Collecting site

Vitträsk, Finland
note there are also several lakes and a city named Vitträsk in Södra Finland, not sure what Luther 1961 {2736} p. 14 was referencing.
latitude: 60.183334     60°11'0"N
longitude: 24.5     24°30'0"E

[Precision of location: Alexandria Digital Library (with NGA GNDB data)]
[Site Named Here by name of island, bay, strait, lake, river, or stream, etc., named in source publication]

Collected here:

Planaria torva (Müller, 1773)	1961 or earlier			Binnengewässer Ostfennoskandiens. Ausfluss des Södra Vitträsk (Purasjoki, A.L. det.).
Castrada (Castrada) armata (Fuhrmann, 1894)	Aug 26, 1950			aus Södra Vitträsk u. Lill-Harparskogträsk kommender Bach, 15º C
Strongylostoma elongatum elongatum Hofsten N, 1907	1963 or earlier			Södra Vitträsk
Mesostoma lingua (Abildgaard, 1789)	1963 or earlier			Tenala: Sodra Vitträsk, Ufervegetation u.1 juv. im Plankton (Purasjoki coll., A.L. det.)
Bothromesostoma personatum (Schmidt, 1848)	1963 or earlier			Ekträsk u. Spjutsböle träsk, Södra Vitträsk
Bothromesostoma essenii Braun, 1885	1963 or earlier			Sodra Vitträsk.
Gieysztoria infundibuliformis (Fuhrmann, 1894)	1955 or earlier			Södra Vitträsk (A.L.)