136 

 NEW VARIETY OF AGRIOLIMAX L^VIS FROM ORKNEY 



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



(Read before the Leeds Branch of the Conchological Sooiety, i6th Nov., 1007). 



This autumn I received from Mr. A. W. Stelfox an exceedingly 

 interesting consignment of living slugs, collected by him on the 

 mainland of Orkney. Amongst them were one or two typical speci- 

 mens of the Marsh Slug, and also one perfectly black example — 

 the first melanic form of this species I have seen or known to occur, 

 and which it is necessary should be discriminated and named. 



I therefore describe it as follows : — 



AgTiolimax lasvis var. nov. nigra Rbk. 



Animal entirely deep black, with the foot-sole paler. 



The example displayed when alive all the characteristics of the 

 species : its active and lively temperament, large shield, and long 

 neck when fully extended. 



Acanthinula lamellata (JetT. ) in Upper Airedale. — In the evcninp; of May 

 22nd of this year, along witli two friends and accompanied Iw the keeper, I visited 

 liolden Gill, a deep and narrow i^len in the hillside near Silsden. On our way up 

 the bottom of the Gill I picked up several handfuls of decaying leaves on the off 

 chance of finding something of interest on new and practically private ground. 

 There is a footpath along the top of the Gill, past a waterfall and then on to the 

 open moor, which the owner of the estate kindly allows the public to use. The 

 first species to be observed was Vertigo an/iveiiigo, followed by examples of Pupa 

 anglica, Punctitm pygiihrttm, Vitrea raJiatula and var. viridcsccnti-alha, Vitrea 

 pura, and var. nitidosa, etc. Higher up the valley, on examining a handful of 

 leaves, I picked from one sycamore leaf two full-grown examples of Acanthinula 

 lamellata, and on another leaf of the same kind one other specimen, also full 

 grown. The leaves were picked up under a half-grown sycamore tree. Owing to 

 the shortening daylight, and the density of foliage on the overhanging trees, I did 

 not spend any lime ascertaining its range, etc. I was glad to have the three 

 examples which constitute, so far as I know, the only locality for this species in 

 Upper Airedale. Several specimens were collected in Shipley Glen in 1SS7-8, but 

 since then the habitat has been destroyed by a flood, and all our endeavours 

 have not enabled us to tind it again. Owing to the kindness of the keeper, I was 

 allowed to again visit the place on Monday, August 5th, with a friend, and we 

 secured a fair number of specimens. But the wild nature of the glen was against 

 our making a thorough search in one day, to determine its distribution, though we 

 anticipate having further opportunities of doing so. During our day's search we 

 increased my May list by adding Vertigo siibstriata^ Sphyiadiuin eirciitiiliim, 

 Enconulus fulvus, Acanthinula aculeata, Vitrea rogersi, and other commoner 

 things.— Fred Booth [Read before the Society, September 11, 1907). 



