364 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 4, 



and I repeat, that at the period when we published our memoir, the 

 Devonian system had not been established nor its fossils defined. At 

 the same time, as M. Tchihatcheff and his friends have not been 

 able to detect fossils in the locality where we fomid them, viz. 

 the Giant's Mountain, he can scarcely venture to pronomice defini- 

 tively upon the age of these rocks, from his having found Devonian 

 fossils in the more southern portion of the promontory, viz. on the 

 northern shore of the Gulf of Nicomedia. Until more precise re- 

 searches be made, it is not clear that both Silurian and Devonian 

 fossils may not exist in the palseozoic rocks of that region. 



The other observations of M. Tchihatcheff relate to the valley of 

 the Kizil Irmak and to the age of the red sandstone formation of the 

 eastern parts of Asia Minor. 



1°. M. Tchihatcheff states that the Valley of the Kizil Irmak, in- 

 stead of being tertiary as it is marked in Murchison's Map of Russia, 

 *' belongs to the enigmatical formation of gypsum and red sandstone 

 developed on a very large scale m Asia Minor, and which Mr. Ha- 

 milton supposes to belong to the Permian system." 



2°. M. Tchihatcheff considers this red sandstone formation to be- 

 long to the terrain nummulitique. 



I am at a loss to understand where INI. Tchihatcheff has ascer- 

 tained that I have described the Valley of the Kizil Irmak as tertiary, 

 or that I have called the red sandstone formation Permian. With 

 regard to the latter statement, it must be remembered, that when my 

 work on Asia ]\Iinor was pubhshed the very name was not known, nor 

 was it used as a geological expression until after Sir R. Murchison's 

 researches in Russia in 1844. 



And with regard to the nummulitic group, I shall be enabled to 

 show in the course of this memoir, that I was fully aware of its ex- 

 istence in this part of Asia IVIinor, and had already noticed its con- 

 nection with the red sandstone formation. 



I now proceed to lay before the Society a statement of the geolo- 

 gical observations which I made in this part of Asia IMinor, comprising 

 portions of Pontus and Galatia, commencing on the shores of the 

 Black Sea near the ancient site of Sinope, and extending in a S.E. 

 direction to Tocat, and thence in a W.S.W. direction as far as Sevri- 

 hissar on the frontiers of Phrygia. I will only observe, that as the 

 vividness of memory has been somewhat impaired by length of time, 

 I cannot attempt to fill up the lacunse of my journal so satisfactorily 

 as I might have done if undertaken at an earlier period ; and, that 

 as not many sections were observed in this part of the country showing 

 the natural superpositions of the different formations, it would be 

 useless to attempt to give a complete section of the geological features 

 of the whole district. I must therefore confine myself, with few excep- 

 tions, to describing the different formations I observed, and pointing 

 out some of the principal localities where they occur. Much subsi- 

 diary information will be found in the various papers published in the 

 Transactions of the Society by Mr. Strickland and myself, — 



1. On the Geologv of the Thracian Bosphorus, bv Mr. Strickland. 

 Vol. V. p. 385.* 



