288 IDENTITY OF EOCENE SPECIES ON THE VOLGA AND IN ENGLAND. 
Antipofka near Saratof on the Lower Volga. — The lowest beds of the tertiary 
rocks containing fossils in the east of Russia, with which we are personally ac- 
quainted, occur at intervals along the right bank of the Volga, below the city of 
Sarhtof, and notably at the large village of Antipofka, where they were formerly 
noticed by Pallas as constituting a “ conglomerate of shells.” From the descrip- 
tion of that author, we were disposed, on approaching the spot, to think, that 
these shelly beds, forming as they do the western edge of the low steppes of 
the Kirghis, would prove to be of very recent age, and represent simply the 
consolidated shingle and shells of a former Caspian Sea which advanced to this 
boundary, but examination soon taught us that their organic remains belong to 
the oldest tertiary period. At the base of the low cliffs on which Antipofka 
stands, or rather protruding through a talus of sand exposed in summer by the 
subsidence of the Volga to its lowest level (forty feet below the high watermark of 
spring floods), the beds most abundant in fossils are distinguished by a number of 
large concretions from six to eight feet long and four and five feet thick ; marking 
strata perfectly horizontal, which are made up of a profusion of shells, cemented 
in a gray sandy marlstone. The accompanying woodcut explains the succession. 
These shelly beds (a) are overlaid by yellowish iron-shot and whitish sands (&), 
with bands of compact, dark-coloured chert, from eight inches to one foot thick. 
Some of the alternating courses consist of greensand, others are made up of a 
devious net-work of siliceous, tubular forms which cross each other, and in some 
of the softer sandy layers are casts of shells. The low cliff terminates in ascend- 
ing order in beds of light blue marl passing into beds of sand (c), which in many 
parts are surmounted by drift and local detritus (x). 
LONGITUDINAL DETAILED SECTION AT ANTIPOFKA. 
Antipofka. 
Level of the Volga, 
Horizontal distance 2 to 3 versts. 
x. Drift of finely laminated clay and sand of brown colour, and with no foreign detritus. Bones of Mammoth, Bos and Rhinoceros occur 
in this deposit in the low steppes on the opposite bank of the Volga. 
£.(■<?. Siliceous sands with irregular concretions. 
-£j < b. Bluish-gray marly beds, in parts sandy, with casts of shells. 
£ L«- Large ellipsoidal concretions of sandy calcareous grit subordinate to clay and sand, with Eocene fossils (Bognor and London clay). 
Among the fossils we collected are Cucullcea decussata (Sow.), Pectunculus hre- 
virostris (Sow.), Venericardia planicosta (Sow.), V. (n.s.), Calyptraa trochi - 
