IxXX PSOCEEBINGS OF THE GEOLOGICAL SOCIETr, 



He then proceeds to describe the Devonian rocks of the Bos- 

 phorus. These are different on the two shores, and their charac- 

 ters are given in great detail, with the localities where they occur. 

 He also notices the mines of Sangari on the European side, where 

 both copper- and iron-pyrites have been obtained ; then he refers 

 to the action of the eruptive rocks in immediate contact with 

 the clay-slates and Devonian limestone. The chief peculiarity 

 of the Asiatic rocks is the greater abundance of quartzites, which 

 are well developed in the hills behind Scutari. The fossil remains 

 are the same as those found on the Asiatic side, and, being more 

 abundant, are described in fuller detail. Proceeding to the 

 northward, it is remarkable that M. de Tchihatcheff again failed 

 to discover organic remains on the Griant's Mountain, though 

 Mr. Strickland and myself found them in great abundance in the 

 argillaceous schists near the summit. 



The locality where M. de Tchihatcheff appears to have found the 

 greatest number of fossils is along the northern shore of the Gulf 

 of Ismid, between Kartal and Pendik. This district and the 

 islands in the Sea of Marmora consist of the same formations. 

 We have then a full list of the fossils found by M. de Tchihatcheff, 

 and submitted to M. de Verneuil in 1863, as well as those brought 

 back in 1854. Prom a careful examination of thirty-eight species, 

 M. de Verneuil comes to the conclusion that they belong to the 

 Lower Devonian, with a slight admixture of Silurian forms, and 

 that consequently M. Poemer is entirely wrong in referring them 

 to the Upper Devonian ; and M. de Tchihatcheff himself brings 

 forward this fact of a small amount of Silurian forms, as Phacops 

 longicaiidatus, to prove that they belong to the lowest Devonian 

 beds, having their greatest analogy with the Rhenish beds and 

 those of the west of Prance. The remarks of M. de Verneuil 

 on these fossils will be found more fully given in the ' Bulletin 

 de la Societe Greologique de Prance,' 2nd series, vol. xxi. p. 147. 



These remarks apply principally to the fossils derived from the 

 shores of the Sea of Marmora between Kartal and Pendik, and 

 it is admitted that those which are found on the two shores of the 

 Bosphorus may be of a somewhat older age, and may possibly 

 represent the passage from the Upper Silurian to the Lower 

 Devonian. 



M. de Tchihatcheff then describes the Tertiary formation in 

 this district, which reposes immediately on the Devonian series. 

 It consists of Nummulitic deposits, having a considerable de- 

 velopment, and extending along the shore of the Black Sea as 

 far as Varna, where they have been described by Captain Spratt. 

 These are succeeded by Miocene formations, but the exact limits 

 and lines of junction are difficult to establish. Both are remark- 

 able for their sterile character and almost total want of fresh 

 water. These Miocene rocks appear to be both marine and 

 lacustrine, and are in places overlain by Diluvial or Quaternary 

 deposits, in which thin bands of lignite occur, as, for instance, near 

 the northern entrance of the Dardanelles. 



