719 
(Von Buch), Catenzpora labyrinthica (Gold.*), Favosites. Gothlan- 
 dica*;+ Favosites Petropolitana, Graptolites, &c. 
- Devonian Rocks ( Northern Zone).—By visiting Livonia and Cour- 
land some essential points of interest were added to the knowledge, 
which the authors had previously obtained of the relation and con- 
tents of the old red or Devonian series.. The central districts. of 
Courland have been, for the first tine, proved to contain rocks of 
this age charged with typical fossils, both fishes and shells. | A see; 
tion of the Diina river above Riga which exhibits some undulations 
of the strata, exposes siliceous limestones, subordinate to red and 
greenish shale; whilst the country between Riga and Dorpat is oc- 
cupied by sands and marls.. M. Pander, who now resides in, this 
district, has collected a large and instructive series of its organic 
remains, chiefly from the banks of the river Aa; and among the 
Ichthyolites which they obtained from him, the authors recognised 
remains of Coccosteus and Holoptychius similar to those previously 
collected by them in the Waldai Hills; and which Professor Agassiz 
has identified specifically with forms described by him from the old 
red ‘sandstone of Scotland. | Professor Owen has also. identified 
among teeth from the collection of M. Pander, two or more varie- 
ties of the genus Dendredus (Owen), equally characteristic of the 
old red sandstone of Scotland, one of them being indeed. undistin- 
guishable from the Dendrodus of that author, described from spe- 
cimens found at Scat’s Craig near Elgin. et 
In the marls and sands of Dérpat, Professor Asmus of the Uni- 
versity at. that place has collected and is describing certain gigantic 
bones, which were formerly supposed to belong to Saurians, but 
which, by their analogy to existing skeletons, he has shown to belong 
to fishes{. A single bone of one of these remains is nearly three feet 
long, and according to the estimate of Professor Asmus, the Ich- 
thyolite of which it is a part must have had, when entire, a length of 
not less than thirty-six feet. The union of these fishes, some of the 
species ‘of which, as above stated, are typical of the old red sand- 
stone of the British isles, with numerous. fossil shells which have 
been found to characterize the beds of the Devonian age in 
England, Belgium, and the Boulonsnais (an union was. pointed 
out last year as resulting from an examination of the provinces of 
St. Petersburgh, Novogorod, Olonetz, &c.), isnow moreamply con- 
firmed by reference to the structure of the north-western, govern- 
ments of Russia, through which the same system is spread. 
Southern Zone of Devonian Rocks or Geological Axis of Russia in 
Europe.—Previous to their visit to the central and southern regions 
of Russia, the authors believed, in common with their precursors, 
* Petrefacta Germanic. Iter Thiel. fol. Dusseldorf, 1826—1833. 
+ Lamarck, Animaux sans Vertébres, tome 2. 8vo. Paris. 
+ At the request of Mr. Murchison, Professor Asmus has prepared and 
sent to England duplicate casts of these the most remarkable and most gi- 
gantic fossil fishes ever yet discovered. One set of these has been given by 
Mr, Murchison to the British Museum, another to the Geological Society 
of London, and a third to Professor Agassiz. 
