1110 DR. J. SIEPHENSON ON THE OLIGOCH/ETA OF THE 



Our previous knowledge of tlie Oligochieta of Spitsbergen and 

 Bear Island is due almost entirely to TJde (17), who, in addition 

 to collections from Bea,r Island (then examined for the first time), 

 had also at his disposal a small collection from Spitsbergen, sent 

 to him by Michaelsen and tentatively named, the names having 

 already been entered in the ' Tierreich ' volume on Oligochseta (11). 



The following species are all that have been recorded : — 



From Spitsbergen : — 



L'ibmhricillas pagenstecheri (Ratz.) (originally determined 

 and entered in the Tierreich volume as L. nervosus 

 (Eisen)). 

 Fridericia leydigi (Yejd.). 

 Meseiichytrceus sp. indeterminable. 



From Bear Island : — 



Marionincij ehudensis (Clap.). 

 Lumhricillus fossaru'in (Tauber). 

 Lumbricillus henkingi Ude. 

 Enchytrceus alhidus Henle. 



The only one of tliese collected by the Oxford Expedition is 

 Enchytrceus albidus. All, as will be seen, belong to the 

 Enchj-trieidae. 



The Enchvtrseidfe have always furnished the great majority of 

 Oiip'ochssta from high latitudes, and there exists a considerable 

 number of records of species of the family fi-om Nova Zembla, 

 Northern Siberia, North Russia and Norway, Gi-eenland, Arctic; 

 Canada, and Alaslca— especially species of the genera Henlea and 

 Meseiichytrceus. Welch has in recent years (20, 21, 22) drawn 

 attention to previous I'ecords of Bnchytraeidee found actually on 

 ice and snow, and has himself examined and described a number 

 of species from high latitudes, and from snowfields and glaciers. 

 Some of these worms show a resistance to cold that can only 

 be described as marvellous. Mesenchytrceus gelidus was found 

 '• abundantly on the snowfields" ; it " also occurred on the snow 

 on the mountain slope in a dense forest of fir and hemlock," and 

 " on the snow below the ice front and outside of the lateral 

 moraines of the Nisqually glacier; . . . when placed on hard- 

 packed snow during their active period, they are able to bore 

 down through it at will ; . . the snow on which they are found 

 is not pei'manent through the entire season, but melts with the 

 coming of summer, and it therefore appears that a part of their 

 life-histoi'y must be spent on or in the ground." Mesenchytrceus 

 .solifugus var. rainierensis was "abundant on the higher snow- 

 fields and glaciers of Mt. Rainier in early summer ; it was found 

 on snowfields which seldom thaw during the summer, and they 

 ■evidently pass the entire existence, generation after generation, 

 in the snow and ice." Beddard (1) mentions that an Enchytrjeid 

 has been found frozen in a block of ice, and recovered. Mr. Elton 

 writes that he has subjected the worms which I have named 

 Enchytrceus crymodes to an experiment in which they were frozen 

 solid and that they survived. 



