312 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



plain of Serai', which is bounded on the north by a low range called 

 Kur Momedelan. On the south side the plain is bounded by a 

 range of blue and grey limestone, with slates dipping in the same 

 direction. From the plain of Serai a short descent over limestone 

 conducts to the little plain of Astajii. 



The west extremity of this plain is shut in by a low range of 

 hornblende and talc rock, which protrudes through variegated 

 marls. 



This range is crossed ; after which, it curves in a westerly direc- 

 tion, bounding the road on the north ; and finally joins the Kur 

 Momedelan, which is composed of highly coloured and altered marls. 

 The red marls are frequently converted into serpentine and jasper. 

 These beds dip at an angle of 40° to the north, and repose on a grey 

 rock of decomposing felspar and hornblende, as observed just before 

 entering the plain of Ardchek. 



In the plain of Ardchek is a small lake, the water of which is 

 brackish and disagreeable. It has no outlet ; but a few insignificant 

 streams flow into it. 



On the south this plain is bounded by an eastern prolongation of 

 the great igneous range called Warrekh Dagh ; on the north side of 

 which is an outer ridge of white limestone. The north shore of the 

 lake washes the base of the high range called Kizzuljah Dagh, the 

 jagged summits of which appear to be composed of some igneous 

 rock, beautifully variegated by the numerous beds of coloured marls 

 lying without visible order on its slopes. 



The road continues to the west along the south side of the plain 

 of Anzoub, passing the extremities of several low limestone spurs 

 from the lofty and craggy range of Warrekh Dagh. The western 

 continuation of Kizzuljah Dagh, composed of white limestone, bends 

 towards the south, and at length joins an important spur called 

 Ak Kirpi Dagh, projecting from Warrekh Dagh. A precipitous 

 descent down the escarpment of this limestone barrier conducts to 

 the plain of Van (which is about four miles broad at this point) to 

 the shore of the lake. At the distance of a mile from the lake a 

 bold rock of compact grey limestone, 400 feet in height, rises abruptly 

 from the plain, presenting a perpendicular face towards the west, 

 and extending about half a mile in length from north to south. On 

 the summit of this rock stand the Citadel and eastern wall of the City 

 of Van. The foundation blocks of the Citadel are of the same lime- 

 stone as that on which they stand ; but the stone chiefly used in the 

 construction of the more recent portion of the buildings is of soft 

 reddish volcanic breccia ; and I also observed many blocks of com- 

 minuted white shell-sand, in which is a minute species of Mytilus. 

 The last is probably derived from the shore of the Lake, or from one 

 of the Islands, and is of very recent formation. At the present day, 

 however, no mollusca inhabit the Lake of Van. 



Section from Van to Mount Ararat. Fig. 20. 



At the third mile from Van, the road touches on the shore of the 

 Lake at the "perek," or soda-basins (p. 320), and then, turning slightly 



