Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . B Fig. 38. Paratexanites pseudotricarinatum sp. nov. Var. B. Paratype NMB-D1060a. Compressed variety, x 0,76. CRETACEOUS FAUNAS FROM SOUTH AFRICA 53. Fig. 39. Paratexanites pseudotricarinatum sp. nov. Var. C. Paratype with inflated whorls, x 0,68. appears in the umbilical seam only at a relatively late stage, c. 25 mm. Herethese tubercles are flattened spinose, leaning against the umbilical wall. Withincreasing diameter the ventrolateral tubercles become less spinose, and moveaway from the umbilical

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Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . B Fig. 38. Paratexanites pseudotricarinatum sp. nov. Var. B. Paratype NMB-D1060a. Compressed variety, x 0,76. CRETACEOUS FAUNAS FROM SOUTH AFRICA 53. Fig. 39. Paratexanites pseudotricarinatum sp. nov. Var. C. Paratype with inflated whorls, x 0,68. appears in the umbilical seam only at a relatively late stage, c. 25 mm. Herethese tubercles are flattened spinose, leaning against the umbilical wall. Withincreasing diameter the ventrolateral tubercles become less spinose, and moveaway from the umbilical seam, eventually to expose the fourth row of tuberclesat a diameter of about 60 to 70 mm. Simultaneously, the whorl section becomesmore rounded, lacking a distinct umbilical edge. Very faint indications of tuber-culation become visible at midflank, foreshadowing the development of lateral 54 ANNALS OF THE SOUTH AFRICAN MUSEUM

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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory