Introductory remarks. 



Of the arctic countries Greenland is doubtless the one which 

 has been most thoroughly explored with regard to its acarid 

 fauna ; the merit of this is chiefly due to the Danes who have 

 brought together a very rich collection of Acari. Through the 

 courtesy of Dr. Meinert, the late director of the entomological 

 department of the Museum of Natural History in Copenhagen, this 

 collection was submitted to me and examined during my work on 

 the monograph of the arctic mites. 



Most of the localities on Greenland where mites were collected 

 are, however, situated on the westcoast, from the southern point of 

 the country as far north as to Tasiusak; on the eastcoast, on the 

 contrary, only a few localities have been explored at Scoresby 

 Sound, where Ryder's expedition made investigations in 1891 and 

 a Swedish expedition under A. G. Nathorst in 1899. 



As a consequence our information regarding the fauna of the 

 eastcoast is much more meagre than of that of the westcoast and 

 every addition to our knowledge of it is most welcome. 



The following data illustrate our present knowledge of the 

 acarid fauna of Greenland. 



In my paper on the arctic Acari (12) 70 species of Oribatidœ, 

 Trombidiidœ, Parasitidœ, Hydrachnidœ and Tyroglyphinœ were recorded 

 from the arctic region, not taking the parasitic Ixodidœ and the 

 Analgesince into consideration, nor the salt-water Halacaridœ. 



Of these not less than 40 or 59 ^*/o were recorded from Greenland ; 

 but of these only 14 have been found on the eastcoast, whereas the 

 westcoast has not less than 32 species. 9 species are common to 

 both coasts, wdiile 5 species from the eastcoast have not yet been 

 recorded from the westcoast and 23 species known to occur on the 

 westcoast have not yet been met with on the eastcoast. 



Taking these circumstances into consideration it was with eager- 

 ness that I accepted the generous offer from Mr. F. Johansen, the 

 zoologist of the expedition, to examine and report on the collection 

 of Acari made by him. 



The collection consisted of 14 glass-tubes containing Acari from 

 the following localities: 



