Article: The palaeontology of the Namurian rocks of Slieve Anierin, Co. Leitrim, Eire
On Slieve Anierin the Lower and Upper Eumorphoceras Stages of the Namurian contain an un-broken sequence of faunas; these are described in detail for the first time in Ireland. The simple geological structure enables marine bands to be collected in their undoubted order of superposition, in contrast to some equivocal sections elsewhere in Britain. Shale is the dominant rock type throughout the succession, but a thick grit, with coal seams, occurs in the lower part of E2.The faunas of the marine bands consist dominantly of goniatites and lamellibranchs, the most common gonia-tite genera being Eumorphoceras, Cravenoceras, and Cravenoceratoides, with Anthracoceras and Dimorphoceras abundant at certain levels. The goniatite species have relatively short time ranges and are unsurpassed for the recognition of zones and subzones. The lamellibranch species usually have longer time ranges, but are also shown to be valuable stratigraphically, supplementing the goniatites. The following new species and subspecies are described: Eumorphoceras rostratum; E. bisulcatum erinense, ferrimontanum, and leitrimense; Posidbnia cor-rugata elongata and gigantea; Caneyella membranacea horizontalis; Obliquipecten costatus; Posidoniella variabilis erecta; and Chaenocardiola bisati.Detailed stratigraphical correlations are made with beds of the same age in Ireland, the Pennine region in England, north-west Europe (notably Germany and Belgium), and North America. Some important revisions in correlation are suggested, and the remarkable extent of Namurian goniatite-lamellibranch faunas is demonstrated.