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Show JUEASSIO WHITE SANDSTONEâ€"CKOSS-BEDDINGL 153 simple in the extreme, and majestic by reason of their simplicity. The color of the rock is almost always gray, verging towards white. Occasionally it is a very pale cream color, and again pale red. The red becomes more common as we recede from the old shore line towards the east. But of all the features of this rock the most striking is the cross-bedding. It is hard to find a single rock-face which is not lined off with rich tracery produced by the action of weathering upon the cross-lamination. The massive cliff-fronts are etched from summit to base with a filagree as intricate and delicate as frost-work. The same phenomenon is seen in the Vermilion Cliff sandstones below, often so rich and complex that it excites constant admiration. Dr. Newberry speaks of it with enthusiasm as presented in the Triassic sandstones of New Mexico. But it is far less wonderful than the cross-bedding which the Jurassic presents at every exposure. In the Colob Terrace, south of the Markagunt, the rock weathers into many cones and pyramids, and the details produced by the action of the weather upon the cross-bedding are grotesque and often ludicrous. A journey down the Upper Kanab Canon is enlivened by ever-recurring displays of this phenomenon, presented with a profuseness and variety which extort exclamations of delight from the beholder. The Jurassic sandstone was deposited over an area which cannot fall much short of 35,000 square miles, and the average thickness exceeds 1,000 feet. The imagination is utterly baffled in the endeavor to conceive how a mass so vast and at the same time so homogeneous and intricately cross-bedded throughout its entire extent could have been accumulated. Overlying the white sandstone is a series of beds which may be called shales with some reservation, and here we find for the first time an abundance of distinctive fossils. They are clearly of Jurassic genera and species, and enable us to correlate the horizon with confidence. They belong to a well-marked formation, which is represented not only throughout the greater part of the Plateau Province, but also in Colorado, Wyoming, and Northern New Mexico. From many large areas, indeed, it has been denuded, but throughout Utah it is never wanting from those exposures where its presence could be looked for. That constancy of lithological character which is so conspicuous in |