160 Igehtrom — On Bituminous Strata of Gneiss, ^c. 



the highly disturbed Permian epoch, the succession of a warmer 

 period, and then the return to cold in the Glacial epoch, when we 

 know that mountains were elevated to an extraordinary height and 

 extent, appear to me to tell a very consistent story of this part of 

 the history of our earth. 



No sooner was the north of Europe, and the land which masked 

 this country, depressed and submerged, than icebergs and field-ice 

 were borne down, and covered parts of this country,, of which we see 

 such interesting evidences in the Eastern Counties. 



In conclusion, I will add a few remarks on the distribution of 

 Proboscideans, which bear upon the subject. It has been a question 

 whether the Ehphas primigenius has ever been obtained from the 

 forest bed. Certainly its constant companion, the Bhinocer&s ticho- 

 rhinus, has not. The result of my own observation is that an 

 elephant resembling the Eleplias primigenius, in point of number of 

 the laminse of the teeth, is found not only in the forest bed, but in 

 the Norwich crag. This has been regarded by Dr. Falconer as a 

 type of Elephas prirmgenius, the true Elephas primigenius having 

 been a Post-glacial importation, together with the Bhinoceros ticho- 

 rhinus and the reindeer. They could pass into France and this 

 country, and live there long after some of their race had been 

 entombed in the ice of Siberia, That they migrated from the north 

 of Europe, driven by the cold, which their hairy and woolly coats 

 could not enable them to bear, is, I think, correct. That the 

 Mastodon Arvernensis, Elephas meridionalis, E. antiquus, E. priscus, and 

 others, migrated from the south-west with the Bhinoeeros Etruscus, 

 and that their remains were also carried into the estuarine deposit of 

 the Forest bed by a river flowing in the direction of the Ehine from 

 the south-west, are statements which are based upon long observa- 

 tion and experience. 



I. On Bituminotjs Strata of Gneiss and Mica Schist in the 



Province of Wermland (in the West of Sweden). By 

 L. J. Igelstrom. 



IN the north-western district of Wermland, M. Igelstrom has 

 discovered a hill consisting, in its central part, of hyperite, the 

 rest chiefly of common reddish granitoid gneiss. Beneath the central 

 hyperite and above the fundamental gneiss, there is a mass, twenty 

 Swedish fathoms in thickness, consisting of bituminous strata of 

 gneiss and mica schist. The bituminous matter is distributed every- 

 where throughout the whole mass of these strata, so as to be present 

 even in the smallest fragment and thence giving them a black colour 

 closely resembling gunpowder. When M. Igelstrom heated some 

 fragments in a retort of iron, there were formed combustible 

 hydro-carbons as gases, to the amount of nine per cent., and a com- 

 bustible oil, as well as a non-combustible, colourless oil were 

 collected in the receiver of the heating-apparatus. This interesting 



