Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . Fig. 7. Exiteloceras bipunctatum (Schliiter, 1872). A-C. Topotype specimen GPIG-9. D. Straight body chamber fragment GPIG-10. Both specimens from the Upper Campanian of Ahhen, West Germany, x 1. ANCYLOCERAS BIPUNCTA TUM AND NEANCYLOCERAS 229 whorls are still coiled, and do not show straight or otherwise aberrant earlycoiling. GPIG-16 (Fig. 8D-E) ^hows labeceratid coiling but this is probablydue to post-mortem deformation. On the phragmocone, rib density is generally between four and five permaximum whorl diameter, but
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . Fig. 7. Exiteloceras bipunctatum (Schliiter, 1872). A-C. Topotype specimen GPIG-9. D. Straight body chamber fragment GPIG-10. Both specimens from the Upper Campanian of Ahhen, West Germany, x 1. ANCYLOCERAS BIPUNCTA TUM AND NEANCYLOCERAS 229 whorls are still coiled, and do not show straight or otherwise aberrant earlycoiling. GPIG-16 (Fig. 8D-E) ^hows labeceratid coiling but this is probablydue to post-mortem deformation. On the phragmocone, rib density is generally between four and five permaximum whorl diameter, but may be as high as eight. Some specimens, (Fig. 4C) and GPIG-13 (Fig. 9B), show slight irregularities in ribbingwhich may be interpreted as shallow constrictions. The sharp-crested, slightlyrursiradiate, bituberculate and even ribbing is characteristic of the major partof the shell. Stronger ribs appear only on the last part of the phragmocone andon the body chamber in some specimens. Straight and curved body chamber fragments can be identified. GPIG-5(Fig. 4B
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
