299 



aary high water mark and is characterized by Myltius edulis. 

 This last formation appears as whole banks of shells on large 

 areas of the point. It also covers the greater part of the flat 

 ice-scratched rocky island Satok outside the Disko-Fjord. These 

 two different horizons remind in many respects of the con- 

 ditions in Vendsyssel». These words contain a prediction of 

 the find which now is made at Orpigsuit. 



N. Hartz' s collections in 1890 show that the arctic layers 

 are not wanting either at Orpigsuit. In a clay-brink further out, at 

 the inner end of the Orpigsuit-Fjord, Hartz found a great quantity 

 of shells «just from the niveau of the plain (which only is situated 

 a few feet above the sea) to the top of the bank (60 — 70 feet above 

 the sea)'). The shells which Hartz took home were collected at 

 a height «till 60 feet above the sea level» ^). I have looked over 

 these shells and I found the following species: Yoldia arctica 

 Gray, Leda pernula Müll., Nucula tenuis Mtg. var. expansa 

 Reeve, Cardium groenlandicum Chemn., Cardium ciliatum Fabr., 

 Tellina calcaria Chemn., Axinus flexuosus Mtg., Mya truncata 

 L. et var. ovata. This composition of the fauna suggests that 

 the clay has been deposited during the high-arctic conditions. 



On this quite small territory at Orpigsuit we see collected 

 the changing faunas of the shifting periods whose series ac- 

 cording to all probabihty is as follows. At the beginning: 

 the high-arctic fauna of the glacial time with Yoldia arctica. 

 Next: the deposits of the cold temperate period with Zirphaea 

 crispata] Yoldia has disappeared during this period. At last 

 we have outside in the fjord the present arctic fauna; the 

 Zirphaea has become extinct, but the Yoldia has not im- 

 migrated again. — Here we find an uncommonly favourable 

 occasion of studying the immigration and emigration of the 

 individual species and thus in details get to understand Green- 

 land's history in the quaternary period. 



it seems to me that we here have a task which ouaht to 



M Medd. om Grønland, XV, 1898, p. 40. 



