INTRODUCTION 



During the outward and homeward voyages of the Dan m ark- 

 Expedition in 190() and 1908 to and from N.E.Greenland the 

 botanical collector Mr. A. Lundager has procured a large series of 

 samples af surface plankton by means of using tow-nets with 

 fine-meshed silk-gauze (Millergauze No. 20). Also during the stay in 

 Danma rks Havn (Denmark Harbour), Germania Land, 76°46' N. Lat., 

 18°43' W. Long., some collections were made. 



Of late years several expeditions have crossed th(; Greenland 

 Sea and brought home collections of plankton. Therefore it was 

 not likely that the plankton samples of the Danmark Expedition 

 should give much new, especially not with regard to the sam- 

 ples taken in the open Greenland Sea east and south of the pack- 

 ice (drift-ice). The main interest must lie in the samples from the 

 pack-ice itself and from the coastal Avater inside it, and further 

 in the samples from Danmarks Havn. I Ьале consequently limited 

 my examination to the samples taken in these regions and have not 

 wasted my time by examining the other samples which would have 

 given only a feeble and chance knowledge of the plankton of the 

 open Greenland Sea, »based, as it must have been, upon material 

 from two crossings alone and both in July — August. 



It would have been of the highest value if the Expedition had taken 

 samples at regular intervals, e. g. fortnightly, during the whole time 

 of the stay in Danmarks Havn from August 1906 to July 1908, as 

 we know very little of the seasonal changes in arctic coast-plankton. 

 The only source is Vanhoffen's investigations from Karajak Fjord 

 in West Greenland, ca, 70° N. Lat., (Drygalski Expedition 1892—93), 

 and it is easily understood that a comparison with those would 

 have been much appropriate. Unfortunately the collection from 

 Danmarks Havn is very incomplete; it consists of some samples from 

 the time between June 15"^ and September 10"' 1907 and a couple 

 from July 21^* 1908 when the steamer left the harbour. There is 

 here lost a chance which, perhaps, will not come again for years. 



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