78 On the Silurian liocks of Bohemia, and 



mary limestone, than any portion of the upper Silurian masses. 

 This is so remarkably the case in the little ridge between 

 Nebetein and Olscham, which is thrown up in an anticlinal 

 form, and where the highly veined hard and scaly crystalline 

 limestone is so associated with talco-micaeeous schists, that 

 if we had not found fossils in it, we might have well presvmi- 

 ed that it was of much higher antiquity. At Rittberg, bands 

 of whitish hard quartzose conglomerate dip under the 

 black Strigocephalus limestone, and thus represent the sand- 

 stones, grits, &c., which occupy a simihxr place in the Rhen- 

 ish provinces ; whilst, at Gross Luttein, the limestone is 

 overlaid by a coarse grit and hard sandstone, in parts con- 

 glomeritic, whose exact relations we had not time to deter- 

 mine. This last mentioned rock occupies the higher wood- 

 lands, and in mineral character is not unlike some varieties 

 of the Carpathian grit ; but not being able to observe a junc- 

 tion, we forbear from attempting to determine the point. In 

 the mean time, it is enough to observe, that as up to the present 

 day, the grauwacke and limestone of the environs of Olmutz, 

 have not been dissociated on geological maps from the grau- 

 wacke and limestone of Bohemia, so is the value of the palaeo- 

 zoic classification made apparent. From what I already 

 know of the existence of true Devonian rocks in Upper Silesia, 

 and the country of Glatz, and from noticing great masses of 

 ancient stratified rocks on the westei'n borders of Moravia, 

 wliich, on the whole, plunge under the Devonian rocks of Ol- 

 mutz, I have little doubt that a zealous geologist, who could 

 devote a summer to the task, would be able to demonstrate 

 that strata of true Silurian age, like those of Bohemia, are 

 also to be detected in Moravia, and on the south-eastern 

 flanks of the Riesengebirge, and in the tract between Trop- 

 pau and Olumtz. At all events, it is to be hoped that the types 

 of both these systems being now pointed out in this central 

 region of Germany, the time will shortly come, when their 

 respective limits will be accurately laid down. 



I presume you are aware, that since Professor Sedgwick 

 and myself indicated the existence of certain large Producti, 

 &C.5 of the carboniferous age near Bleiberg in Carinthia, 

 which there surmount crystalline rocks, with encrinites of the 



