Second Geological Survey o/Bussia in Europe. 59 



formation. In this limestone fifteen species of fossils were observed, 

 including Pentameri, Terebratulce, and Orthidce ; and it is considered 

 to be the representative of a calcareous rock which ranges to the 

 north of Dorpat and Weissenstein, and is known at Oberpahlen, &c. 

 Notwithstanding their almost perfectly horizontal position, the strata 

 in the Baltic provinces of Russia indicate most clearly a passage from 

 a lower horizon on the north to a higher on the south, where they 

 are surmounted by the Devonian system. 



In announcing a large accession of Silurian fossils to their former 

 lists, the authors advert to the labours of Professor Eichwald, 

 who after a personal examination of the coast-cliffs and of the 

 Isle of Dago, has been sedulously occupied in describing many new 

 species. They also dwell upon the important addition to their 

 knowledge of new forms contributed by Dr. Worth, the secretary 

 of the Imperial Academy of Mineralogy, — forms which they purpose 

 to figure and describe in the course of the ensuing winter; and they 

 acknowledge their obligations to Colonel Helmersen and the officers 

 of the School of Mines, for aiding them in their acquisition of fresh 

 knowledge concerning the contents of these the most ancient de- 

 posits of* the Russian empire. In their tabular list of fossils the 

 authors give the following as characteristic of, and in part peculiar 

 to, the Silurian rocks of Russia : — 



Asaphus expansus (Dalm.*), A. cornutus, Illcenus crassicauda 

 (Dalm.*), Amphyx nasutus (Dalm.*), Orthoceratites vaginatus 

 (Schloth. -j-), Lituites convolvens (Schloth.f ), Clymenia Odini 

 (Eichw.J), Terebratula Wilsoni I (Sow. in Sil. Syst.), T. sphcera 

 (Von Buch$), T. camelina (Von Buch§), Orthis anomala (Terebrat. 

 Schloth.f), O. Uralensis\n.a., O.Panderi,n.s., O.cincta (Eichw.J), 

 Leptana imbrex (Pand.,), Lepteena rugosa (Dalm.||), Spirifer bifo- 

 ratus (Terebrat. id. Schloth.), <S. lynx (Eichw.j), <S. cequirostris 

 (Terebr. Schloth.), S. porambonites (Von Buch§), Pentamerus Vogu~ 

 liens 1 , n.s., very near to P. Knightii (Sil. Syst.), Crania antiquissima, 

 nob. (Orbicula antiquissima, Eichw.j), Lingtila quadrata (Eichw.:j:), 

 (Z,. Lewisii, Sil. Syst.), Ungulites (Pand.^f), Obolus (Eichw.), 

 Sphceronites aurantium (S. citrus, His.**), Hemicosmites pyriformis 

 (Von Buch), Catenipora labyrinthica (Gold.tt), Favosites Gothlan- 

 dica [ , X\ Favosites Petropolitana, Graptolites, &c. 



Devonian Rocks ( Northern Zone). — By visiting Livonia and Cour- 

 land some essential points of interest were added to the knowledge 



* Om Palseaderna eller de sa Kallade Trilobiterna. Stockholm, 1828. 

 t Die Petrefactenkunde der Vorvvelt. 8vo. Gotha, 1820. 

 X Sur le Sylteme Silurien de l'Esthonie. 8vo. St. Petersbourg, 1840. 

 § Beitriige zur Bestimmung der Gebirgsformationen in Russland. 8vo. 

 Berlin, 1840. 



|| K. Vet. Acad. Handl. 1827. 



1[ Beitriige zurGeognosie desRussischenReiches. 4to. St. Petersburg, 1830. 

 ** Lethsea Suecica. 4to. Holmiae, 1837. 



ft Petrefacta Germanise. Iter Thiel. fol. Dusseldorf, 1826—1833. 

 XX Lamarck, Animaux sans Vertebres, tome 2. 8vo. Paris. 



1 The fossils marked (i) occur in the Ural mountains only. 



