80 
THE GRAND CASfON DISTRICT. 
rapidly. Just here, and for three or four miles in either direction, the Per- 
mian terrace has been obliterated. It has been beveled off by erosion and 
buried beneath the wash brought down from the foot of the Vermilion 
Cliffs to the northward. But seven miles from Pipe Spring, the Permian 
terrace springs up out of the earth, scarped by its characteristic cliff. 
Stretching northwestward it increases in altitude, becoming at last 800 to 
1,000 feet high. At its summit is seen the Shinarump conglomerate, of a 
pale brown color, and beneath are the gorgeous hues of the shales. Noth- 
ing can surpass the dense, rich, and almost cloying splendor of the red- 
brown seen in these shales. They suggest the color of old mahogany, but 
are much more luminous and quite uniform. Under them are belts of 
chocolate, slate, lavender, pale Indian red, and white. Very wonderful, too, 
is the evenness of the bedding, which is brought out in great clearness and 
sharpness by the etching of minute layers of clays holding selenite. 
Between the shales and overlying conglomerate careful scrutiny enables us 
to detect an unconformity by erosion without any unconformity of dip. As 
stated in a preceding chapter, Mr. Walcott fixed provisionally the separat- 
ing horizon between the Permian and Trias at this unconformable contact. 
Along the route the vegetation is scanty indeed. Several forms of cac- 
tus are seen looking veiy diseased and mangy, and remnants of low desert 
shrubs browsed to death by cattle. Yet, strangely enough, there is one 
plant and one alone that seems to flourish. It is the common sunflower, 
found anywhere from Maine to Arizona, and seeming indifierentto the vicis- 
situdes of climate. 
About 1 8 miles from Pipe Spring the trail leads gently down into a 
broad shallow valley known as the Wild Band pockets. The drainage from 
the fronts of the Permian Cliffs, now far to the northward, here collects into 
a gulch, which gradually deepens and becomes a tributary of Kanab Cation. 
In every stream-bed may be found many depressions which would hold 
Avater even though the sources of supply were cut off. This is as true of 
wet-weather channels as of perennial streams. After the infi-equent show- 
ers, and after the surface waters have ceased to run, the bed of the stream 
will still retain pools of water, provided the bottom of it is of a consistency 
Avhich will prevent it from filtering aAvay. To these pools the people of the 
