PISIDIUM ASTARTOIDES. 43 



1897-1901. Pisidmm amnicum, Kennard and B. B. Woodward, Essex Nat., vol. x, pp. 95 et seq., 

 1897 ; Proc. Malac. Soc, vol. iii, p. 202, 1899 ; Proc. Geol. Assoc, vol. xvii, pp. 217 et seq., 1901. 



1913. Pisidium amnicum, B. B. Woodward, Cat. Brit. Sp. Pisidium, p. 16, pi. i, fig. 1 ; pi. iii, fig. 1 ; 

 pis. V — ix. 



Specific Characters. — See Mon. Crag Moll., pt. ii, p. 109. 



Dimensions. — L. 9 mm. B. 12 mm. 



Distribution. — Recent : almost everywhere in England in slow rivers, canals and 

 lakes ; partially distributed in Wales and Ireland, scarce in Scotland, where it has 

 not been recorded to the north of Aberdeen ; abroad from Siberia to Naples and 

 Algeria. 



Fossil : Icenian Crag — Norivich zone : Bramerton, Thorpe near 

 Norwich, Beccles, Southwold, Bulchamp. Weyhoiirne zone : East Runton, North 

 Walsham boring. Freshwater bed : West Runton. Pleistocene beds of England : 

 Barnwell, Woodston, Grays, Cropthorne, Clacton, Stutton, Selsey (A. Bell), and 

 elsewhere. Many localities in the English Holocene.^ 



Upper Pliocene : Bligny, near Dijon. 



Pleistocene: Holland — Gorkum; Switzerland — Zurich; France— Menchecourt ; 

 Denmark;^ Roumania. Holocene : Sweden and Denmark (Nordmann). 



Remarks. — Southwold was the only Crag locality known to Wood for this 

 common British species, but it has been found since at a number of places at the 

 same horizon. It is abundant in the freshwater bed at West Runton, and occurs 

 in many of the Holocene and Pleistocene deposits of Great Britain. The specimens 

 figured by Wood were from Stutton and Grays ; the one now given is from the 

 N^orwich Crag. 



Pisidium astartoides, Sandberger. Plate I, fig. 23. 



1840. Cyclas (Pisidium) amnica, var. ?, Lyell, Phil. Mag. [3], vol. xvi, p. 364, fig. 11. 



1850. Pisidium amnicum, var. sulcatum, S. V. Wood, Mon. Crag Moll., pt. ii, p. 110, tab. xi, fig. 1 b. 



1864. Pisidium amnicum, var. sulcata, S. P. Woodward in White's History of Norfolk, 3rd. ed., p. 120. 



1882. Pisidium {Fluminina) astartoides, Sandberger, Palaeontogr., vol. xxvii, p. 96, pi. xii, fig. 1. 



1890. Pisidium astartoides, C. Eeid, Plioc. Dep. Brit., p. 230, pi. v, fig. 11. 



1897-1901. Pisidium astartoides, Kennard and B. B. Woodward, Essex Nat., vol. x, pp. 103 et seq., 



fig. 5, 1897 ; Proc. G-eol. Assoc, vol. xvii, p. 253, fig. 37, no. 5, 1901. 

 1913. Pisidium astartoides, B. B. Woodward, Cat. Brit. Sp. Pisidium, p. 27, pi. i, fig. 2 ; pi. iii, fig. 2 ; 

 pi. V, tig. 10 ; pis. x-xii. 



Specific Characters. — Shell smaller than P. amnicum, inequilateral, subcordiform, 

 ventricose, somewhat solid, ornamented by strong and rather distant concentric 



^ For complete lists of the occurrence of the different Pisidia here described in the Pleistocene 

 and Holocene deposits of Great Britain and Ireland, see Mr. B. B. Woodward's recent British 

 Museum Catalogue of the British Species of Pisidium. 



" Dr. Nordmann reports the present species from the Danish Pleistocene. Medd. Dansk geol. 

 Forening, no. 8, p. 27, figs. 2, 3, 1901. 



