82 
WHITE LIMESTONE WITH RED SANDS ON THE OKA. 
yellow limestone, containing Productus spinulosus (Sow.), P. antiquatus, and Litho- 
strotion jloriforme, are seen at Lutshki, where they repose on red argillaceous marls ; 
and a few versts lower down the river at Tiesholovo, twenty-five feet of similar red 
marls surmount a white limestone, twenty feet thick, which descends to the water’s 
edge. At Putshino, a few hundred yards beyond this spot, a section exposes 
the white limestone, charged with Spirifer Mosquensis, surmounted by red grit 
and resting upon white and rose-coloured marls, which alternate with other and 
thinner bands of limestone, containing the same characteristic shell. The cliff at 
this spot is not only interesting, in exhibiting the Moscow limestone subordinate 
to red and variegated sandstone and marl, but also in exposing a vast accumula- 
tion of calcareous tufa, not less than 110 feet thick, and charged with existing 
species of Helix and Limmea. As this tufa is seen to rest upon some of the car- 
boniferous stiata, it has probably exuded from other and higher layers of the same 
formation, in the manner represented in this woodcut. 
16. 
t. Calcareous tufa with Helices ancl Limnatce. 
c. Red sandstone. 
b. White limestone, with Spirifer Mosquensis. 
a, Reddish and white marls alternating with the Spirifer 
limestone. 
Outcrops of the limestone are also seen at the village of Tultshino ; but the most 
remarkable section, visible in any portion of this tract, is that of Kashirov, where 
upwards of 250 feet of strata are seen in the following order in ascending from the 
level of the Oka. 
Kashirov on the Oka. 
17. 
White marls, rising to the top of the cliff. 
Feet 
A. Reddish and white spotted marls 30 
g. Marly, schistose limestone, white as chalk 80 
f. White limestone in thick slabs 3 q 
c. Porous, sandy, hard limestone, in beds of three feet ’ ] 
d. Thin course of red marl ' l 
c. Soft micaceous green sandstone ’ 
b. Marly clay, spotted with red sand and thin courses of hard limestone. . . . ’ . 30 
a. White compact limestone, divided into strong beds of five or six feet thick 3o 
The upper beds are the most fossiliferous, but the same species of shells are 
found also in the lowest strata. Among these the most abundant are Orthis eximia 
