. Bulletin of the British Museum (Natural History), Geology. CENOMANIAN BRACHIOPODS FROM LOWER CHALK OF BRITAIN AND NORTH EUROPE 95 Schloenbach (1867: 494) described Rhynchonella mantellana [sic] from the mantelli and rhoto- magense Zones of northwestern Germany, placing in synonymy Sowerby's original Terebratula mantelliana and Roemer's (1841) T. paucicosta. Schloenbach's figured specimen (pi. 23, fig. 11) shows a flatter form with a more circular outline and only slightly produced beak; his concept of 0. mantelliana resembles only slightly the typical form which was, admittedly, rather poorl
. Bulletin of the British Museum (Natural History), Geology. CENOMANIAN BRACHIOPODS FROM LOWER CHALK OF BRITAIN AND NORTH EUROPE 95 Schloenbach (1867: 494) described Rhynchonella mantellana [sic] from the mantelli and rhoto- magense Zones of northwestern Germany, placing in synonymy Sowerby's original Terebratula mantelliana and Roemer's (1841) T. paucicosta. Schloenbach's figured specimen (pi. 23, fig. 11) shows a flatter form with a more circular outline and only slightly produced beak; his concept of 0. mantelliana resembles only slightly the typical form which was, admittedly, rather poorly illustrated by Sowerby (1826). His specimen seems closer to Roemer's T. paucicosta, from the Essen Greensand, and could even have been a young form of that species. It also resembles a specimen figured by Panow (1969: 570; pi. 109, fig. 4) and another by Popiel-Barczyck (1977: 30; pi. 1, figs 7-9) called Orbirhynchia mantelliana from the Lower Cenomanian of Poland, which, in addition, have a more broadly arcuate anterior commissure than true 0. mantelliana. Many geographical and ecological variants have now been included within this species, largely because their separation can be seen to offer no stratigraphical advantage. The species is listed prominently from the Totternhoe Stone, or just above it, from the type area in Berkshire, southwards to Wiltshire and Dorset and as far north as Cambridge, Lincolnshire and York- shire. There are also examples which fall well within the present range of variation from Cran d'Escalles near Cap Blanc Nez, northern France and from Brochterbeck, north Germany. Specimens which can neither be included here, nor, so far as I can see, within 0. paucicosta, occur in the Tourtia of Tournai, Belgium. This variant has also been collected from beds of a similar age at Montigny sur Roc, southern France. Specimens figured as Rhynchonella mantel- liana by Deicke (1878) and Wanderer (1909) are also probably referable to O. paucicosta (Roemer). Example
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