30 proceedhitgs of the geological society. [apr. 14, 



Apeil 14, 1858. 



The following communications were read : — 



1. On the occurrence of Graphulaeia Wetheeellh in Nodules from 

 the LoiiTDON Clay and the Ceag. By N. T. Wetkeeell, Esq., 

 M.E.C.S., &c. (Communicated by the President.) 



[Abridged.] 

 Aboitt twenty-six years since, on looking over some London Claj- 

 from a well at Cohiey Hatch Lane, near MusweU Hill, I discovered 

 some curious fossils which at the time puzzled me very much. 

 Having obtained, some years after, better specimens of these fossils 

 from a well at Lower Heath, Hampstead, I submitted them to the 

 inspection of Mr. James De Carl Sowerby ; and he expressed an 

 opinion that they were fragments of the homy axis of an extinct 

 species of Pennatula, and gave me for comparison some examples of 

 the recent Pennatula phosjphorea of the British coast. In 1834 I 

 drew up a paper for the Society, on some fossils from the south side 

 of Hampstead Heath ; and in one of the plates appended to the 

 paper, some fragments of the Pennatula were figured*. In 1850 the 

 first part of the beautiful monograph of British Eossil Corals by 

 Milne-Edwards and Jules Haime was published by the Palseonto- 

 graphical Society. In this part the authors, after giving a full 

 description of the fossil, state their reasons for separating it from 

 Pennatula and forming a new genus, which they named Graphularia ; 

 the Graphularia Wether ellii, found in the London Clay at many 

 places t, and also in the Barton clay, is the only known type of the 

 genus J. 



I have for a long time considered that a great many of the calcareous 

 nodules found in the Crag have been washed out of the London 

 Clay at some former period, and that the greater number were not 

 '' coprolitic," as some geologists imagine §. Nodules of this descrip- 

 tion abound in some of the localities of the London clay, especially 

 at Highgate and its vicinity ; and I think the state in which thej^ 

 occur in the Crag || is owing principally to their having been rolled, 

 and to a chemical development of the iron. I have just made an 

 interesting discovery which tends to support my views. 



Erom the London Clay at Hampstead I have lately obtained a 

 cylindrical nodule which has clearly been formed around the horny 



^ " Observations on a well dug on the south side of Hampstead Heath." 

 Geol. Trans. 2nd Series, vol. v. part 1. p. 136. tab. 8. fig. 2 a, b. 



t Highgate ; Finchley ; Fortis Green, near Finchley ; Colney Hatch Lane ; 

 MusweU Hill ; Hornsey ; Holloway, near Copenhagen House ; Hampstead 

 Tunnel ; Haverstock Hill, near Chalk Farm ; Sheppey ; and Heme Bay. 



j Milne-Edwards and J. Haime, Monog. Brit. Foss. Corals, p. 41. pi. 7. fig. 4. 



§ I have a fusiform coprolite from the London Clay near Chalk Fai-m, an 

 inch and a quarter long, five-fourths of an inch broad, and evidently spiral 

 in structure. As this is the case, some of the nodules in the Crag may be 

 decidedly coprolitic, and derived from the London Clay ; but I do not consider 

 that, because a nodule contains phosphate of lime, it mvist of necessity be a 

 coprolite. 



II My thanks are due to Mr. Eupert Jones for some kind suggestions relating 

 to this part of the paper. 



