WINCKWORTH : SCHEME FOR BRITISH MARINE CENSUS. 155 



In recording it will probably be necessary to notice dead as well as 

 living species, as dead shells are often the only available evidence ; 

 on the other hand records of shells only are often unreliable, and the 

 specimens may be due to ballast or trawl rubbish. Convenient 

 symbols would be + for species recorded living, I for species recorded 

 from shells only, and : for doubtful records, e.g., a few worn valves 

 or subfossil examples. A good foundation for a census exists in the 

 collections at South Kensington, Liverpool, Edinburgh, and Dublin, 

 in the records of various Biological Associations and in private col- 

 lections. With these tabulated, we should have a good start, and 

 there would be ample scope for further records. 



In the appended table and sketch map I have given the final 

 results of much thought and many attempts. 



Helicodonta obvoluta (Miiller) in Sussex. — The most easterly record for 

 this species in Sussex seems to have escaped Mr. Beeston's notice in his interesting 

 paper on this species. In a paper on Flint Workings at Cissbury (E. H. Willett, 

 in Proc. Soc. Antiq., vol. xliii, 1879) the shell was recorded from the vallum of 

 this neoHthic camp. — R. Winckworth. {Read before the Society, May 12th, 1920). 



Pyramidula rotundata var. alba at Brislington, Somerset N.— Under 

 beech and oak leaves on a decayed tree-stump I took one specimen of P. rotitndata 

 var. alba feeding on a white fungus with type. In the same bank (a red marl soil) 

 I dug out with my stick nine hibernating Helix neinoralis. Seven of these were a 

 deep brown colour (var. castanea ?), the other two normal banded specimens. The 

 brown shells so exactly matched the soil they were buried in, that it looked a good 

 case of protective resemblance. — D. Bacchus. {Read before the Society, March 

 loth, 1920). 



Helix aspersa monstr. sinistrum near Sitting-bourne — I found a perfect 

 dead specimen of the above monstrosity in my garden on the 23rd October, 1920, 

 with the animal still inside the shell. No doubt it had been killed by a sharp frost 

 two days previously. — -H. C. Huggins. (Read before the Society, Nov. loth, 

 1920). 



Valvata macrostoma Steenbuch in West Suffolk.— In May of this year I 

 found this species in some abundance in a ditch communicating with the Little 

 Ouse, some three-quarters of a mile west of Brandon. The ditch bottom had a 

 thick deposit of vegetable mud in which Carex paludosa was growing, and it was 

 on the submerged parts of this plant and on the muddy debris that the Valvata 

 was found, whilst several caddis-cases that were collected werQ composed mainly 

 of living specimens. Associated with it were Acroloxus laciistris, Liimuva pereger, 

 L. palicstris, L. tnmcatiila, Planorbis coriieiis, P. uvibilicatus, P. vortex, P. con- 

 tort us, P. fontanus, Segmentina iiitida, Physa fontinalis, Bithynia tentaciilata, 

 B. leachii, Vivipara contecta, Valvata piscinalis, V. cristata, Sphtcriiim corneum 

 and Pisidiiun milituii. — Chas. Oldham {Read before the Society, Sept. 8th, 1920). 



