JOURNAL OF CONCHOLOGY, VOT.. l6, NO. 8, JANUARY, I922. 



Another obscure variety is P. anglica var. gunhildce West., described in Fauna 

 Pal. Reg. Binnenconch., iii, 82, 1887, from Scarborough (Sutton). It is said to 

 have the teeth well developed but without any trace of a connecting callus between 

 the peristome and the big parietal lamella. As the peristoine is said to be " sehr 

 schwach gelippt," in this form, we rather suspect it of being merely an immaturity. 



Mr. Alfred Bell, in the Essex Naturalist, xix, pp. 183-221 and 300-302, has a 

 paper entitled " British Oysters, Past and Present," which really constitutes a 

 comprehensive monograph of the British forms of Ostrea. It is illustrated with 

 seven photographic plates, and besides discussing many already named forms, 

 describes and figures the following new ones : O. edulis var. celtica, var. estuarii 

 and var. tenbiensis, O. atlantica, 0. cantii, 0. foulnessii, O. devonensis, 0. inontagtd, 

 0. canveyensis, O. angulata erthensis and O. vertex. The paper is full of 

 interesting historical and geographical details and merits careful study. 



Mr. G. C. Robson has an important paper in the October number of the Annals 

 and Mag. Nat. Hist., pp. 401-413 on the "Anatomy and Affinities of Hypsobia 

 nosophora.'''' This mollusc, originally described by Mr. Robson in 191 5, is a 

 Japanese Paludestrinid which acts as intermediate host to the Japanese Schistosoma 

 and is, therefore, a most important factor in the study of Asiatic Schistosomiasis or 

 Bilharziasis. The author comes to the conclusion that the genus Hypsobia probably 

 represents a separate sub-family of the Paludestrinidce : the characters of the 

 alimentary canal, nervous system and genitalia are distinctly of this family, but the 

 specialised respiratory system, the kidney, the female genitalia and the spermatozoa 

 seem to separate it from any of the sub-families hitherto recognised. 



We commend the following request to members : — Helix ttemoralis Linne and 

 H. hortensis Miill. . — The writer of this note is engaged in the study of the 

 numerical relationships of the main varietal forms of these species in different 

 colonies. Me would be grateful for any information regarding the position of areas 

 (preferably within 100 miles of London) where either or both species occur in any 

 numbers. Also he would be particularly glad to hear of any " birdstones " from 

 which he could obtain the debris of broken shells of the same two species. — 

 C. Diver (Captain), 40, Pembroke Square, Kensington, W. 8. 



Helix hortensis on Thrush Stones. — In a recent note read before the 

 Society the question was raised as to whether Helix /?(?r/g«j-/.s- had been found round 

 thrush stones. When at Arbroath in June, 1920, I found this shell in large 

 numbers on stones north of the town, in fact they formed 95 per cent, of the broken 

 shell, the remainder being four per cent. H. aibtistornin and one per cent. H. 

 nemoralis. Mr. R. Standen also informs me he has found //. hortensis on thrush 

 stones in Lathkildale, Derbyshire. — A. K. Lawson (Read before the Society, 

 April 6th, 1921). 



