 20 species and subspecies.
