ANTARCTIC TAEDIGRADA 



On collecting Antarctic Tardigrada. The methods employed in collecting the 

 fresh-water organisms in general have been detailed in Part I. of this volume, and 

 need not be repeated here. The water-bears were collected among the vegetation in 

 the lakes, and also among moss. They came next in importance after the Rotifers, 

 but not on account of being numerous in species. They were conspicuous in the 

 lakes from the great abundance of one species (Macrobiotus arcticus), which occurred 

 in numbers comparable with those of the two Bdelloid Rotifers, Philodina gregarict 

 and Adineta grandis. 



Two species were got in the lakes. The same two occurred among moss, with 

 two others. 



Priestley collected moss on the west side of Macmurdo Sound, at the Stranded 

 Moraines. It contained three species, one of which was not known at Cape Royds 

 (M. polaris), and one species found on Ross Island (M. oberhtiuseri) did not occur at 

 the Stranded Moraines. 



All the Tardigrada were collected between 7730' and 78S.lat. No Tardigrada were 

 found among the mosses collected by Professor David about 2 degrees farther north. 



Summary of previous knoivledge. The water-bears are better known than any 

 other group of Antarctic fresh-water animals. Half a dozen papers on the subject 

 have appeared, most of them by Professor Richters. The first mention I can find of 

 an Antarctic Tardigrade is by Richters, who in 1904 (31), in his preliminary report 

 on the Antarctic Moss Fauna, described a species (Macrobiotus antarcticus) found by 

 the German " Gauss " Expedition on the Gaussberg, a hill on the Antarctic continent, 

 and just within the Antarctic Circle. This was the only truly Antarctic species 

 recorded in that paper, the other ten species being from islands in the southern ocean. 



In 1906 there appeared the report on the Tardigrada collected in the South 

 Orkneys by Bruce's Scottish Expedition [Murray (15)]. These islands are truly polar 

 in climate, although lying outside the Antarctic Circle and distant from the continent. 

 Fifteen distinct species were found, but owing to the condition of the specimens it was 

 only possible to name six of them, three of which were known and three were new. 



Richters' full report on the Tardigrada of the Gauss Expedition appeared in 1907 

 (35). It made no addition to the list of Antarctic species, though it extended the 

 list of species known from the islands of the southern ocean to seventeen. 



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