NOTES AND QUERIES. 



265 



Opercula fro:*! the Paludixa-bed at Peckham. — Dear Sir, — The accom- 

 panying figures represent some impressions which occur in the Paludina-bed at 

 Peckham, to which deposit reference has before been made in " The Geologist 

 (see vol. ii., pp. 151 and 208). Pigure 1 is the most abundant variety, and 

 is of a roundish form, with a sub-central nucleus and concentric markings. 



Opercula from the Paludina Bed, Peckham (natural size). 



Having, by the kindness of Mr. Pickering, compared this with recent 

 examples, I think there can be little doubt that it is the operculum of Paludina 

 lenta, which is present in such vast numbers in this stone. I have lately found 

 one with the homy matter preserved. 



Pigure 2, of which 1 have seen but one specimen, and that one not quite 

 perfect, resembles figure 1 in the sub-central nucleus and concentric markings; 

 but differs much from it in shape, being oblong, rounded at one end, and 

 becoming narrower (almost pointed) at the other. I imagine that this operculum 

 must have belonged to a shell with an elongated aperture. Two species of 

 Paludina occur in this bed, but all the specimens I have seen have rounded 

 mouths. 



I have not seen a figure of P. aspera ; but P. Desnoyer&ii, to which the 

 other species is considered to be related, is figured with a rounded mouth by 

 Deshayes. 



It being very difficult to obtain Paludinse with the mouth perfect, either at 

 Peckham or Dulwich, I cannot state for certain that the specimen, fig. 2, is not 

 the operculum of Paludina aspera. 



The only other univalve that I have met with in the Paludina-band is the 

 Pitharella Rickmanii, The operculum No. 2, will correspond with the 

 aperture of that shell ; but I find that the Auriculidae, Achatinidas, and 

 Lymneidse, to which families Mr. Edwards considers Pitharella is related, have 

 no opercula. 



At a recent meeting of the Geologists' Association, Mr. Pickering expressed 

 doubts as to the correctness of Mr. Edwards' views, and considered Pitharella 

 to be more nearly allied to Ampullaria. This question, however, I must leave 

 to more experienced conchologists than myself. 



While on this subject 1 should like to know whether Mr. Edwards described 

 Pitharella, after a comparison of specimens, both from the Paludina-band at 

 Peckham and Dulwich, and also from the shell-rock at the latter place. The 

 shells that I have seen from the Dulwich shell-rock differ so much (being longer 

 in proportion to their breadth) from those of the Paludina-band which occurs 

 above it, at bothPeckham and Dulwich, that I should have thought they belonged 

 to two distinct species of the same genus. 



I may add that I think some public notice should be taken of the fact that 

 the first specimen of the Peckham Pitharella was discovered by Mr. Edmund 

 Jones, in the strata at Cow-lane, Peckham, and was by him submitted to 

 several geologists (who then considered it to be Volutu denudata), some time 

 before the excavations for the main drainage were commenced. — Yours truly, 

 C. Evans. 



That Mr. Edmund Jones has not had the credit of being the original finder 

 [Supplement to the " Geologist," No. 42] 



