. Bulletin of the British Museum (Natural History), Geology. PROCERITHIIDAE, CERITHIIDAE & CERITHIOPSIDAE 125 Pictet & Campiche (1862) compared B. tecta with Cerithmm gurgitus Pictet & Roux (1849 • 280), yet, although all their specimens were internal moulds, they considered that the species were easily separated on account of their differing spiral angles (quoted as 37° or more for tecta and up to 27° for C. gtirgitus), while the latter was also considered to be more elongate. In addition to their different stratigraphical occurrence, B. tecta and B. neocomiensis (d'Orbigny) 1843,
. Bulletin of the British Museum (Natural History), Geology. PROCERITHIIDAE, CERITHIIDAE & CERITHIOPSIDAE 125 Pictet & Campiche (1862) compared B. tecta with Cerithmm gurgitus Pictet & Roux (1849 • 280), yet, although all their specimens were internal moulds, they considered that the species were easily separated on account of their differing spiral angles (quoted as 37° or more for tecta and up to 27° for C. gtirgitus), while the latter was also considered to be more elongate. In addition to their different stratigraphical occurrence, B. tecta and B. neocomiensis (d'Orbigny) 1843, can be separated by their slightly different spiral angles, although a comparison of their prominent carinae provides the easiest method of distinguishing them. B. tecta normally has two strong carinae, while B. neocomiensis has three, the first close to the suture, a strong central one and a third, which is far stronger than the third cord seen on the body whorl of B. tecta. Similarly, although it would seem that B. tecta occurs at a lower horizon than B. fouadi (Upper Albian), the two species can also be separated by ornamental differ-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original British Museum (Natural History). London : BM(NH)
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