110 CHAS. L. WALTON. 



greatest diameter, 13 mm. ; aperture of mouth, 11 mm. long, 



8 mm. broad. Shell thick, apex acute. 

 Paludestrina stagnalis, Baster (Hydrobia ulvee). Exceedingly abundant 



on sands, Ynys Las, Dyfi estuary ; and on stones and muddy sand at 



Borth-y-Gest, Glaslyn estuary. (C. L. W.) 

 Trivia europea, Montagu. Eare, Aberystwyth. (H. J. F.) 

 Pm"pura lapillus, Linnaeus. Abundant. (H. J. F. ; C. L. W.) 

 Nassa- reticulata, Linnaeus. Aberystwyth, not common. (H. J. F.) 

 ^olidia papillosa, Linnaeus. Aberystwyth, etc., not uncommon. 



(H. J. F. ; C. L. W.) 

 Aeolidiella augulata, Alder and Hancock. One specimen imder a stone 



very low water, Aberystwyth, February 22nd, 1913. (C. L. W.) 

 M. glauca, Alder and Hancock. Rocks below College. 

 Facelina drummondi, Thompson. Aberystwyth. (H. J. F.) 



F. coronata, Forbes and Goodsir. Not uncommon, Aberystwyth. 



(C. L. W.) 

 Doto coronata, Gmelin. Aberystwyth. (H. J. F.) 

 Archidoris tuberculata, Alder and Hancock. Gwbert, near New Quay, 



Aberystwyth, Clarach, etc. (H. J. F. ; C. L. W.) 

 Jorunna johnstoni, Alder and Hancock, Aberystwyth. (C. L. W.) 

 Polycera lessoni, D'Orbigny. Rare, Aberystwyth. (C. L. W.) 

 Acanthodoris pilosa, Miiller. Aberystwyth, rare. (C. L. W.) 

 Lamellidoris bilamellata, Linnaeus. Aberystwyth, Llannia, Gwbert, etc. 



(C. L. W.) 

 Goniodoris castanea. Alder and Hancock. One specimen, Aberystwyth, 



on Botryllus vioJaceus coating Halidrys. (C. L. W.) 



G. nodosa, Montagu. Not uncommon,. Aberystwyth, Clarach, etc. 



(C. L. W.) 

 Ancula cristata. Alder. Aberystwyth. (C. L. W.) 



Anomia ephippium, Linnaeus. Fairly common under stones. (H. J. F.) 

 Mytilus edulis, Linnaeus. Locally very abundant on shores and in 



estuaries. Small where marine conditions prevail ; large and of 



considerable commercial importance in the estuaries of Portmadoc, 



Barmouth, and Aberdovey. (C. L. W.) 

 Volsella barbata, Linnaeus. Two specimens among Sahellaria, Clarach, 



1906. One, Aberystwyth, 1913. (C. L. W.) 

 Scrobicularia plana, da Costa. In mud on the Cockle beds of the various 



estuaries. (C. L. AV.) 

 Tellina tenuis, da Costa. One living specimen among Cockles, Ynys Las, 



Dyfi estuary. (C. L. W.) 



