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ON THE FORAMINIFERA OF THE LONDON CLAY. 

 By Professor T. Rupert Jones, F.G.S., afd W. K. Parker, Esq. 



In 1833, T. N. Wetherell, Esq., of Higbgate, discovered several 

 Foraminif'era in some London Clay taken from a well at the Lower 

 Heath, on the south side of Hampstead; see Proceed. Geol. Soc. 

 vol. ii. 1834, p. 93, and Transact. Geol. Soc. 2 ser. vol. v. p. 131. In 

 plate ix., one of the two plates accompanying Mr. Wetherell's paper 

 in the Geol. Transactions, these Foraminifera, with other small 

 fossils from the clay, were figured by Mr. J. I)e C. Sowerby, by 

 whose help also the determination of the fossils was made. 



At page 135 of Mr. Wetherell's paper, the figured Foraminifera 

 are referred to as " Nodosaria, pi. ix. figs. 3-7 ; Articulina, figs. 8- 

 10 ; Marginulina, fig. 12 ; Rotalia, figs. 13-18 ; Cristellaria, fig. 19 ; 

 Miliola, fig. 20." Fig. 11, doubtfully referred to " Frondiculina," is 

 not a Foraminifer, but probably the cast of the palettes of a Teredo ; 

 a similar fossil is figured and thus designated by D'Archiac in the 

 Mem. Soc. Geol. Franc. We have seen, in Mr. Wetherell's collec- 

 tion, the Foraminifera from the well above-mentioned, as well as 

 others from the London Clay of Hampstead, Highgate, and Finchley. 

 We possess a large series of picked specimens collected by Mr. John 

 Purdue from the London Clay of the Copenhagen Fields, Islington, 

 when the cuttings for the Great Northern Railway were being made ; 

 also some from the London Clay of Finchley, Chelsea (bed of the 

 Thames), and Clapham ; and a very fine suite of specimens from 

 Wimbledon Common (out of the clay at about 100 feet in depth). 

 The last-mentioned series is probably a nearly complete local Fora- 

 miniferal fauna; for very many pounds of the clay were minutely 

 examined, and there are only one species, and three varieties of 

 two other species, to be added from our other gatherings from the 

 London Clay. 



With regard to the figured specimens from the well near Hamp- 

 stead, the following is our determination of the species and varieties ; 

 most of the latter, however, as well as the real species, have distinct 

 names, as is common and convenient with Foraminifera : — 



Geol. Trans. 2 ser. vol. v. pi. ix. fig. 3. Dentalina Buchi, Reuss, 

 d. g. Ges. Zeitsch. ii. pi. iii. fig. 6. The specimen, still preserved by Mr. 

 Wetherell, shows the characteristic, minute, longitudinal riblets cross- 

 ing the septal constrictions, but not seen in the figure. This is not 

 an uncommon variety in some Tertiary deposits. 



Fig. 4. Dentalina eleqans, D'Orb. Foram. Foss. Bas. Vien. pi. i. 

 fig. 52. This is a fragment of one of the manifold subvarieties or 

 individual modifications of D. communis, D'Orb., which has abundant 

 representatives in the living and fossil states. 



Fig. 5. Dentalina spinulosa, Montagu, Test. Erit. Suppl. pi. xix. 

 fig. 5, p. 86. A fragment, figured upside down. A similar fragment, 

 figured and described by Montagu, obtained by Mr. Boys from the 



