288 JOURNAL OF CONCHOLOGY, VOL. I5, NO. 9, MAY 1ST, I918. 



Helix pisana Miill. at Swansea. — I read Mr. J. Davy Dean's notes on 

 Helix pisana in the yis?/??/^/ of July ist, 1916, with much interest. The state- 

 rhent that Dr. Gwyn JefiVeys' attempt to establish a colony at Swansea was a 

 failure is, however, incorrect. It is true that living specimens are not now to be 

 found on the golf links at Blackpill, but a small colony still maintains itself on 

 the seaward slope of the L. & N.W. railway embankment which faces south-west. 

 The area only measures 150 yards by 5 yards now-a-days, as the sandy slope has 

 been faced up with slag and limestone slabs in recent years. I enclose three 

 living s])ecimens which I collected as recently as August 20th this year, and 

 yellow ragwort or flea-bane, small storksbill, bramble sea-holly and marram are 

 the chief plants. This is also the only locality for several miles, as far as I know, 

 for Cochlicella barbara, which is present in small numbers. Was this also intro- 

 duced accidentally at the same time as H. pisanal—W. E. Quick {Read before the 

 Society, Sept. 13th. 1916). 



Testacella maugei var. viridans Morelet at Porlock Weir in West 

 Somerset. — While planting potatoes a few days ago I turned up a fine specimen 

 of this variety. The bright apricot-coloured ventral disc contrasts strongly with the 

 bronze-green of the dorsal surface, rendering it far more conspicuous than the 

 earth-coloured type. Unfortunately the colouring was soon lost when the anim.al 

 was placed in spirit. It is, perhaps, worth mentioning that this slug was obtained 

 on ground which had been pasture until last year and that it is some distance from 

 any flower garden. There is a patch of vegetables in an adjoining field but it seems 

 very unlikely that Testacella should be introduced with these, most of which are 

 raised from seed locally. The potato patch is situated on the edge ol the cliff above 

 the Bristol Channel, close to the spot where the only known Holocene shell of T. 

 7naiiqei {vecoxAtA by Mr. A. S. Kennard) was obtained. There is no trace of the 

 deposit now ; the sea having encroached considerably in recent years has probably 

 swept it away. — Norman G. Hadden i^Read before the Society, June 13th, 1917). 



Limnaea glabra var. albida nov., and Planorbis vortex var. albida nov. 

 — It may be of interest to place on record two whitish varieties of freshwater 

 shells which appear to have hitherto escaped notice. Both are in my own collec- 

 tion, and are as follows : — IJmncea glabra var. albida, Beswick, Manchester {coll. 

 T. Rogers) ; these are exceptionally large examples of the species ; and Planorbis 

 vortex var. albida, drain near River Cam, Cambridge (coll. J. W. Jackson, Oct. 

 1912). — J. Wilfrid Jackson. 



Thread-Spinning in Physa heterostropha. — In February last I obtained a 

 number of Physa heterostropha from the Bolton Canal, between Agecroft and 

 Clifton, Lanes., and placed them for some days in a glass tank of clear water some 

 ten inches in depth. I was pleased to find that in a day or two the tank was 

 filled by fine threads, descending from the surface of the water, most of the threads 

 being used by the Physcs in ascending and descending. Though thread-spinning is 

 well known in Aplecta hypnoruin, Physa fofitinalis, and many other freshwater 

 species, I can find no reference to its occurrence with regard to P. hetej-ostropha. 

 — J. Wilfrid Jackson. 



