HOLMES.] , AMETHYST MOUNTAIN. 49 



pebbles of quartz or otlier granitic constituents found in either the sand- 

 stones or conglomerates. 



The exposures of strata in the first three or four hundred feet at the 

 base are not good, and but few of the silicifled trunks appear above the 

 covering of vegetation. At the height of 500 feet the occurrences be- 

 come very numerous, and the great size and fine state of preservation 

 of many of the trunks was a matter of much surprise. Prostrate trunks, 

 40 and 50 feet in length, are of frequent occurrence, and not a few of 

 these are as much as 5 or 6 feet in diameter. 



The standing trunks are generally rather short, the degradation of the 

 compact inclosiug strata being so slow that the brittle trunks break 

 down almost as fast as they are exposed. In many cases the roots are 

 exposed, and may be seen penetrating the now solid rock with all the 

 original ramifications. One upright trunk, of gigantic proportions, rises 

 from the inclosiug strata to the height of 12 feet. By careful meas- 

 urement it was found to be 10 feet in diameter, and as there is nothing 

 to indicate to what part of the tree the exposed section belongs, the 

 roots may be far below the surface, and we are free to imagine that 

 there is buried here a worthy predecessor of the giant Sequoias of Cali- 

 fornia. Although the trunk is hollow, and partly broken down on one 

 side, the woody structure is perfectly preserved, the grain is straight, 

 and the circles of growth distinctly marked. The bark, which still re- 

 mains on the firmer parts, is 4 inches thick, and retains perfectly the 

 original deeply-lined outer surface. Specimens of the wood and bark 

 were collected, but no microscopic examinations have been made. It is 

 clear, however, that the tree was not a conifer. The strata which in- 

 close this trunk are chiefly fine-grained greenish sandstones, indurated 

 clays, and moderately coarse conglomerates. As would naturally be ex- 

 pected, these strata contain many vegetable remains : branches, rootlets, 

 fruits, and leaves are extensively inclosed. One stratum of sandstone 

 that occupies a horizon nearly on a level with the present top of the 

 giant tree contains a great variety of the most perfectly preserved 

 leaves. Such specimens as we were able to bring away with us have 

 been submitted to Prof. Leo Lesquereux for identification. They are 

 found by him to belong to the Lower Pliocene or Upper Miocene, and 

 correspond in a number of their species with the Chalk Bluffs speci- 

 mens of Professor Whitney. They include — 



Aralia Whitneyi, 



Magnolia lanceolata, 



Laurus canariensis, 



Tilia (new sp.), 



Fraxinus (new sp.). 



• 



Diospyros (new sp.), 

 Cornus (new sp.), 

 Fteris (new sp.), 

 Alnus (new sp.), and a 

 Fern (new sp.). 



It will be observed that most of these species are new, which was also 

 the case with the collection of Professor Whitney. It is also worthy of 

 remark that none of the genera are identical with those of the Elk 

 Creek locality previously mentioned. The stratigraphical relations of 

 the two localities cannot easily be made out, as they are separated by 

 15 miles of broken country, in which the strata are obscured by igneous 

 flows and Quaternary drift. The Elk Creek strata are lower by fully 

 1,000 feet. 



4h, pth 



