Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . ler clavate marginal (4) row of tubercles. The lateral (2)tubercles appear later, at c. 40 mm diameter, but these latter never reallybecome prominent. On the largest specimen, SAS-Z2098 (Fig. 244), the five rows of tuberclesare spread out evenly over the flanks, and the submarginal (3) row is the mostprominent, being distinctly pointed. Towards the larger end of this specimentuberculation on the flanks weakens, and ribbing becomes dominant. Theexternal tubercles, however, become stronger with increasing diameter andst
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . ler clavate marginal (4) row of tubercles. The lateral (2)tubercles appear later, at c. 40 mm diameter, but these latter never reallybecome prominent. On the largest specimen, SAS-Z2098 (Fig. 244), the five rows of tuberclesare spread out evenly over the flanks, and the submarginal (3) row is the mostprominent, being distinctly pointed. Towards the larger end of this specimentuberculation on the flanks weakens, and ribbing becomes dominant. Theexternal tubercles, however, become stronger with increasing diameter andstand out as prominent serrate ridges. The keel, at this stage, shows low undula-tions corresponding in number to the external tubercles. The suture is not well exposed in either of the specimens. Discussion This species was discussed extensively by Reeside (1962) and Young (1963)and not much can be added to their comments. The species is easily recognized by the very strong ornament when com-pared to other species of Af. {Delawarella), and may in this respect be considered. ABC Fig. 246. Menabites {Delawarella) delawarensis (Morton, 1830). SAS-Z2097. x 1. 324 ANNALS OF THE SOUTH AFRICAN MUSEUM
Size: 1983px × 1260px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
