SO 4 Geological Society. 



mentioned, and apparently adapted for that purpose. These supposed 

 gas cells are found empty, are generally of a circular form, occur in 

 groups which communicate with each other, and each cavity has in its 

 centre a small pellet of carbonaceous matter. The author establishes 

 a clear distinction between these gas cells and those above described 

 as being filled with bituminous matter ; for the anthracite of South 

 Wales contains the former, but is quite free from the latter. He also 

 states, on the authority of Mr. F. Foster, that the anthracite of South 

 Wales affords a free disengagement of inflammable gas when first 

 exposed to the air. 



A communication " On Ophiura found at Child's Hill, to the N.W. 

 of Hampstead," by Nathaniel Thomas Wetherell, Esq. F.G.S. was 

 then read. 



After noticing the rare occurrence of Ophiura, and that in England 

 they had hitherto been observed only in the chalk and the lower di- 

 vision of the oolitic series, the author states, that he discovered, in 

 1829, several specimens of a species of Ophiura in the septaria of the 

 London clay of Child's Hill j that they were associated with some of 

 the most characteristic shells of that formation ; and that he had 

 found fragments of the same Ophiura in a septarium from the High- 

 gate Archway. 



Jan. 23.— A Geological Memoir was read " On a portion of Duk- 

 hun, East Indies," by Lieut.-Col. VV. H. Sykes, F.G.S. F.L.S. &c. 



The author describes his track as bounded on the west by the range 

 of mountains usually called the Ghauts by Europeans, from a mis- 

 conception of the term Ghaut, which simply means a pass, the proper 

 name being the Syhadree ; on the north by the Mool river, on the 

 east by the Seena river ; on the south by a line drawn from the city 

 of Beejapoor to the town of Meeruj, continued up the Krishna and 

 Quina rivers to the hill fort of Wassota in the Ghauts ; comprising 

 an area of about 26,000 square miles, and lying between the paral- 

 lels of north latitude 16° 45' and 19° 27', and east longitude 73° 30' 

 and 75° 53'. 



The whole of this tract, whether at the level of the sea or at the 

 elevation of 4500 feet, is composed of distinctly stratified, horizontal, 

 alternating beds of basalt and amygdaloids, without the intervention 

 of the rocks of any other formation. Similar stratification and struc- 

 ture is instanced in Malwa, and in the Vindhya, Gawelghur, and 

 Chandore ranges of mountains. 



The Dukhun (the mean elevation of the valleys and table-land of 

 which is about 1800 feet above the sea) is described as rising very 

 abruptly by terraces from the country at its base : to the eastward it 

 declines by terraces ; but these being low, and occurring at long in- 

 tervals, excite little remark. On the top of the Ghauts there are 

 numerous spurs or ranges of mountains extending to the E. and S.E. 

 The valleys between them are either narrow, tortuous and fissure- 

 like, or wide and flat j both ends being of nearly equal width. A 

 river runs through each valley, having its source at the western end. 

 The author does not think it physically possible for the present rivers 

 to have excavated any of these vallevs. Those of a fissure-like 



