GEOLOGICAL SURVEY OF THE TEEEITOEIES. 



109 



gated waters leave the little lake, and flow down with considerable 

 rapidity toward the Fire-Hole, by steps or terraces; each step or ter- 

 race forms a pool with its beautiful scalloped rim, from the notched 



■1^ 



edges of which the water flows on to successive terraces. In one of the 

 streams, the channel of which is about two feet wide and one foot deep, 

 the water was filled with a plant with a yellowish-pink base, bordered 

 with a very fine green silky fringe, and these fringes, or cilia, were per- 



