INDEX. 



A.ARAU, pisolitic iron ore of, 330. 



Afton Down, Isle of Wight, section at, 200. 



Agassiz, M., on the fishes of the Wealden, 180. 



: , examination of Mr. Horner's speci- 

 mens of fishes from the environs of Bonn by, 

 474. 



Aketon, notice of carboniferous rocks within area 

 of new red sandstone near, 393. 



Aldbury, Shropshire, account of section of new 

 red sandstone near, 400. 



America, deposits in lakes of, compared to the 

 Wealden, 325. 



Ammonites, fragment of, found in the Weald clay, 

 Isle of Wight, 205. 



Amygdaloid of the Dukhun described, 423. 



' , remarkable varieties 



of, 424. 



Anticlinal lines in Kent and Surrey, 142, 143, and 

 note. 



in South Wiltshire, 244. 



in thevicinity of Bristol, 244, nofe. 



Aptychus : see Trigonellites. 



Aqueous action, degradation by, of the solid por- 

 tions of the earth, in a certain sense constant, 67. 



Araucaria, cone approaching to, found on the 

 shore of Portland Island, 349. 



Argillaceous deposits of brown coal formation in 

 the environs of Bonn described, 448. 



Arkendale and Swaledale, general account of me- 

 talliferous hills between, 94. 



Arran, observations on red sandstone systems of, 

 402. 



Axes of coal fields of Bristol Channel, not parallel, 

 57. 



Aylesbury Vale, strata of, 284. 



B. 



Babington, Mr., on trap in the Mysore referred 

 to, 429. 



Bacon-hall, near Lulworth Cove, good section of 

 the lowest Purbeck strata there, 223. 



Barbon coal-pits, section in shaft of, 76, note. 



" Bargate-stone " of Surrey, a calcareous conglo- 

 merate, 146. 



Barkin to Casterton High Fell, notice of section 

 from, 95. 



Barker, Mr., on chalk in Rutlandshire, 308, and 

 note. 



Barrowmouth, notice of new red sandstone series 

 near, 395, 396 ; of magnesian conglomerate, 

 395. 



Barytes, sulphate of, found near Caxton, 306, note. 



in the Fuller's earth of Nutfield, 141. 



Basalt of the environs of Bonn described, 443- 

 445. 



■ ■ , age of, with re- 

 ference to the trachyte, 467. 



■ , no fragments of, 



found in the brown-coal deposit, 468. 



Dukhun, varieties described, 414- 



423. 



generally diffused, 417. 



that of the Solfatarra, 417. 



■ en boules, very 



, resembles 



-, columnar, 414. 

 , remarkable 



natural pavement of, at Singhur, &c., 416. 

 — — , compact, of a 



green colour, 422. 



-, statues and 



other pieces of sculpture formed of it, 422. 



3r 



