. Bulletin of the British Museum (Natural History), Geology. . Fig. 4 External and internal sutures of Anagaudryceras pulchrum (Crick). SAS 56, x 7 approx. Discussion. Anagaudryceras pulchrum closely resembles A. buddha when young, but the two species can be separated on the basis of the coarser lirae of pulchrum, scale-like collars, less depressed whorl section and more evolute coiling. Adults of the two species are clearly distinguished by the fold-like ribs of buddha. Anagaudryceras subtilineatum, a close ally from a somewhat higher horizon, appears to be more depressed when young and to po
. Bulletin of the British Museum (Natural History), Geology. . Fig. 4 External and internal sutures of Anagaudryceras pulchrum (Crick). SAS 56, x 7 approx. Discussion. Anagaudryceras pulchrum closely resembles A. buddha when young, but the two species can be separated on the basis of the coarser lirae of pulchrum, scale-like collars, less depressed whorl section and more evolute coiling. Adults of the two species are clearly distinguished by the fold-like ribs of buddha. Anagaudryceras subtilineatum, a close ally from a somewhat higher horizon, appears to be more depressed when young and to possess more markedly flexed lirae; it bears the same relationship to A. pulchrum as Anagaudryceras subsacya does to A. buddha. Gaudryceraspulvinatum Collignon (1964 : 30; pi. 324, fig. 1445) was separated from Anagaudry- ceras pulchrum on the basis of its Cenomanian age and differing proportions (at 48 mm diameter, Wb = 40%, Wh = 40%, U = 31%), plus a change from a depressed to a compressed whorl section as diameter increases and a consequent decrease in proportionate umbilical width; it is best regarded as a synonym of A. pulchrum. Anagaudryceras cassisianum (d'Orbigny 1850), from Cassis in the south of France, appears to be a close relation of A. pulchrum. From the figures of Fabre( 1940: 15; pi. 5, figs 8, 9) this species seems to have a smaller umbilicus than pulchrum at comparable diameters (30% as opposed to over 40 %), slowly expanding whorls which are strikingly depressed when young, more prominent lirae, and scale-like collars. More material is needed to determine its true affinities. Occurrence. Upper Albian of Zululand; Lower Cenomanian of Madagascar. Genus VERTEBRITES Marshall, 1926 Type species. Vertebrites murdochi Marshall 1926. Diagnosis. Very evolute, many-whorled serpenticone gaudryceratids retaining a depressed, sub- rectangular whorl section throughout ontogeny. Ornament consists of fine prorsiradiate lirae which are simple and rather prominent on the flank,
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