ROEBUCK : CENSUS AUTHENTICATIONS. 349 



Where Helicella heripensis is dominant, 



H. virgata is companion dominant, with 

 H. cantiana ~\ 



H. caperata \ sub-dominant 



H. itala J 



Where H. caperata is the dominant, 



H. virgata again is companion dominant, with 

 H. heripensis \ 



H. hispida \ sub-dominant 



Agriolii/iax agrestis J 



If. hispida occurs in each case where H. heripensis takes the sub- 

 dominant place, in which case H. virgata may be absent and 

 Agriolimax agrestis present. 



CENSUS AUTHENTICATIONS. 



By W. DENISON ROEBUCK, F.L.S., Hon. Recorder. 



Anglesey : Among the shells in the Conchological Society's Voucher Collection 

 at Manchester is Vallonia excent7'ica, a few taken on Llanfaelog Common, 

 which is new to the Census. 



Berkshire : Mr. Cecil P. Hurst has been working with much vigour and success 

 Rivar Copse, which is on the western border of this county, closely adjoining 

 Wiltshire. Here he has found Ena nioiitana in fair number, and Azeca tridens 

 in abundance along with a few of its var. crystallina, and Helicigona lapicida 

 occurs there also. Examples of all these species have been kindly presented 

 by Mr. Hurst to the Society's Voucher Collection. 



Flintshire : Amongst some shells found in this county by the Rev. T. Shank- 

 land there is a fine example of Hygromia fiisca, found loth Oct., 1890, at 

 Leet, Mold, which has been seen by Mr. J. W. Taylor, and is now in the 

 Conchological Society's Voucher Collection. It is a new county record for 

 the Census. 



Herefordshire : I am indebted to Miss Margaret A. Boycott for a supply of garden 

 slugs found at The Grange, Hereford, May 24th. They include Liviax Jlavus, 

 which is new to the Census, several half-grown examples ; Avion horlensis 

 was very abundant, small and very dark, and there was a single var. subfusca; 

 Agriolimax agrestis var. retiadata one, adult ; of Milax so^verbyi there were 

 a few typical adults, and a large number of young ones which must be put 

 down as var. nigresuns, being very dark grey, almost black, and with dark 

 footsole, and no trace of the brown pigmentation. 



Hertfordshire : Mr. Charles Oldham has sent along with other species two 

 examples of Vertigo angustior, a number of V. pyg^ncra, and of Vallonia excen- 

 trica, and one of Cacilioides acicula, from mole-hills at Wilstone, Feb., 1911. 



Kirkcudbrightshire : Mr. E. Collier has sent a few slugs from Creetown, 

 28th May, 191 2. One very minute Arion intermedins was a new record for 

 the Census ; and with it were sent two typical A. circumscripitis, and a small 

 example, very brilliant orange in colour, of A. subfuscus var. aurantiaca. 



