STELFOX : SOME BKITLsH NON-MARINE MOLLUSCA. 43 



occurred together, in others V. cristata and V. macrostonia, whilst 

 in several only one species of the tliree was found. Some of the Lewes 

 examples are flatter in the spire than the original ones from Pevensey 

 Level. This form appears to be the V. depressa, Pfeilfer, of Clessiu ^ 

 and the var. pulchella of Westerlund. In one of the latest German 

 works'- the name V. pulchella, Studer, is used instead of V. macrostonia, 

 Steeiibuch, but Mr. Kennard tells me that Studer's name is a nomen 

 midum. (Figs. 18-21.) 



3. Paludesthina confusa (Frauenfeld), in West Sussex. 

 Tlirough the hamlet of Bury, which is .situated on the Arun not far 

 from Araberley Station, there flows a small stream. The bottom of this 

 is very muddy and the sides overgrown with various plants, which 

 are at high tides covered by the waters of the Arun backing up into 

 this tributar}'. Among this vegetation lives P. confusa, as well as in the 

 small pools remaining after the tide has subsided, along the sloping 

 banks of this and the Arun itself. In September, 1911, only a few 

 very young shells were collected in the former locality, while a single 

 example was taken by R. J. Welch in the Tnain river. In May, 1908, 

 the species was common in the tributary stream, when it was 

 discovered by Mr. C. P. Harrington and myself. In the Arun at this 

 point Neritina JluviatiUs and a stunted and eroded form of Vivipara 

 vivipara occur, while the marshes are chiefly remarkable for the 

 absence of Paludestrina Jenhinsi, one of the characteristic species of 

 those near Lewes, Eastbourne, and liye. 



4. Vertigo Moclinsiana (Dupuy), in Surrey. 

 When collecting between llaslemere and Godalming in October, 

 1907, I found a colony of this somewhat local species close to the 

 main road. The locality is not far from Witley, and is a marshy spot 

 beside the small stream which flows from Lea Park through a series 

 of ponds maiked upon the Ordnance ^lap as Hammer Ponds. On 

 a second visit in March, 1909, the shell was aiiain taken, while 

 V. antivertigo occurred with it and V. aubstriata and V. pygmcea not 

 far away. Upon my last visit in September', 1911, when I was 

 accompanied by Messrs. C. E. Wright and R. J. Welch, no trace of 

 any Vertigoes were to be seen in the locality. Perhaps the severe 

 drought had something to do with their disappearance. I may add 

 that in the stream close by a very dwarf form of Anodonta cygnea was 

 found living in 6 inches of water. The locality is one which would 

 well repay further work. 



DESCRIPTION OF PLATE II. 



Figures 18-23 are magnified 1"25 diameters ; the remainder are natural size. 

 Fig. 



1. HeliccUa Heripensis (Mab.). Devil's Dyke, near Brighton, West Sussex. 



2. ,, ,, Canterbury, East Kent. 

 S. ,, ,, Lewes, East Sussex. 



' Deutsche Excursions — Molhislien-Fmina, 1876, p. 307, fig. 167. 

 - T>ie Silsswasserfauna Deutscldands, Heft xix ; MoUusca, J. Tliiele (1909) 

 p. 29, fig. 68. 



