313 



and Littorina rudis. I shall here give some examples. Leda 

 pernula Müll, belongs to the variety costigera Beck; it is a large, 

 rather thin shelled form, whose posterior end is bent strongly 

 upwards and on the inner side provided with a well-developed 

 longitudinal rib, stretching from the outmost point near to the 

 umbo. Ästarte Bankftii Leach appears in the variety Warhami 

 Hancock which especially is characterized by the lengthened 

 elliptical shape of the shell; but shorter forms also occur. 

 Astarte horealis Chemn. is represented by the variety placetita 

 Mörch which has a compressed shell covered with a thick bast- 

 like periostracum. Mya truncata L. occurs in the variety ud- 

 devallensis Forbes whose shell is short, its posterior end obli- 

 quely truncate, the hind margin going forwards below; together 

 with this, more lengthened forms also occur approaching up 

 to the typical form. Saxicava arctica occurs frequently with 

 exceedingly thick shells, but it can also be thin shelled. 



The present list over East-Greenland's mollusc-fauna also 

 comprises the fossil species from the quaternary time. From 

 the Southeast-Greenland we do not know any fossiliferous 

 beaches. On my request Chr. Kruuse has during his sojourn 

 of almost a year at Angmagsalik investigated this area without 

 finding the slightest trace of such. In the Northeast-Greenland 

 the Danish expeditions of 1891 — 92 and 1900 as well as the 

 Swedish Nathorst-Expedition of 1899 have on the contrary in 

 many localities found evidence of a negative shifting of the 

 shore-line after the glacial time, both in the region around 

 Scoresby-Sound, Forsblad-Fjord and Franz Joseph-Fjord. A 

 not quite small quantity of shells from these raised beds 

 have been brought home. Peculiarly enough they contain no 

 gastropods, but only bivalves of the following species: Leda 

 pernula Müll., Yoldia (Portlandia) arctica Gray, Mytiliis edulis 

 L., Modiolaria laevigata Gray, Pecten islandicus Müll., Astarte 

 Banksii Leach, Astarte borealis Chemn., Astarte elliptica Br o^n, 



