LAND AND FRESHWATER MOLLUSCA OF SUSSEX. 167 
and placed the latter in the genus Aplexus, pointing out that in 
hypnorum the mantle has plain edges, and is not expanded over 
the shell, which has a long spire and an epidermis; while in 
JSontinalis the mantle is lobed, expanding over the shell, which has 
a short spire and no epidermis. In regarding these differences as 
specific and not generic, we have followed Turton, Forbes and 
Hanley, Gwyn Jeffreys and other authorities. 
Limnea peregra. The Wandering Mud-shell.— Common in 
ponds and ditches. 
Limnea stagnalis. The Pond Mud-shell.— Abundant every- 
where in ponds and stagnant ditches. 
Limnea auricularia. The Ear-shaped Mud-shell.—In similar 
situations, but much less common. 
Limnea palustris. The Marsh Mud-shell.— Generally dis- 
tributed, and not uncommon in the marsh dykes, and here and 
there in stagnant water. 
Limnea truncatula. The Truncate Mud-shell.—In shallow 
ditches ; fond of crawling on the half-dried mud at the sides.—B. 
Mr. Unwin has found it on the mud principally by the side of the 
Cut near Landport, where it is rather plentiful. This is the only 
locality, however, in which he has met with it. Mr. Weaver has 
noted it as a rare species in the neighbourhood of Harting. At 
Ratham, near Chichester, Mr. W. Jeffery has found it plentiful, as 
also at Lindfield. 
Limnea glabra. The Smooth Mud-shell.—Very local. In narrow 
grassy ditches at Albourne, Cowfold, and Henfield.—B. In a ditch 
near Malling.—U. Rare in the vicinity of Brighton.—M. 
Ancylus fluviatilis. The River Limpet.—On and under stones 
in the shallow parts of running water, and may be found sometimes 
on the under side of the submerged leaves of the yellow water lily, 
Nuphar lutea. 
Ancylus lacustris, vel oblongus. The Lake Limpet.—Not so 
common as the last named. Mr. Borrer has found it at Cowfold 
adhering to shells of Limnea auricularia, and at Henfield and 
Albourne on the under sides of the leaves of Nymphea albu 
and Nuphar lutea. Recorded as occurring in the vicinity of 
Lewes (U), and in the neighbourhood of Brighton (M). These 
so-called freshwater Limpets furnish another illustration of the 
fact that both salt and fresh waters have their respective repre- 
sentative forms. 
