. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . : B Figure 1 Diplomoceras cylindraceum (Defrance, 1816). SAM-PCZ9551 from locality 113, KwaZulu, St LuciaFormation. Maastrichtian a or b. An internal mould that retains the ribbing, x 1. OBSER VA TIONS ON THE SYSTEMA TICS OE DIPLOMOCERAS CYLINDRACEUM 173 INTRODUCTION The heteromorph ammonite Diplomoceras cylindraceum (Defrance, 1816), typespecies of the genus Diplomoceras Hyatt, 1900, is a conspicuous faunal element of theMaastrichtian stage by virtue of its near-cosmopolitan distribution, paper clip-like coilingand

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. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . : B Figure 1 Diplomoceras cylindraceum (Defrance, 1816). SAM-PCZ9551 from locality 113, KwaZulu, St LuciaFormation. Maastrichtian a or b. An internal mould that retains the ribbing, x 1. OBSER VA TIONS ON THE SYSTEMA TICS OE DIPLOMOCERAS CYLINDRACEUM 173 INTRODUCTION The heteromorph ammonite Diplomoceras cylindraceum (Defrance, 1816), typespecies of the genus Diplomoceras Hyatt, 1900, is a conspicuous faunal element of theMaastrichtian stage by virtue of its near-cosmopolitan distribution, paper clip-like coilingand, in some instances, gigantic size. It is also amongst the last surviving ammonitesbefore the demise of the Order Ammonoidea at the end of the Cretaceous Period. Diplomoceras typically consists of several straight shafts, connected by a series ofvariable U-shaped sections (Figs 1-6). Because of this loose coiling, post-mortemfragmentation is universal and complete specimens of the species are unknown. The earlywhorls were thought to have been coiled in a helix (cf. Wright 1

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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory