On the Silurian (and Cambrian) Strata of the Baltic Provinces of Russia, as compared with those of Scandinavia and the British Isles

I have recently completed the first part of a memoir upon the Silurian Trilobites of the Baltic provinces of Russia, containing a special geological introduction. This work is already in the hands of Silurian geologists. But as the subject of my memoir, and more particularly its geological introduction, may be of interest to British geologists in general, I will here endeavour to develop in English the most important results of my investigations, pointing out at the same time more especially some difficulties and controverted points in the parallelization of our Silurian strata with those of Scandinavia and the British Islands. There is no map accompanying my memoir; and the reader is therein requested to refer to the geological map of the Baltic provinces of Russia, published at Dorpat in 1878 by Prof. Grewingk. In this map the Silurian part was drawn by myself. The accompanying sketch (Pl. XXIII. fig. 1). will serve the purpose of the present paper.