. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . igh as wide (H/W = ). Primary ribs begin at the umbilical seam and are rursiradiate to the umbilical shoulder,where they bend forwards to become prorsiradiate and weakly falcate across the frequently bifurcate, or are separated by an intercalatory from the point ofgeniculation, so that twice as many ribs cross the venter as leave the umbilicus. There are 118 ANNALS OF THE SOUTH AFRICAN MUSEUM about 35 ribs per half whorl across the venter. Since the outer whorl covers the precedingwhorl to exactly the
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . igh as wide (H/W = ). Primary ribs begin at the umbilical seam and are rursiradiate to the umbilical shoulder,where they bend forwards to become prorsiradiate and weakly falcate across the frequently bifurcate, or are separated by an intercalatory from the point ofgeniculation, so that twice as many ribs cross the venter as leave the umbilicus. There are 118 ANNALS OF THE SOUTH AFRICAN MUSEUM about 35 ribs per half whorl across the venter. Since the outer whorl covers the precedingwhorl to exactly the level of bifurcation and intercalation, all ribs in the umbilicus aresimple. Periodic constrictions, each marked by a strengthened rib bearing a distinctumbilical bulla, cut across ribs to the posterior and parallel those to the anterior. Measurements Specimen D H W H/W U SAM-PCA1902 52 23 (44) 23 (44) 18(35) Discussion The Angolan specimen closely resembles figured material of K. theobaldianum andcomparison with other species is noted by Kennedy & Klinger (1985).. Figure 16Placenticeras kaffrarium Etheridge. x 1. Lateral view of SAM-PC A1869. UPPER CRETA CEOUS (TURONIAN-CONIA CI AN) AMMONITES FROM SAO NICOLA U, ANGOLA 119 Stratigraphical occurrence Kossmaticeras theobaldianum (Stoliczka) is a typical Lower Coniacian species,apparently restricted to the Austral Realm. It is recorded from southern India,Madagascar, Zululand and now Angola. Superfamily HOPLITACEAE Douville, 1890 Family Placenticeratidae Hyatt, 1900 Subfamily Placenticeratinae Hyatt, 1900 Genus Placenticeras Hyatt, 1900 Type species Ammonites placenta DeKay, 1828; by the subsequent designation of Meek, 1876. Placenticeras kaffrarium Etheridge, 1904Figs 5I-J, 11A-D, G-I, 16 1904 Placenticeras kaffrarium Etheridge, p. 89, pi. 3 (fig. 16). 19786 Proplacenticeras kaffrarium (Etheridge); Cooper, p. 6. 1989 Placenticeras kaffrarium Etheridge; Klinger & Kennedy, p. 268, figs 9-14A, 19-20, 22-99 {cum synon.). Materi
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
