THE VOICE OF THE DESERT 



122 



of all plants and animals are the microscopic one-celled 

 ones, just possibly because they are supposedly the oldest 

 and have had the most time in which to colonize every- 

 w^here. Except for those which are parasitic on some spe- 

 cial animal, nearly all the protozoa of fresh water are 

 found everywhere in the world except in those parts 

 eternally frozen. Before that fact was known biological 

 specialists used to go exploring like the specialists in other 

 fields in the hope of discovering new species. In the eight- 

 een nineties, for instance, a distinguished Swiss proto- 

 zoologist came all the way to the American Far West for 

 that purpose. At first he considered his expedition not en- 

 tirely a failure because he thought that he had found just 

 one. But when he got back to Switzerland he found it there 

 also. 



To the curious who poke about as I often do in the out- 

 of-the-way places so abundant in this region where so 

 many places are still really out-of-the-way, nothing is more 

 usual than the abandoned shack, the forgotten shaft of 

 some one-man mine, or even a rather imposing collection 

 of buildings v^th pieces of machinery rusting on a hillside 

 where they were left perhaps half a century ago. They re- 

 mind us that settlers do not always settle, that populations 

 move away from as well as into sparsely occupied regions. 

 And the same thing is true of nonhuman creatures, vege- 

 table as well as animal. Throughout the West there are 

 ghost tov^Tns and towns in the process of becoming ghosts 

 as well as thriving new settlements. And there are plant 

 communities precisely analagous to both. When such com- 

 munities appear to have shrunk until they now occupy 

 only small isolated areas, the botanists call them "relict 



