18 OTHER LOWER SILURIAN SECTIONS. — UPPER SILURIAN OF GOTHLAND- 
shallow quarries and fold over upon the subjacent granitic gneiss, which occasion- 
ally surrounds them on all sides, and without the appearance of any intermediate 
sandstone. Such relations, indeed, we have already alluded to at the Egeberg 
near Christiania ; and it is so obvious that in no country can mineral characters 
be considered indicative of the relative age of beds, that we simply here make the 
remark, because we shall presently have to show, that in Russia the lowest mem- 
ber of the Silurian system is not a sandstone but a shale, the latter being there 
overlaid by sandstone. 
In certain quarries of argillaceous limestone at Freberga, to the north of Motala, 
we met with beds absolutely loaded with the circular bodies spoken of at Chris- 
tiania, Sphceronites aurantium (His.), Echinosphccrites (Wahl.), of the same species as 
those to which we shall afterwards have to allude near St. Petersburgh. They are 
there clustered together like bundles of enormous grapes, and are associated with 
one of the small Orthidae so common in the Russian deposits of the same age. 
Here again the beds, though entirely unaltered, are tilted at the high angle of 70° 
to the north, in the proximity of a hill of ancient granitic or syenitic rock, which 
had doubtless been heaved up en masse like the Omberg, whilst in all the lower flat 
beyond the slope of the limestone hillocks, and extending for many miles along 
the north-western shores of the Wettern See, the lower or fucoid sandstone lies in 
grand horizontal sheets, and is extensively quarried as a building stone. 
Upper Silurian Rocks. — Having thus satisfied ourselves concerning the true base 
of the Silurian rocks, and further of their close relations to strata of the Russian 
governments of St. Petersburgh and Reval, with which we were previously well ac- 
quainted ; and being further convinced that with very rare exceptions there are no 
traces of Upper Silurian rocks in the central or southern part of the continent of 
Sweden, it was not essential to our views of classification that we should visit 
Gothland, where such upper strata are so well known to abound. 
In fact, through the kind and liberal arrangements of Baron Berzelius and the 
assistance of our companion Professor Loven, to whose zeal, intelligence and good 
arrangements we were singularly indebted, the rich collections of Hisinger and 
Dalman were laid before us and a selection made from them, for the purpose of 
comparison with those of Great Britain, Russia and other countries. A glauce at 
the fossils which were brought to England and examined by other palaeontologists 
as well as ourselves, is sufficient to convince any one acquainted with the Silurian 
rocks of the British Isles, that whilst the long island of Gland is essentially com- 
