ESMARK : MOLLUSCA OF NORWAY. 1 23 



Christiansand, many lakes in Tdnset ; Andoen, in the Amt 



of Tromso ; Oxfjord and Hammer fest, in the Amt of Fin- 



marken. 

 P. subtruncatum Malm. Rare. Christiania, Eker, Arendal, 



and Christiansand. 

 P. milium Held. Common in Christiania, Christiansand Stift, 



the Amt of Nordland, the Amt of Tromso, and the Amt 



of Finmarken. Akersvand, in Jarlsberg ; Krodsherred, 



lakes round Gausdal Sanatorium and in Tonset, Maal- 



selvedalen, Trondenses and Tromsden. 

 P. scholtzii Cles. Not common. Gausdal and Ringebu, in 



Gudbransdalen, Tonset, Trondenses, Maalselvedalen, and 



South-Var anger. 



2nd Ord. GASTEROPODA OPERCULATA. 

 I. PULMONATA TERRESTRIA. 

 Family VALVATID^E. 

 Genus VALVATA Mlill. 

 Subgenus CINCINNA Hubner. 

 Valvata piscinalis L. Common. In the vicinity of Chris- 

 tiania, Gudbransdalen, Tonset, Jsedderen, Porsangerfjord, 

 South-Varanger ; belongs to the circumpolar species. 

 V. piscinalis var. costulata West. Ringebu in Gudbrans- 

 dalen. Alt. 47 mill., diam 4-8 mill. 



Subgenus TROPIDINA Adams. 

 V. depressa C. Pfr. Stavanger, ' Vetlevand,' near Gausdal 

 Sanatorium. Alt. 5 mill., diam. 6 mill. 



Subgenus GYRORBIS Fitz. 

 V. cristata Miill. Rare. Christiania. 



V. sibirica Middl. Bottnelv, in South-Varanger; and Saloni- 

 javre in Pasvikelven, in the Amt of Finmarken. 



Family RISSOID^. 

 Genus BYTHINIA Gray. 



Bythinia tentacula:ta L. Frognerdammen near Christiania. 



