352 MR. A. MAYFIELD ON THE MOLLUSCA OF A SUFFOLK PARISH. 
CjECIlioides acicula (Mull.). Dead shells in the rejectamenta of 
one of the feeders of the Dove streamlet. Their 
natural habitat could not be far distant as the 
shells were found within a quarter of a mile from 
the source of the stream. 
Succinea putris (L. ). Occasionally on the stems and leaves of 
Phalaris arundinacea and Phragmites communis, 
by the sides of ditches. 
Carychium minimum, Miill. Very common among dead leaves in 
damp places. 
Planorbis fontanus (Lightfoot). Sparingly in ponds and ditches. 
P. nautileus (L.). Plentiful in one pond. 
P. albus (L.). On Lemna minor and Callitriche verna in ditches. 
P. spirorbis, Miill. Very common and abundant. This species 
appears to be especially capable of surviving 
droughts, being often found, with the aperture of 
its shell closed by a white epiphragm, in places 
that are dry for months. 
P. UMBiLiCATua, Miill. Not common, and of smaller size than 
usual, approaching var. rhombea. 
Bullinus hypnorum (L.). Very abundant in nearly every ditch. 
Limn t /Ea peregra (Miill.). Very common. The specimens found 
in pools and ditches where the supply of water is 
very limited, are generally more produced in the 
spire. Those in the running streams are always 
small (var. pulchella), 
L. stagnalis (L.). Abundant and of large size in one pond. 
L. truncatula (Miill.). Very common ; they may be picked from 
the surface of the mud at the bottom of ditches, 
in early summer. 
Velletia lacustris (L.). On leaves of Potamogeton nntans in 
one pond. 
Valvata cristata, Miill. Abundant in every ditch. 
Sphaerium corneum (L.). Common in the mud of moats and 
ponds. 
S. lacustre (Miill.). Not uncommon in ponds. 
Pisidium fontinale (Drap.). Very sparingly and of small size. 
P. pusillum (Gmelin). The most abundant of the bivalves. 
P. nitidum, Jen. Rather common in ditches and pools. 
