consist in a predominance within the menihtes of the Clupeidae and 

 Gadidae — never recorded from the Jaslo shales — and also in the 

 rarity of forms with luminous organs (Pauca, 1931, 1933, 1934), (Kalabis 

 1948), (Horbacz 1957). Apart from differences concerning faunal com- 

 position, the mode of preservation of the fish remains also differs. 

 Among the menilites, in addition to complete specimens we may often 

 encounter shale layers some tens of centimeters thick, where detached 

 scales, vertebrae, and opercular bones are crowded in enormous 

 abundance. This points to facial conditions completely different from 

 those associated with the sedimentation of the Jaslo shales. The menilite 

 shales are in fact regarded as shallow-sea deposits (Pauca 1934). 



It is interesting to note the discovery in the Jaslo shales of Ru- 

 mania ^ — in the bed of the Bicaz stream and to the east of Cova- 

 sna — of fish scales or even complete skeletons. These belong to fishes 

 known, after Bancil, from menilite shales (Wdowiarz 1959). Hence, Ban- 

 cil supposes that within the Tarcau zone the Jaslo shales are an equiv- 

 alent of the menilitic series. The results derived from investigation of 

 ichthyofauna from the Jaslo shales of Sobniow provide little to support 

 B'ancil's supposition. Further conjectures cannot be based on this evi- 

 dence until the paleontology of the forms considered above is described 

 in detail; this particularly in view of the additional comparative ma- 

 terial which will be derived from descriptions of the ichthyofauna 

 from the Jaslo shales whose occurrence has been reported from the 

 Soviet Union and from Rumania (Wdowiarz 1959). 



BIOSTRATONOMIC ANALYSIS OF MATERIALS 



The lack of scales on most specimens, with the exception of indi- 

 viduals belonging to the genera Clupea L. and Equula Cuv., is a char- 

 acteristic feature of the preservation of the fish remains in the Jaslo 

 shales. On all the remaining forms, the scales have been preserved 

 merely as more or less distinct traces. In spite of the absence of scales 

 on the distinct majority of individuals, no accumulation of scales has 

 ever been reported from the Jaslo shales. Within the menilite shales, 

 on the contrary, are layers densely crowded with scales, although the 

 majority of fish remains there are likewise reported as destitute of 

 scales. In fact, the writer has succeeded in discovering among the Ja- 



5 In Rumania the Jaslo shales are referred to as "marno-carcarele" (Wdo- 

 wiarz 1955). 



40 



