Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . B Fig. 167. A. Texanites soutoni natalense ssp. nov. Paratype SAS-Z2199. x 0,76. B. Texanitespresoutoni natalense ssp. nov. Paratype SAM-PCZ5885. x 0,72. 220 ANNALS OF THE SOUTH AFRICAN MUSEUM NMB-D1320 are also referable to this species plexus, although positive refer-ence to any of the above varieties is not possible. Variation in respect of strengthof ornament and whorl section is as considerable as in the adult SAS-H127B/1 (Fig. 183B) and SAS-H126E/1 (Fig. 181B) suggestthat the specimens with
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . B Fig. 167. A. Texanites soutoni natalense ssp. nov. Paratype SAS-Z2199. x 0,76. B. Texanitespresoutoni natalense ssp. nov. Paratype SAM-PCZ5885. x 0,72. 220 ANNALS OF THE SOUTH AFRICAN MUSEUM NMB-D1320 are also referable to this species plexus, although positive refer-ence to any of the above varieties is not possible. Variation in respect of strengthof ornament and whorl section is as considerable as in the adult SAS-H127B/1 (Fig. 183B) and SAS-H126E/1 (Fig. 181B) suggestthat the specimens with more compressed Submortoniceras-like whorls occurhigher up in the sequence than those with more inflated whorl sections. Twosets of specimens with similar relative proportions at equal diameters,SAS-Z1146-Z1147, SAS-Z1871, SAS-H126E/1, and SAS-Z1952E, SAS-H127E/1, SAM-PCZ 5886 respectively, again illustrate the variation in strengthof ornament (Figs 181-183), NMB-D1320 is more inflated than any of theother juvenile specimens, and may possibly belong to another Fig. 168. Texanites soutoni natalense ssp. nov. Paratype SAS-H126B/2. Typical form. X 0,89. CRETACEOUS FAUNAS FROM SOUTH AFRICA 221 Interrelationships of varieties The majority of specimens in the present collection belong to the typicalform, whereas the other two varieties are poorly represented. Due to lack ofsufficient stratigraphic data, the temporal relationship of the different varietiesis not very clear. We know only that the typical Submortoniceras forms areyoungest, and that those forms with smooth Submortoniceras-likQ inner whorls
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
