. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. Fig. 114. Olcostephanus {Olcostephanus) baini baini (Sharpe) (<?). The holotype, in the British Museum (Natural History), x 1. Photo: W. J. Kennedy. radiate, terminating in 17-22 bullae on the body chamber, from which arise bundles of 3-5 prorsiradiate secondaries, with 1-2 intercalatories between bundles. Parabolae present on inner whorls only. Inflation decreases on adoral portion of the body chamber. Description Microconch (<?): the shell is small, rarely larger than 60 mm diameter, and invo
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. Fig. 114. Olcostephanus {Olcostephanus) baini baini (Sharpe) (<?). The holotype, in the British Museum (Natural History), x 1. Photo: W. J. Kennedy. radiate, terminating in 17-22 bullae on the body chamber, from which arise bundles of 3-5 prorsiradiate secondaries, with 1-2 intercalatories between bundles. Parabolae present on inner whorls only. Inflation decreases on adoral portion of the body chamber. Description Microconch (<?): the shell is small, rarely larger than 60 mm diameter, and involute up to the umbilical bullae on the inner whorls, so that about 80 per cent of the preceding whorl is covered, but becoming slightly more evolute as the umbilical seam egresses on the adoral portion of the body chamber. Conse- quently, a short distance of the secondary ribbing of the penultimate whorl is visible below the umbilical seam at this stage. The whorls are rather inflated, with a depressed whorl section, the latter tending to become coronate as the umbilical seam egresses. Prominent primary ribs begin at the umbilical seam and curve backwards (rursiradiate) to distinct, sharp umbilical bullae on the umbilical shoulder. Each bulla gives rise to two or three coarse, prorsiradiate secondaries, frequently with an intercalated rib between bundles. Where there are three secondaries per bundle the intercalated rib is usually absent. Often a rib which is seen to arise from a bulla on the one flank is found to be inter- calated on the other side. The secondaries recurve slightly so as to cross the venter transversely. In some specimens there may be a slight concave inflexion of the secondaries along the siphonal line. There are 14-18 bullae on the final whorl, with 17-18 secondaries per 6 bullae. The umbilicus is rather narrow and moderately deep, with steep umbilical walls and a subrounded shoulder. The slope of the umbilical wall lessens as the umbilical seam egresses. Th
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
