. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CRETACEOUS FAUNAS FROM SOUTH AFRICA 179. Fig. 37. Peroniceras (Peroniceras) dravidicum Kossmat, 1895. SAS Z753, the holotype of P. (Zuluiceras) obliquenodatum van Hoepen, 1965. This specimen is transitional to subgenus P. (Zuluiceras). x 1. Specimens of P. (P.) dravidicum with more quadrate whorl sections and stronger ornament are in these respects transitional to P. (P.) subtricarinatum, SAS A609 and SAM-PCZ5946 (Fig. 32A). Typically, however, P. (P.) sub- tricarinatum has a quadrate to depress
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CRETACEOUS FAUNAS FROM SOUTH AFRICA 179. Fig. 37. Peroniceras (Peroniceras) dravidicum Kossmat, 1895. SAS Z753, the holotype of P. (Zuluiceras) obliquenodatum van Hoepen, 1965. This specimen is transitional to subgenus P. (Zuluiceras). x 1. Specimens of P. (P.) dravidicum with more quadrate whorl sections and stronger ornament are in these respects transitional to P. (P.) subtricarinatum, SAS A609 and SAM-PCZ5946 (Fig. 32A). Typically, however, P. (P.) sub- tricarinatum has a quadrate to depressed whorl section with very strong umbiH- cal bullae. In addition, the venter is generally more rounded and the coiling more evolute. P. (P.) dravidicum is the ancestor of P. (Zuluiceras). The transition in- volved the development of tighter coiling, retention of a single keel to greater diameters, and more prominent development of rounded ribbing on the outer whorls (Fig. 41). In fact, one of the paratypes of P. (Z.) zulu, SAS Z14 (Fig. 45), is still very close to P. (P.) Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original South African Museum. Cape Town : The Museum
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