Because the nautiloid taxa reported here from various localities have been referred to in publications by authors from the nineteenth century onwards, a revised taxonomic nomenclature was employed whenever possible. For example, according to Serpagli and Gnoli (1977) Orthoceras bohemicum Barrande, 1866 is considered the senior synonym of Orthoceras fluminese Meneghini, 1857. Likewise, Serpagli and Gnoli (1977) referred to Meneghini's species as Orthocycloceras? fluminese (Meneghini 1857). Thus, any occurrence of Orthoceras bohemicum Barrande, 1866 is here reported as Orthocycloceras? fluminese (Meneghini 1857). Similarly, in its original binomen Orthoceratites subannularis Münster, 1840 was first changed to Orthoceras subannulare by Barrande (1866) and remained so for the following 112 years, before being assigned to Metaspyroceras Foerste by Zhuravleva (1978). Accordingly, all occurrences of this species are herein reported as Metaspyroceras subannulare (Münster 1840).