On the fossil quaternary Molliisc -Гаипа of G-reenland. 



Une of the problems which most has taken up my 

 thoughts during my work with the Greenland mollusc-fauna is 

 the question: why has the small polar-sea-mussel Yoldia arctica 

 died out in the southern West-Greenland? 



That Yoldia arctica quite has disappeared from the coast 

 of the southern West-Greenland I consider most probable. 

 In the previous lists over Greenland's mollusc-fauna by Beck, 

 Mörch and Posselt, Yoldia arctica is certainly put down as 

 a recent form from some more particularly mentioned localities 

 of the coast area colonized by Denmark, but the specimens 

 which form the basis of these statements are either fossil or 

 of a very old appearance, and they can consequently not be 

 taken as a proof of the present occurrence of the species there. 

 And it was only «fragments» which Sutherland dredged at 

 Hunde-Eiland. The where-about of the southern limit of its 

 present distribution I cannot indicate. I have myself seen recent 

 specimens taken in Murchison-Sound (between 77° — 78° N.) by 

 the late Swedish zoologist A. Oh lin, but the species is also 

 mentioned by D.Walker from Melville-Bay M . 



It is true that the animal life in the South-Greenland 



') Comp, besides my treatise: "Om Molluskerne i de hævede Lag ved 

 BülandshöfÖi" (Overs. Kgl. Danske Vidensk. Selsk. Forhandl. 1904, 

 Nr. 6) where, on p. 12 — 18 (386 — 392), I have given a survey over the 

 present distribution of Yoldia arctica. 



19* 



