274 
CRETACEOUS ROCKS AT VOLSK, SARATOF, ETC. 
in low hills a few miles on the west of our route, and then advanced to the 
promontory of Kashpoor. The rock is well seen in the descent which the road 
makes from a plateau, obscured by black earth and detritus, to the Volga at 
Kwalynsk, where true chalk having a thickness of upwards of 200 feet, reposes on 
Jurassic beds (sands and shale, &c.) with Ammonites Panderi. As we moved with 
great celerity, being anxious to employ the chief remaining portion of the fine 
autumnal weather of 1841 in the survey of the coal country of the Donetz, we had 
not the means of accurately ascertaining either the horizontal or vertical limits of 
the cretaceous masses. We believe, however, that certain marls and marlstone, 
porcellaneous and sandstone bands with which the white chalk is associated, must, 
as at Kharkof and Kursk, be contained in the Cretaceous system. At Kerza the 
white chalk is seen in a promontory on the Volga, and the higher hills, ranging 
into the interior, are occupied by sands and sandstones. 
At Volsk, indeed, there is a clear section in which at least 200 feet of chalk 
with Belemnites, a Pecten resembling the Pec ten quinque- costatus, and fragments of 
the coralline Choanites, are capped by an equal thickness of whitish yellow sand, 
which passes upwards into bands of hard, compact, siliceous grit. 
The higher hills or superior strata to the south-west of Volsk are chiefly com- 
posed of bluish-gray, sandy, slightly micaceous psammitic shale of conchoidal frac- 
tuie, which is here and there porcellaneous (Kiesel-thon), and which passes into 
finely laminated, feriuginous and white sandstone with green grains. If the gene- 
lai airangement of the masses, in a country which is composed essentially of hori- 
zontal strata, be our guide, we should say, that these strata must overlie and form 
the upper part of the chalk exposed at the adjacent town of Volsk. We detected, 
however, in these beds imperfect casts of Nucula, Lucina, Turritella and other 
shells, which we were disposed at the time to consider tertiary. But our mate- 
rials are too vague, and the intermediate strata too little known, to enable us to 
decide the point, which we leave to be settled by our successors, simply noting 
by the way, that these beds may very probably indicate a passage from the Se- 
condary to the Tertiary deposits. 
Similar siliceous claystones and sands protrude at intervals through the drift at 
many places, and give rise to a sterile country. They range, in fact, over all the 
higher lands north and south of the city of Saratof, and are largely developed 
throughout the government of that name. In ascending from the lower grounds at 
Saratof, where we have described high cliffs of Jurassic shales and sands, we 
