MR. A. MAYFIELD ON THE MOLLUSCA OF A SUFFOLK PARISH. 349 
of the farm-houses, surrounding the homestead on two or three 
sides, and doubtless dug for the purpose of draining the land upon 
which the buildings stand. 
The district is purely agricultural, the whole of the land surface 
being either arable or pasture. There are no woods ; the largest 
collection of trees is a narrow quadrangular belt of plantation 
surrounding the Vicarage grounds. 
Such are the very adverse circumstances under which the 
molluscan fauna of Mendlesham holds its existence, affording such 
strong points of difference from those which obtain in the neighbour- 
hood of Norwich, that an account of the Snails and Slugs of the 
parish may be of interest to those who, like myself, have searched 
with scoop, sieve, and collecting box, the environs of the City of 
Gardens. 
The land Snails are chiefly the hedgerow kinds, and, as might be 
expected, there are few Slugs, even Aijriolimax agrestis being 
far from plentiful. The freshwater species are those that can best 
endure the summer droughts, such as Limncea peregra , L. trunea- 
tula , P/anorbis spirorbis, Bui linns Injpnnrum and P iridium pirn ilium. 
These species swarm in the larger ditches and ponds, and in early 
summer may be picked, by dozens, from the surface of the mud. 
The populating of these ponds is a matter full of interest. Many 
of them are entirely unconnected with any other water, and there- 
fore all the species they contain must have migrated thereto by an 
overland route. To take an instance: — a small isolated pond in 
the middle of a meadow contains L. pereyra, Plan, naut ileus, 
Plan, font amis, Velletia lacustris, Sph. lacustre, and Pis. nitidum. 
A careful search in all other water within two or three hundred 
yards of the spot fails to reveal five of these species, and two of 
them, viz., Plan, nautileus and V. lacustris, I have not found 
elsewhere in the parish. Consequently there is not much chance 
that such slow travellers as Frogs and Newts have been the means 
of transport. There are a few bushes at one end of the pond, and 
at the other the ground slopes down gradually to the edge of the 
water. It is an ideal spot for birds to alight for a drink or bath, 
and doubtless the pond owes much of its population to their agency. 
Horses and cattle, too, are often driven directly from one meadow 
to another, perhaps a considerable distance although on the same 
farm. Of course the pond has a great attraction for them, and the 
