Upper Silurian non-graptolite fauna from the Chełm borehole (eastern Poland)

Abstract

Upper Silurian faunal assemblages are differentiated and tentatively correlated with graptolite zones. A description is given of 45 forms belonging to 19 families, 21 genera, 5 subgenera; 9 species of lamellibranchs are new. The above fauna shows close similarities with a synchronous fauna from the Barrandian of Czechoslovakia. The investigation of the non graptolite fauna has permitted a more accurate determination of boundaries of some graptolite zones previously recognized in the borehole here under consideration.