Dr. Buckland 07i Fossil Fishes in the Bagshot Sands. 387 



Extracts were also read from a letter addressed to John Taylor, 

 Esq., Treas. G.S., by Mr. Frederick Edmonds, explanatory of some 

 specimens of obsidian from the mountain of Real del Monte, Mex- 

 ico, collected by Mr. Frederick Edmonds, and presented to the 

 Society by Mr. Taylor. 



About half a mile from the ancient obsidian mines is the Cerro 

 de las Navajas, in which several passages may be observed from 

 an earthy felspathic rock to perfect obsidian. Although no good 

 section is exposed, the obsidian is stated to occur in irregular beds, 

 chiefly vertical, and Mr. Edmonds is of opinion, that it has been de- 

 rived from the fusion of the felspathic rock under pressure. The 

 collection presented to the Society's museum, contained a specimen 

 of calcareous tufF from the thermal springs of El Grande. 



A notice was next read of a specimen of "the Oar's Rock, nine 

 miles south of Little Hampton, Sussex, by Roderick Impey Mur- 

 chison, Esq., V.P.£r.S. 



The specimen consists of a calcareous grit, bearing no resemblance 

 to the Bognor rock, or other beds above the chalk, but agrees with 

 some of the beds in the green sands below that formation, or with the 

 Portland beds. Mr. Murchison's principal object in laying this no- 

 tice before the Society was to point out that the Oar's Rock is be- 

 tween the parallels of disturbance which traverse the Wealden of 

 Sussex on the north, and the Isle of Wight on the south, the inter- 

 mediate space being also traversed by the protruded chalk-outliers 

 of Portsdown Hill, north of Portsmouth, and High-down Hill near 

 Worthing, described by Mr. Martin*. Mr. Murchison, therefore, 

 inferred that the Oar's Rock may indicate the protrusion of strata 

 at that point. He noticed likewise the earthquakes so frequently 

 felt at Chichester, which is situated intermediate between Portsdown 

 Hill and Highdown HUl. 



A paper was then read, " On the discovery of Fossil Fishes in the 

 Bagshot sands at Goldworth Hill, 4 miles north of Guildford;" by 

 the Rev. William Buckland, D.D., F.G.S. 



These remains were recently obtained in cutting through the 

 summit of Goldworth Hill, on the line of the London and South- 

 ampton Railway, and their preservation is due to Mr. Sibthorpe of 

 Guildford. The only organic bodies previously discovered in the Bag- 

 shot sand are the casts of shells found near Chobham Park, and no- 

 ticed in Mr. Warburton's account of the formation.f The fossils 

 described by Dr. Buckland, were obtained from a bed of greenish 

 sand, the sixth from the top of the section ; and they consist of a 

 few imperfect casts of marine shells, and the remains of marine 

 fishes. The most numerous among the latter are the teeth of sharks, 

 and the palates and teeth of rays, similar to those which abound in 

 the London clay. One large tooth of a saw-fish, procured from the 

 same bed, affords the first well-authenticated example of the discovery, 

 in England, of the genus Pristis. In addition to these remains, three 



* Geological Memoir on part of Western Sussex, p. 93, 1828. [Or 

 Phil. Mag. and .Annals, N. S., vol. iv. p. 46.] 



"f Geological Transactions, 2ncl Series, vol. i. p. 48. 



2 C 2 



