. Bulletin of the British Museum (Natural History), Geology. . Fig. 1 Endocostea (Selenoceramus) cf. semaili sp. nov; Tridens' Zone, Lower Maastrichtian, Nagoryani, Ukraine; right valve; M. Mackay Collection, BM LL 41653, x 0-5. Fig. 2 Endocostea ?<Cataceramus) sp. indet.; 'Tridens' Zone, Lower Maastrichtian, Nagoryani; M. Mackay Collection, BM LL 41654, x 0-5. Zone'. When compared with sixteen specimens from Nagory- ani in the collections of The Natural History Museum, it is fairly certain that the type of this nominal species is badly distorted. It has become much more elongated than all
. Bulletin of the British Museum (Natural History), Geology. . Fig. 1 Endocostea (Selenoceramus) cf. semaili sp. nov; Tridens' Zone, Lower Maastrichtian, Nagoryani, Ukraine; right valve; M. Mackay Collection, BM LL 41653, x 0-5. Fig. 2 Endocostea ?<Cataceramus) sp. indet.; 'Tridens' Zone, Lower Maastrichtian, Nagoryani; M. Mackay Collection, BM LL 41654, x 0-5. Zone'. When compared with sixteen specimens from Nagory- ani in the collections of The Natural History Museum, it is fairly certain that the type of this nominal species is badly distorted. It has become much more elongated than all of them except one. The latter specimen, BM LL 61647, has a normal, rather rounded, right valve, but diagenetic distortion has decreased the height of the left valve. The similarity of the form of the sculpture of this left valve with that of Kner's figure suggests that his specimen was also similarly distorted. For this reason I consider that Endocostea kneri is a nomen dubium until such a time as its true shape can be described, possibly when the Inoceramidae from Nagoryani are revised. Specimens from Nagoryani are illustrated in Figs 1 and 2. Endocostea semaili sp. nov. is very similar to E. (Catacera- mus) baltica (Boehm, 1909; see Geirs, 1964: pi. 1, fig. 1 only) from the late Santonian (? and Lower Campanian) of Ger- many, but it differs in having the umbones slightly more posterior. Also the comarginal ribs are much more regularly curved in Boehm's species, giving it a very rounded appear- ance, whereas there is a slight straightening of the ribs ventral to the umbones in E. semaili. The nature of the internal rib of E. (Cataceramus) baltica is in doubt. Inoceramus sornayi Dhondt (1993) was a nom. nov. for Inoceramus regularis d'Orbigny, 1846, non Munster, 1840; the lectotype was designated by Sornay (1962), and other specimens were figured by him (Sornay, 1976: pi. 2, figs 3, 4; pi. 3, fig. 4). /. sornayi is from the late Campanian and has a wide internal rib, and like
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