54 REPORT — 1844. 



true upper Silurian rocks are found ; so that the whole of these highly fossiliferouB 

 regions belong to that period of animal life at which vertehrated animals did not exist. 

 This absence of even the lowest of the vertebrata in the inferior Silurian rocks, an 

 absence which is total, so far as can be inferred from the researches of geologists in all 

 parts of the world, gives them a true "Proiozoic" character; and this condition of things 

 was mentioned by the author as a strong reason for concluding, that the epoch in ques- 

 tion was the earliest in which animal life was developed. It was also shown that the 

 Swedish and Norwegian sections afford ample illustration of the fact, that if fucoids or 

 marine vegetables did not precede the first-formed animals, they were certainly con- 

 temporaneous with them ; thus confirming the view, that the animals found in a fossil 

 state in these protozoic rocks must have been provided with vegetable sustenance. 



The almost total absence of upper Silurian rocks in Southern and Central Sweden, 

 and in the mainland of the Baltic governments of Russia, was explained by Mr. Mur- 

 chison on the hypothesis of such tracts having undergone extensive elevatory move- 

 ments, which placed them beyond the influence of depository action during the suc- 

 ceeding period ; and he mentioned that this view is rendered highly probable by the 

 discovery of true upper Silurian rocks in the Baltic islands of Gothland, Osel, and 

 Dago, which are made up of corals and molluscous remains, similar to those of the 

 Wenlock and Ludlow rocks of the British Islands ; the whole reposing on a band of 

 limestone, which occupies exactly the same place in the geological sequence, and con- 

 tains the same fossils {Pentamerus ohlongus), as the Woolhope and Horderly limestone 

 of Siluria. This calcareous band appears therefore to be the connecting link between 

 the lower and upper Silurian rocks in Scandinavia, just as in the typical districts of our 

 own country. Beneath it appear black flags, limestones, schists and sandstones, with 

 such fossils as Trinucleus Caractaci, Asaphus Buchii, A. iyrannus, Agnostus, Sphaero- 

 nites, Orthis, and certain chambered shells, greatly resembling as a group, and often 

 specifically identical with the fossils of the same age in the British Isles ; while above 

 are many concretionary coralline limestones and calcareous flagstones and shales, 

 charged with the common upper Silurian species. 



In the district around Christiania and in the islands of its bay or fiord, these two divi- 

 sions of the Silurian system are beautifully exposed in numerous undulations and dislo- 

 cations of the strata, and they are there so bound together by zoological and mineral 

 transitions, that they constitute a very distinct natural group, in which the coralline 

 masses of the upper division are singularly analogous to the best-developed types in 

 England (the Dudley and Wenlock), and like them, are overlaid by flag-like strata. 



The author next alluded to his discovery at Christiania of an ascending succession, 

 in which the upper Silurian strata are seen to pass under great escarpments of red flag- 

 stone, sandstone, and conglomerate, which, covered by porphyry, occupy a consider- 

 able breadth of high land, and repose, as in a great basin, upon the upper Silurian 

 rocks ; and this group of rocks in Scandinavia has exactly the appearance of the old 

 red sandstone of the North of England and Scotland. The details of this succession 

 of Norwegian palaeozoic rocks will be subsequently presented to the Geological Society 

 of London, and a brief abstract of the principal facts, as explained by Mr. Murchison 

 to the last meeting of the Society of Scandinavian Naturalists, will be published in the 

 volume of the Transactions of that body. 



Mr. Murchison then proceeded to give a rapid sketch of some of the leading features 

 of Russian Palseozoic Geology, showing in the first place, that the Devonian rocks 

 there occupied a space larger than the whole area of Great Britain, and exhibit at 

 the same time the most instructive development of the system yet discovered. Re- 

 posing upon Silurian rocks, and overlaid by true carboniferous limestones, they contain 

 the same fossil fishes as are found in Scotland, and the same molluscous remains and 

 corals as the contemporaneous strata of Devonshire, the Boulonnais, and the Rhenish 

 provinces. The Devonian system Mr. Murchison considers as the earliest great store- 

 house of fishes, a few species only having been discovered in the uppermost Silurian 

 rocks. 



The surprising coincidences between the organic remains of the carboniferous lime- 

 stone of Russia and of the British Islands, and the perfect agreement between nume- 

 rous species of shells found in the Westmoreland and Yorkshire dales on the one hand, 

 and the tracts of Siberia on the other, was next adverted to as a strong proof, in addi- 

 tion to that derived from the wide spread of the species of coal-plants, that the earlier 

 epochs of the earth's history were marked by much more equable and widely diffuse! 



