148 



The Irish Naturalist. 



August, 



is very abundant in Lough Rea, the shell is small, rather sohd, and of a 

 purplish-grey tint. Var. lacustris and the white form, var. alhida, 

 also occur in Lough Rea. 



Limnaea palustris IMiill. — In marshes, rivers, lakes, and ditches throughout 

 the vice-county. Var. corva, of which large specimens were taken 

 in Lough Brick near Loughrea, is frequent. A peculiar form of a 

 purphsh-grey tint is abundant in Lough Rea. 



L. truncatula Miill. — Widely distributed and found in all the districts 

 visited, but is never abundant. Var. elegans was taken in a quarry 

 at Ballinasloe and in roadside pools near Loughrea. Var. alhida 

 at Kilcolgan. 



Amphipeplea glutinosa Miill. — Very rare. In the canal at Ballinasloe I 

 took a few specimens of the white form, var. alhida, of this species. I 

 have not been able to find it living elsewhere in the vice-county, but 

 it occurs as a fossil in the Portumna marl, and in a river deposit near 

 Ballinasloe. 



Planorbis albus Miill. — Generally distributed and common in all rivers, 

 lakes, and ditches. 



P. glaber Jeffreys. — Rare and very local. Living specimens taken only 

 in Lough Rea. Abundant as a fossil in the marl at Portumna Bridge. 



P. crista L. — Apparently rare, but possibly overlooked owing to its small 

 size. Taken in a pool near Portumna, large and some scalariform 

 specimens ; Lough Brick near Loughrea ; Tullaghnafrankagh Lough 

 near Ardrahan ; Lough Rea ; in the River Suck and canal near 

 Ballinasloe. Plentiful as a fossil in the Portumna marl and in the 

 Ballinasloe river deposit. 



P. carinatus Miill. — Local, but abundant where it occurs. In Lough 

 Derg, the Shannon, and all its tributaries, including the Suck, in 

 drains at PoUboy bog near Ballinasloe, also in Lough Rea and L. 

 Brick. Var. disciformis in Lough Derg near Portumna. Var. 

 alhida in Lough Derg at Portumna, and in the canal at Ballinasloe, 



P. umbilicatus Miill. — Generally distributed and common, frequenting 

 marshes and ditches, apparently not associating with P. carinatus 

 which prefers the clearer waters of rivers and lakes. Very large 

 specimens occur in a bog near Ballinasloe. Var. rhomhea in drains 

 near Portumna. 



P. vortex L. — Local and rare. In the Shannon and Lough Derg near 

 Portumna. Abundant in the River Suck, the canal and Pollboy 

 Bog near Ballinasloe. Plentiful in the Gort river. Lough Coole, and 

 Lough Cutra near Gort. Also in Lough Brick and Lough Rea. 

 Occurs as a fossil in the Portumna marl and the Ballinasloe river 

 deposit. With the exception of the above-mentioned lakes and 

 rivers in the Gort and Loughrea districts, all of which drain into 

 Galway Bay, this mollusk appears, in the southern half of Ireland, to 

 be confined to the Shannon basin. The records for other rivers in 

 southern and eastern counties all seem to be erroneous and due to 

 large forms of P. leucostoma having been mistaken for this species. 



P. leucostoma Millet ( =P. spirorhis L. Auct.). — Common, ranging over 

 the entire vice-county. It is usually found in shallow pools, drains, 



