srECirs or PISIDIUM. 69 



AGE DOUBTFUL. 



CAMBRIDGESHIRE. CB. 



Chatteris [Prestwich Coll., B.M. L. 23951]. 

 ESSEX, NORTH. NE. 



Copford [A. S. K. & B. B. W.] [B.M. 14862 pars & L. 6678 & 



18610] [M. P. G.] ; Ruine [B.M. L. 6680]. 

 WORCESTERSHIRE. WO. 



Defford [Prestwich Coll. : B.M. L. 23954]. 



PLEISTOCENE. 



LONDON. 2L. 



Shacklewell Lane [Prestwich Coll., B.M. L. 23976]. 

 BEDFORDSHIRE. BD. 



Biddenham [Prestwich Coll., B.M. L. 23964]. 

 CAMBRIDGESHIRE. CB. 



Barnwell [A. S. K.]. 

 ESSEX, SOUTH. SE. 



Ilford [A. S. K. & B. B. W.]. 

 HUNTINGDONSHIRE. HU. 



Woodston [C. E. Y. K.]. 

 KENT, WEST. WK. 



Swanscombe [A. S. K. & B. B. W.]. 

 MIDDLESEX. MX. 



Ponders End (Glacial) [A. S. K.]. 

 NORTHAMPTONSHIRE. NO. 



Overton Longville [Prestwich Coll., B.M. L. 23970]. 

 Si ,-SSEX, WKST. WX. 



West Wittering [A. S. K.]. 

 WORCESTERSHIRE. WO. 



Birlingham, near Pershore [A. S. K.] ; Bricklehampton, near 



Pershore [A. S. K.]. 



CROMERIAN. 



NORFOLK, EAST. EN. 



West Runtou [A. S. K.] [M. P. G.]. 



This species is so imperfectly known on the Continent that one 

 can only give the localities whence it has been personally recog- 

 nized. These, however, show that it is widely spread : they are: 

 Scandinavia [Lynge Coll.], Bavaria and Transylvania [Norman 

 Coll., B.M. 98.5.20: 22272-3; 22548-9 &* 22550-2], Lake 

 Lucerne (63-120 m.) described as P. clessini, Surbeck (168, 

 p. 482)*, River Po, also Naples and Sicily [Bellini Coll.]. 



As a fossil it has been met with in the Pleistocene (Cainpinien) 

 of Brussels [Mus. Hist. Nat. Brussels], 



* Many of Clessin's species from the deep waters of Swiss lakes probably 

 also belong to this species. 





