396 
SECTION NEAR BOGOSLOFSK. 
to the north along the river Losva, and by travelling along their western edge, 
through a country chiefly occupied by greenstone, w T e came to the largest masses 
of palaeozoic limestone which are known upon the eastern flanks of the chain. 
Though perforated on all sides by eruptive rocks (greenstone, greenstone porphyry, 
&c.), and in numerous places converted into metamorphic masses with mineral 
veins, such limestones (the normal palaeozoic deposits of this country) are seen to 
occupy a long, narrow tract to the north and south of Bogoslofsk. These strata 
extend from the Lobva on the south to beyond the river Sosva on the north, or 
for upwards of 100 versts, and are traversed not only by those two streams, but 
also by the Kakva, Turya and Vagran. (See Map, PL H.) Our personal exploration 
of this long calcareous zone consisted in making traverses from the western edges 
of these palseozoic rocks, by Bogoslofsk, along the Turya, to the copper mines of 
Turyinsk on the east, and also by descending the river Kakva to the gold mines of 
Peschanka 
In the woodlands at the western end of the Zavod lake at Bogoslofsk we met 
with some bands of limestone (PL II. fig. 6), but owing to the intolerable perse- 
cution of mosquitoes, and the slight elevation of the rocks above the soil, we 
could discover few fossils sufficiently distinct to characterize the strata in this loca- 
lity, which we believe to be Silurian. At the eastern extremity of the lake and 
on its southern side, strata of grey and white splintery limestone occur in highly 
inclined and vertical positions, in which we detected Pentamerus Vogulicus, (nob.) 
with a second species of this shell ; and these inclining to the east are surmounted 
at a high angle by a reddish limestone, with Orthis Arimaspus (Eich.), Terebratula 
nuda, T. prisca, with Favosites Gothlandica and other corals. It is from this same 
band, as well as from the environs of Petropavlosk, that the fossils collected by 
Colonel Helmersen were communicated to M. v. Buch, which he has published as 
Silurian 2 . We agree with that author in viewing the chief limestone at the Zavod 
1 We were furnished on the spot with a very instructive geological map of this tract by Captain 
Karpinski, in which the outlines of the limestones and every intrusive rock are laid down. Towards 
the talcose and quartzose axis of the chain, the chief eruptive rock is marked by him as syenite, whilst 
the limestones are surrounded and cut off by greenstones, &c. The metalliferous zone is flanked on 
the east by serpentine, granite, &c. We can now however refer our readers to Colonel Helmersen’s 
second part of his ‘ Reise nach dem Ural und der Kirgisen Steppe’ (1833 and 1835), in which are given 
a map and sections descriptive of the same country around Bogoslofsk and Petropavlosk. 
3 See Von Buell’s ‘ Beitrage zur Bestimmung der Gebirgsformationen in Russland.’ Among the 
fossils identified and described by M. von Buch from the limestones near Bogoslofsk are, — Terebra - » 
tula prisca ( Ter affinis, Sil. Syst.) ; T. nuda, V. Buch; T. didyma, Dalm. ( Atrypa didyma, Sil. Syst.) ; 
