181 LAND AND FRESH-WATER MOLLUSCA OF BUTE. 
A perusal of the foregoing List will, I think, show 
that there is every likelihood of further research 
being rewarded by the discovery of other additions 
to the Mollusca of the island. Thus several aquatic 
species —such as Spherium corneum, S. lacustre, 
Valvata piscinalis, V. cristata, Planorbis nitida, ete. 
—may yet be found to occur in one or other of the 
lochs or ditches. The Swan Mussel (Anodonta 
cygnea) may also yet be discovered in some of the 
lochs, as the conditions seem to be as favourable for 
its existence—say, in Greenan Loch—as they are in 
Lochend Loch, Edinburgh, where it is moderately - 
common. | 
It may be noted here in passing, that Planorbis 
complanatus, which Haddin, when he read his paper 
on the Bute Helicidz in 1869, recorded from Lochend 
Loch as being an addition to the Scottish Fauna, 
was previously known for more than thirty years 
to be a common species in that Loch. The second 
edition of Hxcursions illustrative of the Geology and 
Natural History of the Environs of Edinburgh, by 
William Rhind, M.R.C.S., ete., published in Edinburgh 
and London in 1836, oneeine a list of the local Land 
and Fresh-water Mollusca, which includes the species 
referred to, with the remark “Common; Lochend.” — 
It was thus recognised as a Scottish species long 
prior to Haddin’s record. | 
Though, as has been pointed out, several aquatic 
molluscs may yet be added to the fauna of Bute 
few additions to the terrestrial species now recorded 
are likely to be met with in the island. The follow- 
ing, however, may yet be observed: Arion hortensis, 
Limax flavus, Succinea elegans, Helix rwpestris, Pupa 
marginata, Bulimus obscurus, and Acme lineata. | 
Sixty-one species and varieties are recorded in the 
preceding list, and these, with one or two exceptions, 
have all been certified by Mr. John W. eels 
F.L.S., Leeds. 
