POSTSCRIPT. 
~ St. Petersburg, August 1845. 
tbn\rh b ave n w| S I 1 ’ 1906 f CT ° Ur V ° 1UmeS W6re Pr!nted > but before the y wer e put into general circula- 
Plate VI. Thus, through our friends M Par lr b TT ° bSerVatl ° nS “ RuSsia t0 im P rove ° ur Map, 
Mr. Frears, a resident at Moscow we Wd thatl tl b ^ ^ *”* * ^ cal ™ d 
Belemnites, had been observed to form ti t m r 1 pisolite containing 
that metropolis (Gregorievo Podolsk Miatchk ^ J " raSS1C de P 0slt (Oxfordian) at several places around 
vwr -nt 11 A 8 7 ’ Miatchkova, Bronmtzi, and on the little river Koloksha near 
Vladimir). In all these places the pisolite is, we are assured 1™ M p 4 . , . , 
r U . r , , , , . , . we are assured by M. Pander, precisely identical with that 
of Popdam m Courland ; and m the government of Moscow it reposes directly upon the carboniferous 
limestone The zea ous researches of these Russian friends have, in fact. greatl/exLded our knowledgl 
of the limits of the Jurassic deposits, particularly of the overlying sandstones, which seem to occupy con- 
adorable portions of the plateaux, leaving the carboniferous limestone exposed in the larger river valleys 
and gorges only. In a tract north of Medinsk the Jurassic shale is so bituminous, that it mig^tt 
(7-245). " er ° US dCP0Sit ’ like C6rtain beds ° f the described by us near Simbirsk 
ar0Und ?? W We may a,S0 reraa,k - that M. Pander has detected remains of 
Mammoth and Rhinoceros m reddish clay covered by erratic blocks eight versts to the south of Verchni 
17 b nt “ 77 I : lo calities fractured flints of the carboniferous limestone are seen to alternate 
of M c b 7 n6S PXtinCt ^“P 6 ' 13 had ' indeed * been previously found in the vicinity 
oscow, but their true original position was unknown, as they had usually been picked out of the river 
eds into which they had fallen from the contiguous cliffs. The observations of M. Pander are, there- 
. ’ mp rtanl: * n com incing us, that such remains occur in an ancient drift : we may well believe 
animals of which these are the bones, were floated out to sea from the nearest lands of a former 
epoc l, and theii skeletons deposited (like those near Taganrog, p. 502) in gravel, sand and clay. In one 
spot 300 versts south of Petersburg, and twenty versts south of the river Kolomenka, M. Pander further 
found the horns of a stag in gravel or drift twenty-one feet below the surface, and covered by fine yellow 
sand, which is surmounted by clay and northern erratic blocks. 
Our last visit has also been productive of some additional acquaintance with the limits of the Silurian 
and Devonian rocks south of St. Petersburg. Thus, whilst the country south of Gatchina, and for some 
versts to the south of that town, is composed of a yellowish magnesian limestone, containing Silurian 
Orthidse and Trilobites (similar we believe to those species found by us in the strata on the Vloia, p. 30*) 
true Devonian rocks succeed near Sivoritzki at about twelve versts south of Gatchina, in greenish grey” 
micaceous sandstone and marly limestone, followed, at some versts further south, by red sands and sand- 
stone, identical with those of Dbrpat and of the river Mgra near Vitegra. Ichthyolites are found, at 
4 Y 
