A. S. Kennard Sf B.B. Woodward — Pliocene Mollmca. 401 



IV. — On some Freshwater Mollusca from the Pliocene Deposits 

 op East Anglia. 



By A. S. Kennard, F.G.S., and B. B. Woodward, F.L.S., etc. 



NON-MARINE Mollusca are extremely rare in the Pliocene deposits 

 of this country, which fact must always be a matter of regret 

 to the Palaeontologist, since they are of the utmost importance in 

 connexion with the origin of our present fauna. Unfortunately, in 

 addition to their rarity, they are often decorticated or fragmentary, 

 whence no doubt the differences in opinion as to their correct deter- 

 mination. A re-examination of all the available material has convinced 

 us that there is still much to be done before it will be possible to 

 reach finality. In these matters so much depends on one's standpoint. 

 If one starts with the preconceived idea that the Pliocene shells must 

 be identical with the recent forms, it is easy enough to identify them, 

 even if one has to go to Japan or Greenland to find its present habitat. 

 If, on the other hand, one considers it better to study carefully the 

 results of recent work on other branches of the fauna, it is obvious 

 that different results will be arrived at. Hence we are quite prepared 

 for any differences of opinion as to the correctness of our views or the 

 wisdom of creating four new species, as we now venture to do. 



1. Limn^ea Harmeri, n.sp. 



Shell elongate, oblong-conic, thin; spire elevated, slightly turreted; 

 apex acute ; whorls 6 (or 6£ ?), convex, smooth ; suture fairly deep, 

 oval, entire ; inner lip reflected, but seemingly not spread on the 

 columella and does not conceal the umbilical chink. Height 15, 

 breadth 7 mm. ; aperture, length 6, breadth 4 mm. Pliocene — 

 Norwich Crag (Icenian) : Bramerton, Norwich. Type in the Norwich 

 Museum. 



Limncea Harmeri, n.sp. (The scale represents niillimetres.) 



This species is only represented by a single example, but there can 

 be no doubt as to its specific distinctness. It may be distinguished 

 from L. tenuis, S. Woodward {Geology of Norfolk, tab. 3, fig. 30) 

 ( = Z. palustris, Mull., of S. V. Wood, L. palustris, Miill., of Kennard 

 and Woodward, L. elocles, Say, of S. Y. Wood, and L. pingelii, Moll., 

 of S. Y. Wood), by its more pronounced suture, more convex whorls, 

 and markedly oval mouth. Though bearing a superficial resemblance 

 to some forms of L. palustris, Miill., in all probability it has no 

 affinity with it. 



decade v. — VOL. vni. — no. ix. 26 



