278 CALIFORNIA ACADEMY OF SCIENCES. 



clumps around which the sand drifts; so that the surface 

 of the sandy wash is almost as humpy as the hog-wallow 

 lands of the San Joaquin Valley in California. 



The bluff, at the foot of which we rode for many miles 

 before reaching Willow Creek, consists really of a series 

 of bluffs, each receding behind its predecessor and form- 

 ing a serrated chain extending for miles. We gen- 

 erally rode over the talus from these cliffs, and it con- 

 sisted not only of the small rocks usually to be expected 

 but also of enormous boulders. The rains are very 

 fierce sometimes in these regions. On the Grand River, 

 near Moab, I have seen large waterfalls form in a few 

 moments from the flood of water on the mesas above and 

 dash over the cliffs, tearing away the rocks and soil with 

 tremendous force. The serrated form of these cliffs is 

 probably due to the greater washing away where the con- 

 figuration of the mesa above forms channels along which 

 the drainage collects, to be poured down the cliffs in cat- 

 aracts here and there instead of one continuous sheet of 

 water. An occasional tree of Juni^perus occidentalis 

 monos'perma was sometimes seen. Fraxinus a no mala 

 grew as a shrub or small tree near the edge of canons 

 once in a while, but no other trees were to be seen. An 

 intricately branched shrubby variety of Polygala acantho- 

 clada was quite common, and Eriogonum yonesii was 

 abundant and widely distributed. When this country is 

 named at all it is called Barton's Range, which will have 

 to be noted as the habitat of many plants where the lo- 

 cality could not be more definitely given. 



Late in the afternoon we reached the head of Willow 

 Creek, a paradise in this awful desert. For some dis- 

 tance from the big spring the water flows in a continuous 

 stream, finally settling in deep pools in the rocky basin 

 of the wash. Several species of grass grew tall in this 



