. Bulletin of the British Museum (Natural History), Geology. 242 CLEEVELY & MORRIS Diagnosis. Broad, turriculate or cyrtoconoid shell with even whorls, which are ornamented by smooth or noded spirals. Margin of outer lip fairly deeply opisthocyrt. Basal lip weakly indented, or curved slightly in the direction of growth. Remarks. Cossmann (1909: 167-8) provided the first detailed description of Cassiope, mention- ing the deep opisthocyrt growth lines and the sinus they produce in the centre of the whorl (Akopyan (1976: 20) considered the sinus was slightly above the centre). KoUmann (1979:
. Bulletin of the British Museum (Natural History), Geology. 242 CLEEVELY & MORRIS Diagnosis. Broad, turriculate or cyrtoconoid shell with even whorls, which are ornamented by smooth or noded spirals. Margin of outer lip fairly deeply opisthocyrt. Basal lip weakly indented, or curved slightly in the direction of growth. Remarks. Cossmann (1909: 167-8) provided the first detailed description of Cassiope, mention- ing the deep opisthocyrt growth lines and the sinus they produce in the centre of the whorl (Akopyan (1976: 20) considered the sinus was slightly above the centre). KoUmann (1979: 37) commented on earher definitions of the genus and stated that these did not consider the great variability of form and ornament that occurred, an aspect referred to by Schenk, 1969. Akopyan (1976: 132) described the characteristic features of Cassiope as 'very stocky shells with conical outlines having very strong spiral ornament of tuberculate "ribs"; these large tubercles being regularly rounded and separate from each other'. Although acknowledging the value for comparative purposes of his generalized description, we do not agree with his descrip- tion of the ornament. Availability of the generic names. Glaucoma Giebel (1852: 185) is a nomen nudum as no species are listed, no comment is made, nor is any reference given. Herrmannsen's (1852: 57) reference to the same genus is another nomen nudum. The first use of the name Glaucoma in a descriptive sense for gastropods was by Stoliczka (1868: 209). Cossmann (1909: 167-8) was the first to designate Cerithium kefersteinii Muenster in Goldfuss, 1844, as the type species for this taxon, even though it was for the nomen nudum Glauconia Giebel; we comment upon the selection of the type species below. Thus Glauconia Stoliczka 1868, non Gray 1845, is a junior objective synonym of Cassiope Coquand 1865. Cassiope Coquand (1865) is not preoccupied by Cassiopeia Peron & Leseuer (1810), a member of the Scyphomedusae. The di
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