CXU PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



here, as in Western Europe, that, prior to the appearance of the Num- 

 muHtes, a considerable deposition of sands and marls had occurred, 

 thus apparently carrying these beds up to the middle Eocene period. 

 The hard nummulitic rocks at Allahdyn, near Varna, in Bulgaria, 

 have been worn into isolated pillars, as also into cavernous exca- 

 vations, the openings of which are divided by rude pillars. So arti- 

 ficial is the appearance of these relics of a former continuous stratum 

 that they had been supposed to be the remains of some ancient 

 temple ; but the improbability of such a supposition was pointed 

 out by Col. Hamilton, of the Grenadier Guards, and is reiterated by 

 Capt. Spratt, who adduces examples of many partially formed pillars, 

 where the work of disintegration and wear has not advanced so far. 

 The explanation of this phsenomenon is by no means easy, and the 

 only analogous cases which I remember, are those of the Flower Pots 

 in Lake Huron and on the north coast of the St. Lawrence (Min- 

 gan Islands), where, however, the isolated masses, being still subject 

 to the action of the Lake and River waters, are abraded more at the 

 bottom than at the top, and have therefore assumed the form of in- 

 verted cones*. Capt. Spratt considers the pillars to be the result of 

 subaerial meteoric agencies, but I am more inclined to attribute their 

 present condition to the action of lacustrine waters, highly charged 

 with carbonic acid, an idea which Capt. Spratt seems also to have 

 had in his mind, and to have considered probable, though he adds 

 that his *' impressions on the spot were favourable for an aqueous de- 

 gradation and waste at a recent period, and in fact now in process 

 under the atmospheric inHuence," — a mode of production, let it be in 

 fairness remarked, which though not so consistent with the uniformly 

 rounded surface of the pillars, is strikingly so with the formation of 

 the nummulitic sand at the base of the pillars. It is remarkable that 

 a group, supposed to be of similar pillars, occurs submerged in Varna 

 Bay, so that, if an identity can be established between them as parts 

 of one stratum, it is probable, as Capt. Spratt suggests, that Devno 

 Valley and Varna Bay have been formed by a depression of compa- 

 ratively recent date. 



North of Varna, the lower series of limestone and marls continues 

 in a line of steep banks or cliffs to near Maugalia, where the over- 

 lying reddish sands and marls appear and form the steppe-country 

 of the Dobrudscha. These deposits are well seen at Baljik, where a 

 marly bed 150 feet thick, with many marine fossils of a small size, 

 occurs at the base and is apparently an upper member of the Varna 

 series. Foraminifera are abundant, and, in the opinion of Mr. Rupert 

 Jones, are with one exception those commonly found in shallow 

 water. A mass of white chalky-looking marl 200 feet thick, and 

 containing only casts of a small bivalve, like a Cardium, resembling 

 that in the freshwater deposits of the Dardanelles, overlies the lower 

 marine bed, nearly, but not quite conformably, and passes upwards 

 into white and greyish marls replete with freshwater shells, associated 

 sometimes with the above-mentioned Cardium, so that the conditions 



* Geol. Trans. 2 ser. vol. v. p. 93, Somewhat similar phacnomena are figured 

 and described in Lieut. Nelson's paper on the Bermudas, ibid. p. 1 20. 



