12:4 ESMARK : MOLLUSCA OF NORWAY. 



Class II.— MOLLUSCA CONCHIFERA. 



Family CYCLADID^. 



Genus SPH^RIUM Scop. 



Subgenus CORNEOLA Clessin. 



Sphaerium corneum L. Many places around Christiania ; 

 but is not common elsewhere. Moss, Formo in Gud- 

 bransdalen ; Jarlsberg, and Tyrifjorden. 



S. draparnaldi Cless. Bergen, several localities ? (Wester- 

 lund). 



S. mamillanum West. Much more common than the pre- 

 ceding species, and goes much farther north ' Sognsvand ' 

 near Christiania, Skien, Norderhoug at Ringerige^ ' Vetle- 

 vand ' near Gausdal Sanatorium, several lakes at Tdnset 

 and Malangen, in the Amt of Tromsd. 



S. mamillanum var. clessini raihi. Shell small, in trafis- 

 verse sectio?i, heart-shaped, with prominent lines of growth, 

 greyish-horn colour, either zt'ith three narrow greyish-yellow 

 bajids, or the two lowest conflue?it ; lower margin more 

 rounded than the type, a?id the curt'e to the anterior and 

 posterior side less prominent. Cardinal teeth in the left shell 

 as in the type, cardinal tooth in the right one less curved, and 

 not thickened in the posterior pa?-t. L. 6 '5 mill., br. 5*8 

 mill., th. 4-6 mill. From ' Vetlevand,' near Gausdal 

 Sanatorium in Gudbransdalen. 



Genus CALYCULINA Cles. 



Calyculina lacustris Miill. 



C. lacustris var. steini A Schm. Rather common, but only 

 in Christiania and Christiansand Stifts. Several localities 

 near Christiania, Asker, Snarden, Jarlsberg^ Sem, Skien, 

 Drobak, and Eidsvold. 



C. parulum Cles. 



C. parulum var, martens! Cles. Bergen. 



Family UNIONID^. 

 Genus MARGARITANA Schm. 



Margaritana margaritifera L. Very common all over the 



country. 



Genus ANODONTA Cuv. 

 Anodonta cygnea L. Probably common, but very little 

 known. 



J.C, v., Oct-, I8S6. 



