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CHALK OF THE COUNTRY OF THE DONETZ. 
visit (1841) Artesian sinkings had been made at Lugan to a depth of 630 feet with- 
out any indication of a change of rock. 
At Uspensk in the same district, where the chalk lies in hollows of the car- 
boniferous strata, we found Inoceramus crista galli, I. ( Catillus ) Cuvieri, Lima semisul- 
cata, Ostrea vesicularis, Belemnites mucronatus, &c. &c. Courses of flint, of white, 
gray, resinous and black colours, are there numerous. The whole of this creta- 
ceous mass, though unconformable to the subjacent coal strata, seems to have been 
simultaneously affected by a movement of elevation, for it dips with them to the 
north-north-east, though not by any means at so high an angle. But besides the 
pure white chalk, there occur in this same district, particularly to the north of 
Lugan, and between that place and the great coal-works of Lissitchia-balka, some 
small tracts in which greensands, apparently rising from beneath the chalk, are 
loaded with Exogyne, as well as with the Ostrea vesicularis. These portions of 
greensand extend to the right bank of the Donetz, in depressions of the older rocks, 
at Serebrianka and Verknaia. At the bureau of the mines at Lissitchia-balka, we 
inspected several fossils in a matrix of greensand derived from these localities, but 
none of them had the facies of the remains of lower greensand, all of them (in- 
cluding the Ostrea vesicularis ) being species of the white chalk and upper greensand 
of Western Europe. 
Before we leave the overlying deposits around these carboniferous tracts, we 
must further state, that on their southern frontier they are also surmounted by a 
narrow band of chalk, which, with a slight interruption, extends from the con- 
fluence of the Donetz and the Don on the east, to the rivers Miuss and Krinka 
on the west 1 . Again, on the eastern limits of this coal country we observed nu- 
merous instructive sections of white chalk, notably at Kamenskaya and on the little 
streams Slaboka, Glaboka, &c., tributaries of the Donetz. In several other locali- 
ties, which it is unnecessary now to specify, as their names do not appear upon 
our map, the white chalk is distinctly and conformably surmounted by a peculiar, 
white clay-stone, with marlstone and sands, the whole being perfectly analogous to 
strata in the government of Kursk, which we shall presently show to be an integral 
part of the Cretaceous system. 
In tracing the cretaceous rocks from these southern coal regions in their course 
i This hand of chalk is correctly laid down by Captain Ivanitzki in a geological map of this region, 
with which we were furnished by General Tcheffkine, and of which a reduction has been published in the 
‘ Annuaire des Mines de Russie.’ We have somewhat extended Captain Ivanitzki s band. 
