. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . gressively rursiradiate and S-shaped. Prominentconstrictions are already present on SAM-PCZ 18709 at a whorl height of 6 mm, andoccur on the whole phragmocone at a frequency of every 3/4 to 1 whorl. The suture is complex. The position of the siphuncle is interesting. Instead of followingthe centre of the flanks, it follows a course nearly perpendicular to the axis of coiling. Discussion Eubostrychoceras (E.) zulu has coiling similar to that of E. (E.) otsukai (Yabe, 1904)and E. (E.) protractum (Collignon, 1969), but
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . gressively rursiradiate and S-shaped. Prominentconstrictions are already present on SAM-PCZ 18709 at a whorl height of 6 mm, andoccur on the whole phragmocone at a frequency of every 3/4 to 1 whorl. The suture is complex. The position of the siphuncle is interesting. Instead of followingthe centre of the flanks, it follows a course nearly perpendicular to the axis of coiling. Discussion Eubostrychoceras (E.) zulu has coiling similar to that of E. (E.) otsukai (Yabe, 1904)and E. (E.) protractum (Collignon, 1969), but these are younger, Santonian-Campanianwith larger umbilical widths and different ribbing. Eubostrychoceras (E.) zulu superficially resembles E. (E.) japonicum (Yabe, 1904),which was comprehensively described and figured by Matsumoto (1977: 329, pi. 48(figs 1-4), pi. 49 (figs 1-3), pi. 50 (figs 1-2), pi. 51 (figs 1-2), pi. 52 (fig. 3)). However, inE. (E.) japonicum the early whorls are heterostrophic and with a Scalarites-like ornament 230 ANNALS OF THE SOUTH AFRICAN MUSEUM. enO o ju cx & o a U d a o o c S .SP o o U .2 X o o 3 ^o J GO t-- „ ptn 3 u 3 ^V ?a go in X >> o> o ;j3 CQ c3 o a o a .2o £ ;_^ C3 o o a <4-l U o <^ m 5 U CO ^ 5 o 03 03 1 3 3 00 03 i C2 s < go ^ ^ 5 a o Cu as CO o v— -Ci ?»* 3 -3 ^ 3*3 u o a S 1 § a !k C3 u o >J£ c3 & 1 O a 2*ao 5 1 < GO CRETA CEOUS FA UNAS FROM ZUL ULAND AND NA TAL, SOUTH AFRICA 231 (see Tanabe et al (1981: 216, text-fig. 1; pi. 35 (fig. la-e)), Okamoto 1988, pi. 7 (fig. 9))—quite unlike those of E. (E.) zulu. Here, the earliest known whorls are already coiled in acorkscrew with uniform ribbing and constrictions. We suspect that the earliest part of theshell may have been straight as in Hyphantoceras (H.) orientale (Yabe) as figured byOkamoto (1988, pi. 7 (fig. 8)), pointing away from the helix. Occurrence Coniacian II of KwaZulu. Eubostrychoceras (Eubostrychoceras) otsukai (Yabe, 1904)Figs 2B, 3A-B,
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
