476 Geological Society. 



Fragments of roots and of the boughs of trees, divested of their 

 bark, are found at Munniwarree, Wollogong and Mulibinbak, im- 

 bedded in beds of sandstone at a higher level than the beds which 

 contain the fossil trees. Similar fragments are found spread over 

 the surface at Wolion Hill, at Holw^orthy Down, and elsewhere in 

 the colony ; it is pi'obable therefore that the bed of sandstone con- 

 taining trees in a vertical position, which is found nearly at the same 

 level above the sea at Kurrur-kurran and the other places above- 

 mentioned, is the true geological position of that ancient forest from 

 which the enormous quantities of the fragments of wood which occur 

 either spread over the surface, or imbedded in the sandstone above 

 and below the lignite, have been derived. 



The sandstones of this formation, and in this vicinity, have been 

 powerfully affected by the action of intrusive rocks ; they are tra- 

 versed, at Nobby's Island and on the coast near Newcastle, by trap 

 dykes. The author refers to the 'Voyage' of Flinders, page 131, 

 for an account of mineralized fossil wood found in Bass's Straits, at 

 Reservation Island, which is composed of granite and of schist, tra- 

 versed by granite veins and trap dykes. He also refers to the ' Tasma- 

 nian Journal,' vol. i. p. 27, for an account, by the surgeon of H.M.S. 

 Erebus, Dr. M'Cormick, of silicified wood fuund in association with 

 trap rocks in Kerguelen's Land ; and to the same volume, p. 24, for 

 an account by Dr. T. D. Hooker, assistant-surgeon to H.M.S. 

 Erebus, of fossil wood found at Macquarrie plains, in Tasmania. 



The author infers, from the present position of the fossil trees at 

 Kurrur-kurran, that the land must have been alternately depressed 

 and elevated. He makes mention in the course of his paper of two 

 beds of lignite, one above the bed of fossil trees and one below it ; 

 but he does not describe the relative position and distance of these 

 two beds. 



March 22. — A paper was read " On some Pleistocene Deposits near 

 Copford, Essex," by John Brown, Esq. 



The order of the component beds of these deposits was taken from 

 a cutting made for the Eastern Counties Railway. The lowest bed 

 noticed consists of blue clay, which the author refers to a great 

 detritic accumulation called "till," and which occurs extensively 

 over the northern portion of the county of Essex. The till varies 

 considerably in character and composition ; at the N. extremity of 

 the section which the author exhibited, it was described as consist- 

 ing of a stiff tenacious clay, but witliin a short space it changed 

 to a sandy gravel, containing fishes' teeth and corals in great abun- 

 dance : the rock fragments have been derived from basaltic and se- 

 condary beds ; the latter afforded the fossils contained in the follow- 

 ing list, for the identification of which the author states that he 

 has been indebted to Mr. J. de C. Sowerby. Serpula illium, L. ; 

 S. tetragona, L. ; <S. articulata, G. S. ; S. granulata, C. ; Tcrebratula 

 rigida, U. Ch. ; T.pisum, Ch. M. ; T. striatula, L. Ch. ; Gryphcca in- 

 curva, L. ; G. dilatata, K. C. ; Inoceramus,C.; Avicula iyicpquivalvis, L.; 

 Exogyra virgula, K. C. ; Crania striata, C. ; Pollicipes maximus, C. ; 

 Ammonites Leachii, K. C. : A. annulatus, L. : A. dentatus, G. ; A. 



