The Irish Land and Fresh water Molhcsca. 1 79 



IvAMELLIBRANCHIATA. 



Genus— SPHaiRIUM. 



Spliserium rivicola, Iveach. 



This species was not known to Thompson (15) as Irish, but Jeffreys (8) 

 records it from Dublin. Although I have never seen an Irish specimen, 

 I believe, from descriptions I have received, that it occurs in the Iviffey 

 at Lucan near Dublin. 



Fore;ign Distribution. — England, north and central Germany, 

 Austria, Galicia, south Russia, and France. 



Splissriuni corneum, L. 



I. II. — — V. — VII. VIII. IX. X. — XII. 



In small ponds and marshes this species is generally distributed in 

 Ireland. 



Foreign Distribution. — Great Britain, south Scandinavia, Finland, 

 Russia, Transylvania, Austria, Germany, Switzerland, Italy, Sicily, 

 France, and Spain. 



Spliserium lacustre, Mlill. 

 I. II. — IV. V. — — — — — — — 



In the north of Ireland this species appears to be absent, and in the 

 south and east it is decidedly rare. 



Foreign Distribution. — England, Wales, south Scandinavia, Fin- 

 land, Russia, Transylvania, Austria, Germany, Italy, Sicily, Corsica, 

 France, Spain, Portugal, Algiers, Siberia, and Kamschatka. 



Genus— PISIDIUM. 



Fisidium amnicum, Mlill. 

 — — — — V. VI. VII. _ — X. — XII. 



All other species of the genus Pisidium are extremely difficult to deter- 

 mine, but this, owing to its large size and distinct concentric grooves, is 

 readily recognisable. It has not been found in the south of Ireland. 



Foreign Distribution. — England, Wales, Iceland, south Scandinavia, 

 Finland, Russia, Galicia, Austria, Germany, Switzerland, Italy, Sicily, 

 France, Algiers, and Siberia. 



Pisidium globulare, West. 



The only specimens of this Fisidiu^i were taken in a small pond in a 

 wood near Mullingar, and were determined by Prof. Boettger. 

 Foreign Distribution. — England and Scandinavia. 



Pisidium. henslowianum, Shepp. 

 I. — — — V. — VII. _ — — XI. — 



Like most of the other species of Pisidium, this is found in stagnant or 

 slowly-moving waters, but it is rare, and the only Irish specimen I have 

 seen was obtained in IDonegal by Mr. R. Patterson. 



F'oreign Distribution. — Great Britain, south Scandinavia, Germany, 

 Switzerland, and P'rance. 



