. Bulletin of the British Museum (Natural History). . Fig. 3 Phanerotinus cnsialus (Phillips). Latex mould of specimen shown in Fig. 4, showing impression of early whorls and a mould of the body whorl preserving the dorsal emargination and faint traces of its spines. BM(NH) G72, x 1 -5. not an oolite) of early Arundian age (personal communication M. Mitchell). Rose & Dunham (1978 : 29, 161) mention that fossils are not common in the Red Hill Oolite, but small simple corals, Koninckophyllum cf. praecursor and Palaeosmilia murchisoni, can generally be found together with specimens of th
. Bulletin of the British Museum (Natural History). . Fig. 3 Phanerotinus cnsialus (Phillips). Latex mould of specimen shown in Fig. 4, showing impression of early whorls and a mould of the body whorl preserving the dorsal emargination and faint traces of its spines. BM(NH) G72, x 1 -5. not an oolite) of early Arundian age (personal communication M. Mitchell). Rose & Dunham (1978 : 29, 161) mention that fossils are not common in the Red Hill Oolite, but small simple corals, Koninckophyllum cf. praecursor and Palaeosmilia murchisoni, can generally be found together with specimens of the tabulate coral Michelinia megastoma; they also state that the fauna is typical of the C,S| Zone. However, we are not entirely con- fident that the preservation of the originally larger shell (LZB 29) is identical to that of the other (LZB 34), which we understand was collected from a wall! The rock matrix of LZB 34 contains many crinoidal ossicles which do not occur in any of the other specimens. Description. Large-size discoidal gastropods, with coiling interpreted as dextral, but with the majority of whorls showing a characteristic wide open coiling. (Although the early whorls are preserved it is not possible to discern their character accurately.) The early whorls are partitioned off by a transverse septum, or septa, with concave side forward. Four to five whorls are present in the more complete specimens. Whorl cross-section subcircular but slightly asymmetrical, being rather wider than high and with the dorsal angulation closer to the inner margin. The upper and basal lips are sub-radial. The aperture is noticeably prosocline. A hollow spine-like extension of the outer apertural lip occurs in the lower third of the whorl circumference and produces a corona of large thom-like extensions; a much smaller and shorter spine occurs at the same level on the inner lip of specimen G72 while in IGS LZB 34 the inner side of the whorl is relatively smooth for much of its length but
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