Notices of Memoirs — Fossil Forests of Yellowstone Park. 551 

 II. — Fossil Forests op the Yellowstone Park. 



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the volcanic Tertiary beds of the Yellowstone region (Bull. U. S. 

 Geol. and Geog. Survey of the Territories, vol. v. p. 125), which are 

 stated to cover or to have covered an area of not less than 10,000 square 

 miles. The chief materials consist of volcanic fragments apparently 

 distributed by water, and now form breccias, conglomerates, and sand- 

 stones, and contain an abundance of silicified wood. Where typically 

 developed, as in the valley of the East Fork, they have a thickness 

 of 5,000 feet, and rest upon eroded surfaces of granitic and Palaeozoic 

 rocks. The lowest observed occurrence of these beds is in the 

 valley of the main Yellowstone, between the first and second canons, 

 at an elevation of about 5,000 feet above the level of the sea. They 

 appear to be destitute of animal remains, but the greater part of this 

 immense group of strata is filled with the silicified remains of a 

 multitude of forests. The roots and stems are found in situ, and 

 prostrate trunks are of frequent occurrence, besides branches, leaves, 

 and fruits. These old forests are well exposed at successive levels 

 in the 2,000 feet of strata exposed on the north face of Amethyst 

 Mountain, and from the character of the vegetation, Prof. Leo 

 Lesquereux considers the strata to belong to the Lower Pliocene or 

 Upper Miocene. In many cases the wood is completely opalized or 

 agatized, and the cavities are filled with beautiful crystals of calcite, 

 quartz, and amethyst. J. M. 



III. — Keport on the Stormberg Coal-field. By Mr. E. J. Dunn. 

 4to. pp. 36. (Solomon & Qo., Cape Town, 1878.) 



~R. DUNN describes the constituent strata of the Stormbergen 

 -at top — 1. Volcanic : lavas, tuff, agglomerate, ash-beds, 

 and amygdaloids, with volcanic bombs in sandstone, about 400 feet. 

 2. Cave-sandstone : buff-coloured, pinkish, greenish, white and 

 grey, fine-grained, thick-bedded sandstone ; about 150 feet ; with 

 fragments of Sauroid bones. 3. Eed beds : friable, red and purple, 

 arenaceous shale, and similar sandstone, mottled green, alternating 

 with grey felspathic sandstones, also conglomerate (p. 8) ; about 600 

 feet ; with Sauroid bones ; and fossil wood in the lower beds, scarce. 

 4. Coal-measures : grey and light-coloured sandstones, generally 

 felspathic, alternating with shales, in which coal-seams occur, and 

 conglomerates; about 1,000 feet; carbonized plant-remains abundant 

 in the sandstones, ferns in the shales ; fossil wood abundant ; fossil 

 bones very rare. Doleritic dykes penetrate the whole series. The 

 " Stormberg " strata, he says, continue throughout the Drackensberg 

 range, and the series is as strongly marked near Harrismith as in 

 the Stormbergen. They lie conformably on red, greenish, and grey 

 shales, with grey sandstones, rich with Dicynodont and other 

 reptilian remains. Mr. Dunn separates the latter series, as " Upper 

 Karoo Beds," from the former (as " Stormberg Beds ") ; but why 

 the whole should not remain, as heretofore, as parts of the great 

 " Karoo Formation " of A. G. Bain, is not at all clear. 



The Coal-bearing beds of the Stormberg as seen on the north 



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