. Bulletin of the British Museum (Natural History), Geology. 52 P. M. P. ZABORSKI. Fig. 40 Whorl section in Wrightoceras cf. munieri (Pervinquiere). Based on specimen See also Fig. 38a, b. Remarks. These specimens differ from the material referred above to Wrightoceras wallsi in their rather narrower venters which tend to become more distinctly rounded on the later whorls. The differences are, however, more of degree than kind and the two forms tend to grade into one another in the Ezillo population. The closest previously described species is W. munieri (Pervinquiere) which is distin
. Bulletin of the British Museum (Natural History), Geology. 52 P. M. P. ZABORSKI. Fig. 40 Whorl section in Wrightoceras cf. munieri (Pervinquiere). Based on specimen See also Fig. 38a, b. Remarks. These specimens differ from the material referred above to Wrightoceras wallsi in their rather narrower venters which tend to become more distinctly rounded on the later whorls. The differences are, however, more of degree than kind and the two forms tend to grade into one another in the Ezillo population. The closest previously described species is W. munieri (Pervinquiere) which is distinguished from its contemporary W. mirabilis (Pervinquiere) on sutural grounds alone. These two have virtually identical gross morphologies and, as suggested by Reyment (1954: 157), Benavides-Caceres (1956: 476) and Barber (1957: 53), they may be synonyms. Comparable material occurs in the Lower Turonian of the Negev, the Hoplitoides cf. mirabilis of Freund & Raab (1969: 65; pi. 10, figs 1, 2), and in Venezuela, the H. munieri and H. cf. munieri of Renz (1982: 100; pi. 31, figs 3-6, 11). Poorly preserved specimens from northern Mexico described by Bose (1920: 225; pi. 19, figs 1-3) also seem to be closely related. Wrightoceras inca (Benavides-Caceres 1956: 475; pi. 63, figs 6-11) is another similar form, said to be distinguished from W. munieri by faint, falciform ribs on the inner whorls. W. submunieri Wiedmann (see Wiedmann 1975: figs 6A-C; 1979: pi. 8, fig. 1; Wiedmann & Kauffman 1978: pi. 8, fig. 2) has a broader venter, more inflated inner flanks and strong ribbing on the early whorls; it resembles W. llarenai (Karrenberg 1935: 143; pi. 31, fig. 14; pi. 33, fig. 14). W.(l) gagnieri (Faraud 1951: 149; pi. 5, fig. 1) develops a rounded venter with flank ribbing terminating in ventrolateral tubercles. W. reymenti Collignon & Roman (in Amard et al. 1981: 57; pi. 9, figs 7a, 7b) has a very wide umbilicus, highly inflated whorls and a very broad, tabulate venter. Famil
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