A CARBONIFEROUS FAUNA FROM NOWAJA SEMLJA. 179 



relationships, but it might be mentioned that it appears to belong to an undescribed 

 species bearing a certain resemblance to Brachymetopus ouralicus (de Verneuil), as 

 figured in Murchison's Russia, from which it differs, however, in the proportions 

 obtaining between the divided parts of the lateral segments, and in the nature of the 

 ornamentation on the three anterior axial rings. 



Ostracoda. 



Thin sections of the limestone show that carapaces of Ostracods are common, but 

 only a few could successfully be freed from the matrix. These are in excellent state of 

 preservation, the finer details being well exhibited. They appear to be undistinguish- 

 able from the following species : — 



Leperditia okeni (Miinster). 

 Bairdia curta (M'Coy). 

 Cytherella ? inflata (Miinster). 



General Remarks. 



Considering that the fossils described in this paper were found in a few fragments of 

 limestone, and these from a single bed, the great variety of groups and species is really 

 surprising ; representatives of most of the Lower Carboniferous invertebrate groups are 

 met with, with the exception of those which are usually absent from limestone strata — 

 the Cephalopods, for instance. 



So far as the evidence at hand goes, it seems probable that the bed yielding these 

 fossils was deposited in comparatively clear water at some distance from land, but not 

 necessarily at any great depth. The Protozoa, the Corals, the Crinoids, and the 

 Brachiopods grew in the midst of conditions eminently suitable for their development ; 

 it is therefore all the more remarkable that the Lamellibranchs and the Gasteropods 

 should be represented by so many dwarfed individuals. At the same time, these 

 dwarfing influences did not prevent the multiplication of species in the groups affected. 



As regards the stratigraphical position of the Cape Cherney limestone, the assem- 

 blage as a whole points to a Lower Carboniferous age, whilst the presence of many 

 typical species warrants us in assuming that the bed is probably in a series homotaxial 

 with the Productus giganteus zone of Russia or Upper Visean of Western Europe. 



The collection does not contain any of the species characterising the upper divisions 

 of the Carboniferous system, but at the same time not a few of the species cited in this 

 paper have been recorded from horizons higher than the Visean. However, with our 

 extended knowledge of the Upper Palaeozoic formations, competent palaeontologists have 

 found it necessary to extend greatly the range attributed to some of the more common 

 fossils ; these forms have probably undergone certain evolutionary changes, but since 

 these are often not discernible, new names have not been given to the apparently 



