49© SCIENCE PROGRESS. 



clays, and the fauna is partly marine, partly freshwater, or 

 even terrestrial. According to Andrussow, at the end of 

 Sarmatian times the sea formed a number of basins, the 

 water of which, originally salt, gradually became brackish 

 and then fresh. The marine fauna slowly gave way to 

 freshwater forms ; and towards the beginning of Pliocene 

 times the basins had become large freshwater lakes (28). 



A general account of the younger Tertiaries of Rou- 

 mania is given by Fuchs (29). In the mountains which lie 

 between that country and Banat, in Siebenbiirgen, there are 

 a number of isolated basins of Tertiary rocks. They are 

 characterised especially by the occurrence of lignite-bearing 

 beds, with Cerithium margaritaceum and C. plicatum. 

 The best known of these basins is that of Bahna, north of 

 Vercierova, in which, besides the Cerithium beds, normal 

 Leitha limestones are found and marine marls with a 

 fauna precisely like that of Lapugy. The Cerithium beds 

 themselves have usually been correlated with the Pec- 

 tunculus sandstones of Hungary (Oligocene); but according 

 to Fuchs, excepting the two Cerithia mentioned, not one of 

 the fossils is Oligocene, while all, including the Cerithia, 

 are known to occur elsewhere in the Miocene. 



It is remarkable that the lio-nite beds are never met 

 with in Roumania, except in these isolated basins. They 

 are unknown in the true Roumanian basin, where we have 

 the following succession : — 



(e) Unio beds. Unio, Vivipara stricturata, etc. 



(d) Psilodont beds. Unio, Vivipara Alexandrini, V. Heberti, etc. 



(c) Congeria beds. Congeria stromboidea, etc., Unio, Vivipara, etc. 



(b) Sarmatian. 



(a) Salt-bearing beds. Ditrupa incurva occurs in an associated 

 Nullipore limestone. 



The salt-bearino- beds are correlated with those of 

 Wieliczka, and are placed in the Mediterranean stage ; 

 the Congeria beds represent not only the Congeria beds 

 (Pontian) of Austria, but also the Lower Paludina beds; 

 while (d) and (e) correspond with the horizons of Vivipara 

 bifarcinata and V. stricturata in Austria. 



The papers dealing with Tertiary deposits in other 

 areas will be noticed in subsequent articles. 



