332 



NOTES. 



Non-marine Mot.ltisca from the Old ]5ed of the Thames at 

 Barn Elms yvirn Mabgaijitana [Pseudunio) auricularivs (Speng.). 

 {Read \^th June, 1913.) — We received from Mr. Lawrence some small 

 masses of iron-cemented grit containing shells that had come from the 

 same deposit as the race-covered Unio auricular ms,^-gQng.,Sji\6. U.tumiduSy 

 Retz. From these masses we extracted the following species : — 



Anci/lus fluviatilis, Miill. Valvata cristata, Miill. 



Limncea pereger (Miill.). Theodoxus fluviat'dis (Linn.). 



Planorhis albus, Miill. Sphcerimn corneum (Linn.). 



P. crista (Linn.). Pisidiwn Henslowanum (Shepp.). 



P. contortus (Linn.). P. supinu7n, A. Schm. 



Bithynia tentaculata (Linn.). P. nitidum^ Jenyns. 



B. Leachii (Shepp.). P. pusillum (Gmel.), Jenyns. 



Valvata piscinalis, Miill. 



The Sphcerimn corneum resembles in form the variety moenanum met 

 with at Crayford and Erith, so that this form must have lingered on, or 

 the Barn Elms deposit is older than one would have been led to believe. 



A. S. Kennard & B. B. Woodward. 



