The Dawson Leuco 



Taken in Fresno County Photo by the Author 



A TYPICAL FEEDING-GROUND: THE GRAND CIRQUE, LOOKING WEST 



What, now, does our divinity — eat? To all intents and purposes, 

 snow. Watch a company of them deploy over a snowfield, hopping 

 sedately from crest to crest of the tiny ridges, or else escalading into the 

 pits which the sun has made. They are pecking industriously at the 

 surface as they go, and accumulating — well, not snow-flakes, nor yet 

 snow-balls, but frozen insects, instead. It is marvelous what a varied 

 diet is offered to these patient gleaners of the glaciers. The warm 

 winds wafted up from the great interior valley bear moths and beetles, 

 bugs and winged ants — they know not whither; and these, succumbing 

 to the sudden cold of the Sierran heights, fall in a beneficent shower over 

 the Leuco's table. Doubtless a few predatory insects, in a more active 

 state, may be found. If it be asked what the predatory insects, in turn, 

 feed upon, I point to the black "dust" which lies scattered over the 

 surface of a June snowbank in such a uniform fashion that suspicion 

 is aroused. These tiny black specks, a score or so to the square inch, 

 are insects — of what order I cannot tell — insects not over a millimeter 

 in length and perhaps a tenth of that in thickness. Thus I saw them 

 in myriads about Mammoth Crest in 1919. What their little businesses 



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