S'fRATA IN Til*; NEICHBOUHnoOD OF LONDON. 43t 



■ ' From the excellent state of preservation, In which many In excellent 

 df these shells have been found, it has been thought, that P''^^^"**^""* 

 they could hardly be regarded as fossil. , Many acknow- 

 ledged fossil shells however have undergone much less 

 changes than those of this stratum ; the original coloured 

 markings are entirely discharged, and the external surfaces 

 are deeply penetrated with a strong ferruginous stain ; the 

 inner surfaces also are considerably changed, their resplen- 

 dence being superseded, to a considerable depth, by a dead 

 whiteness, the consequence of the decomposition of this 

 part of the shell. 



' Like the fossils of most other strata this assemblage of ^5'^'^ *^*'i*'* 



° differ specife- 



shells manifests a peculiar distinctive character, A few calJy from 

 shells only, which may be placed among those which are ^^V^f ^^ ^'^'^ 

 supposed to be lost, or among those which are the inhabi- sea. 

 tauts of distant seas, are here discoverable; the greater 

 number appearing not to differ specifically, as far as their ■ 

 altered state will allow of determining, from the recent 

 shells of the neighbouring sea. 



Among those, of which no recent analogue is known, A ibe'il «»«»» 

 appears to be the terebratula, figured in Dale's History and one kaow^*'^ 

 Antiquities of Harwich, &c. tab. XI, fig. 9, p. 294, and 

 described, Phil. Trans. No. 291, p. 1578. Mr. Dale de- 

 scribes this shell as Concha longa Jussilis fasciata, and re- 

 marks, that he has not observed " either in Aldrovandus, 

 ** Rondeletius, Belonins, Gesner, Jolinson, Lister, or 

 *' Bonanus, any shell, that resembles this our fossil, unless 

 ** it is one of those figured by Lachmund, p. 43, No. 6 

 « »ad 7> the inward part resembling our fossil." The 

 shells figured. by Lachmund are undoubtedly terehratulss^ 

 but they manifest no particular agreement with this 

 fossil. 



This shell appears to be figured by Lister, ITistor, 

 Co7ichtjl. tab. 211, fg. 45, and is assumed by Gnielin, as 

 anomia spond>/Iodes. The other shells, fig. 46, of the same 

 plate, referred to by Gm«Iin as anomia psiftacea, appear to 

 be mutilated specimens of the same shell. This opinion is 

 corroborated, by the tint given by the accurate artists to the 

 whole of the shells contained in this plate agreeings, with 

 the dark colour of the Essex fossil; and by the circum- 

 stance 



