GLACIERS OF MOUNT RAINIER 



a fact recently established by delicate temperature 

 measurements made on European glaciers. It is this 

 singular fact, no doubt, that explains how so many 

 minute organisms are able to flourish and propagate 

 in summer on the lower portions of many glaciers. It 

 may be of interest to digress here briefly in order to 

 speak of these little known though common forms of life. 



Several species of insects are among the regular in- 

 habitants of glaciers. Most of them belong to a very 

 low order the Springtails, or Thysanura and are 

 so minute that in spite of their dark color they escape 

 the attention of most passers-by. If one looks 

 closely, however, they may readily be observed hop- 

 ping about like miniature fleas or wriggling deftly into 

 the cavities of the snow. It seems to incommode them 

 but little if in their acrobatic jumps they occasionally 

 alight in a puddle or in a rill, for they are thickly clad 

 with furry scales that prevent them from getting wet 



just as a duck is kept dry by its greasy feathers. 

 Especially plentiful on the lower parts of the Rainier 



glaciers, and more readily recognized, are slender dark- 

 brown worms of the genus Mesenchytraeus, about I inch 

 in length. Millions and millions of them may be seen 

 on favorable days in July and August writhing on the 

 surface of the ice, evidently breeding there and feed- 

 ing on organic matter blown upon the glacier in the 

 form of dust. So essential to their existence is the 

 chill of the ice that they enter several inches, and 

 sometimes many feet below the surface on days when 

 the sun is particularly hot, reappearing late in the 

 afternoon. 



Mention also deserves to be made of that microscopic 

 plant Protococcus nivalis, which is responsible for the 

 mysterious pink or light, rose-colored patches so often 

 met with on glaciers the "red snow" of a former 

 superstition. Each patch represents a colony or cul- 

 ture comprising billions of individuals. It is probable 

 that they represent but a small fraction of the total 



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