96 J. MURRAY 



In 1907 (36) Richters published also a summary of all that was known of Ant- 

 arctic Tardigrada, including the results of the work of the German, Scottish, and 

 Swedish Expeditions (although the report on the last had not then appeared). He 

 gives a list of twenty-three species recognised, and mentions fifteen others which had 

 been imperfectly observed, but he does not in that paper discriminate between the 

 Antarctic and the sub- Antarctic species. 



The Tardigrada of the Swedish Expedition were described by Richters in 1908 (38). 

 In a table at the end of this paper he enumerates ten species from the Antarctic 

 Region proper. Adding one species collected by the Scottish Expedition and one by 

 the German, we have a total of twelve Antarctic species recognised and named, 

 besides many insufficiently studied. 



Lastly, in 1909 (40), in a short note in the Zoologischen Anzeiger, Richters 

 noted three species found in moss collected by the National Antarctic Expedition, 

 under Captain Scott, in S. Victoria Land. Only one of these was sufficiently studied, 

 \ and was found to be a new species, and described as Macrobiotus meridionalis. 



There were thus thirteen species recorded for the Antarctic. We collected only 

 four species, but ,of these three were new to the Antarctic and one was new to 

 science. 



The full list of the Antarctic species, with their relation to sub- Antarctic and 

 other regions, will be given in tabular form at the end of this paper. 



LIST OF SPECIES 



Macrobiotus arcticus, Murray. 

 M. oberhauseri, Doy6re. 

 M. polaris, sp.n., Murray. 

 Diphascon alpmum, Murray. 

 Diphascon or Macrobiotus^). 



NOTES ON THE SPECIES 



GENUS Macrobiotus, Schultze (42) 



Macrobiotus arcticus, Murray (19) (Plate XIV. Figs. 2a2f) 



Specific characters. Large : young hyaline, adult pigmented. Teeth strongly 

 curved ; gullet narrow ; pharynx shortly oval, with two short rods, the second 

 shorter, and no comma. Claws large, of the Diphascon type, one pair with nearly 

 equal claws, united for some way above the base, the other pair with a very long 

 claw springing from the back of a shorter thick one. Egg oval or round, thick- 

 shelled, studded with short rods which are embedded in a hyaline substance. Dark 

 eyes. 



