1^6 JOURNAL OF CONCHOLOGY. 



THE LAND AND FRESHWATER MOLLUSC A 

 OF SOUTH DEVON. 



By ERNEST D. MARQUAND, M.A. 



Among the county lists published in the last two volumes of this 

 Journal there is none for South Devon ; and, therefore, I am 

 induced to send one as a commencement, although it is obvi- 

 ously very deficient, notably in the slugs and larger bivalves. 

 To many persons it is much more gratifying to add to an 

 existing list than to compile an entirely new one, so that I feel 

 sure the present contribution will soon be materially extended 

 by those who have a wider knowledge of the mollusca of this 

 district. All the species and varieties now enumerated were 

 collected by me at odd times during 1886 and 1887. In order 

 to ascertain roughly the relative frequency of Helix neiiioralis 

 and H. hortensis in my own neighbourhood, viz., the village of 

 Alphington, a mile or two south of Exeter, 1 collected indis- 

 criminately during the early summer of the latter year about 

 two hundred and fifty full-grown living specimens, taken at 

 random during various rambles in different directions. Subse- 

 quent classification showed the following proportion : — Helix 

 nemoralis, 36 per cent. ; H. hortensis^ 64 per cent. Of the 

 nemoralis batch very nearly one-half consisted of the form 

 rubella 00300, some of the specimens having the band broad. 

 The next commonest form was castanea 00000. The var. 

 libellula was represented by only a single example, 00300. The 

 prevailing variety of H. hortetisis was the bandless lutea, with 

 its sub-varieties iniiior, subalbida^ and roseolabiata. These com- 

 posed exactly two-thirds of the lot ; the next most frequent 

 form being lutea 12345, which composed one-sixth. 



With the exception of the larger towns — Plymouth, Tor- 

 quay, Ashburton, and Kingsbridge, and the picturesque village 

 of Ivybridge — all the places mentioned in the list are situated 



J.C, vi., Oct., 1889. 



