. Bulletin of the Natural Histort Museum. Geology series. UPPER CRETACEOUS AMMONITE 83. Fig. 59 Sutures in Vascoceras obscurum Barber. A, at a diameter of 32 mm. B, at a diameter of 45 mm. C, at a diameter of 30 mm. D, at a diameter of 34 mm. All specimens from the Pindiga Formation, unit T2, Ashaka except which is from unit X at the same locality. 100, fig. 25 (with synonymy). 71989 Vascoceras hartti (Hyatt); Cobban, Hook & Kennedy: 49,figs49,91A-D,G-K. 1989 Fagesia superstes var. levis Renz; Meister: 37, pi. 16, fig. 2; text-fig. 26. 1992 Vascocera
. Bulletin of the Natural Histort Museum. Geology series. UPPER CRETACEOUS AMMONITE 83. Fig. 59 Sutures in Vascoceras obscurum Barber. A, at a diameter of 32 mm. B, at a diameter of 45 mm. C, at a diameter of 30 mm. D, at a diameter of 34 mm. All specimens from the Pindiga Formation, unit T2, Ashaka except which is from unit X at the same locality. 100, fig. 25 (with synonymy). 71989 Vascoceras hartti (Hyatt); Cobban, Hook & Kennedy: 49,figs49,91A-D,G-K. 1989 Fagesia superstes var. levis Renz; Meister: 37, pi. 16, fig. 2; text-fig. 26. 1992 Vascoceras gr. globosum (Reyment) ou Fagesia sp.; Courville: pi. 9, fig. 1. Material and occurrence. Two specimens, Pindiga Formation, unit X, Ashaka. Dimensions. , D Wb Wh U 79 49 83(105) 50(102) 33(42) 21 (43) 21 () 12() Remarks. These moderately evolute cadicones show sharp umbilical shoulders, which are undulating in , and steeply sloping umbilical walls. There are sharply rounded ventral ribs and occasional constrictions in (Fig. 58) but they fade by a diameter of 40 mm leaving the internal mould smooth but for transverse growth striae. Neither specimen shows umbilical tubercles. Kennedy et al. (1987: 51) pointed out the difficulty in distinguishing K/;ar/n'from globose V. globosum. They regarded a more evolute coiling and a steeply sloping umbilical wall as most useful in identifying the former. In these respects the present material is more properly referred to V. harttii than the similar V. globosum globosum. In the present work V. harttii has been found only in unit X at Ashaka. Meister (1989: 37-38) and Courville (1992: 424) also reported examples from unit U there which they referred to or compared with Fagesia superstes (Kossmat). As with V. globosum globosum (see above) these forms have an ontogenetic development characteristic of Vascoceras not Fagesia. The globose shape and complex suture pattern are not in themselves diagno
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