NOTES ON LOCAL OCCURRENCE 
OF NERITINA FLUVIATILIS. 
BY 
JOHN F. MUSHAM, LINCOLN: 
This shell is found in the vicinity of Lincoln in the River 
Witham from Stamp End lock to Bardney bridge, north side of 
river, oddly on raked out weed. 
On the under sides of large sub-merged stones, and on the 
brick work of culverts. This year the river being exceptionally low 
has given mea good opportunity to prove the above statement. 
I cannot find it in the Foss-dyke from Lincoln to Saxilby. 
They occur however plentifully in the “Main drain” emptying 
into the Foss,on West side of the Racecourse, on the submerged 
base of the brick hauling bridge crossing the above. The Foss 
side of the same bridge has none on anywhere, and the same holds 
good of the bridge higher up the Foss, connecting it with 
Skellingthorpe basin. 
The shell does not, as far as I can trace, occur in Brayford, 
although reported as there ; but there are quantities of dead ones 
on and near the North Wharf, brought with sand from the Notts. 
portion of the Trent. 
It can ke taken oddly in the Upper Witham from Brayford 
Bridge to Aubourn amongst raked out weed. 
There is a strong colony of small ones on the stonework of the 
sluice near the Lincoln Laundry and under the large stones strew- 
ing that side of the river bed. 
Higher up the river on the West side is an old brick 
culvert on which var. cerina (Colbeau) occurred this summer, This 
] believe is a new record for the County. 
