O gatunku Endemoceras (Lyticoceras) Noricum (Roem.) z kredy dolnej niecki tomaszowskiej

Abstract

ON THE SPECIES ENDEMOCERAS (LYTICOCERAS) NORICUM (R O E M.) OF THE LOWER CRETACEOUS DEPOSITS FROM THE TOMASZÓW TROUGHSummaryDuring geological field works conducted in 1964 within the Tomaszów trough (north-western margin of the Świętokrzyskie Mountains – Fig. 1) the present author described the Lower Cretaceous (Valanginian – Hauterivian) section while examining an exposure at Wąwał.Among the representatives of the type Upper Valanginian ammonite assemblage (Astieria bachelardi S a y n, A. cf. sayni K i 1 i a n, Bochianites neocomiensis (d' O r b.), Leopoldia provincialis S a y n, L. quadristriangulata S a y n, Polyptychites cf. scalarinus K o e n., Saynoceras verrucosum (d' O r b.), the species Endemoceras Noricum (R o e m.) thought to be a guide form of the Lower Hauterivian, was for the first time found (Fig. 2) in this section (Table I, Fig. 3–7). This find was, however, not alone. J. Lewiński (l932), the first scientist conducting his works in this area, cited from the Lower Cretaceous of the vicinities of Tomaszów Mazowiecki the species Neocomites cl. amblygonius Ne y m a y r u. U h l i g also found among the fauna representatives of the Upper Valanginian. J. Pruszkowski working within this region in 1961–1962 mentions (1962) several, not identified ammonite fragments of the genus Neocomites U h l i g 1905, which are found in Valanginian deposits. I have determined them as Endemoceras noricum (R o e m.).Stratigraphical position of the genus Dichotomites bidichotomus (L e y m.), very abundant at Wawoł in the bed No. 5, i.e. above Endemoceras noricum (R o e m.), constitutes an additional problem there. In Germany (O. Seitz, 1950) and in Central Poland (S. Marek, 1961) the species Dichotomites bidichotomus (L e y m.) is thought to be characteristic of the Upper Valanginian, whereas within the Russian platform (I. G. Sazanava, 1962) it is referred to the Lower Hauterivian. The present author is of an opinion that acceptance of E. Braumberger's conclusion (l903) maintaining that this species passes from Upper Valanginian to  lower Hauterivian and, in consequence of this, cannot be regarded as a guide form of the Upper Valanginian, would be the best solution here.