Miscellaneous Notices.
BY WILLIAM P. BLAKE,
Professor of Mineralogy, Geology, and Mining, Dept. Sci. Coll. of California.
I. NEW LOCALITY OF FOSSILS IN THE GOLD-BEARING ROCKS OF CALIFORNIA.
I have obtained specimens of Ammonites from the cut in the rocks on the line of the Central Pacific Railroad, about two miles below Colfax, and in the heart of the main gold belt of the State.
The rock is a compact argillite, somewhat altered and much discolored by the peroxydation of iron. The strata are boldly flexed and are interstratified with coarse grits and a thick bed of conglomerate, so much altered that the pebbles are homogeneously cemented.
The substance of the fossils has been removed by percolating waters, but very perfect casts of them remain and show the details of the external form, but do not permit the septæ to be seen. It is thus not possible, perhaps, to determine the specific characters; and considering, also, the absence of a typical collection and works of reference, I do not attempt a minute description, preferring to refer the specimens to a palæontologist. It may, however, be observed that the fossils are undoubtedly of the secondary period; and that they are apparently specifically identical with those from the American river, in the same vicinity, of which I sent photographs to Mr. Meek, at the Smithsonian Institution, in 1863, and afterwards noticed at one of the meetings of this Academy, in September, 1864. They are, also, apparently identical with the species found in the Bear Valley, Mariposa, slates. If this species has not been already named, I desire to connect with it the name of Mr. Spear, in whose cabinet at Georgetown, the earliest specimen was carefully preserved. I obtained one specimen at the locality, and another was presented to me by Mr. Richard Carroll, it having been saved by the quarry-men, under the impression that it was a petrified rattlesnake. It is about six inches in its longest diameter, being elliptical and evidently distorted by lateral pressure.
II. TOOTH OF THE EXTINCT ELEPHANT, PLACER COUNTY.
I have received from Mr. Baker and Mr. Thompson, through the hands of Mr. E. Tyler, all of Placer County, a single molar tooth of Elephas found in the auriferous gravel near Michigan Bluffs, thus adding another locality to the list showing the former general distribution of the ancient elephants over this coast.
III. SHARK TEETH AND OTHER MARINE REMAINS, TULARE COUNTY.
When at Ocoya or Posa Creek, in 1853, I collected a great number of shark teeth from the tops of the hills, at the base of the Sierra Nevada, on the east side of the Tulare Lake. These were described and figured in my Report to the U. S. Government. Having recently revisited that region, I found other localities, and made another collection, a part of which I now exhibit to the Academy. The following genera and species are represented: Oxyrhina plana, O. tumula, Lamna clavata, Galeocerdo productus, Prionodon antiquus, Hemipristis heteropleurus, Notidanus, (Nov. Sp.?) and Zygobates, a genus of the family of Skates, having pavement-like teeth. Vertebratæ, apparently of the whale, are abundant, and some fragments of the head. These remains are now at least twelve hundred feet above the sea, and being in unbroken horizontal strata, show a very great and general uplift of the region in comparative late times. The strata were referred to the Miocene in my Report, but I am now inclined to regard them as Post-Pliocene. It is interesting to note that these strata rest undisturbed upon granite, which is traversed by gold-bearing veins, not over five miles from the point where the fossils are found, and so low that the veins must have been covered by the sea prior to the elevation of the region.
IV. QUARRY OF GOLD-BEARING ROCK.
The Baker or Whiskey Hill Mine of Placer County, a few miles from Lincoln, presents the novelty of profitable gold mining from a quarry in the slates without any well defined quartz vein. A hill with a rounded outline is covered with rough outcrops of rusty slate, over a breadth of two hundred feet or more. A quarry at one end exposes the slate, with a great variety of colors, from white to brown and red and black, the whole of it being soft and ochraceous, and in places stained green and blue with carbonate of copper. These variegated slates are like those commonly known, among California copper prospectors, as “calico rocks,” and the ground was first located and prospected for copper.
It is evident that the formation consists of beds of iron pyrites (mundic) with a small but variable portion of copper pyrites, and that the rusty, upper portions are due to the gradual decomposition of the sulphurets above the permanent water-line, or where the atmosphere has had access. Below the water-line we may not expect to find the rusty ochrey slates. This is shown, also, at a shaft which has reached the water. Blocks of mundic, taken out of that shaft, are interstratified with talcose slate. At one point, in the bottom of the quarry, a layer of green and blue carbonate of copper is found, and this is evidently the result of a gradual concentration of the copper from the decomposed ground above. The soft slate, as quarried, is trammed to a five-stamp mill, with very coarse grates, and nearly forty tons are run through it daily. The pay is said to vary from two to twenty dollars, but the average is reported to be from five to six dollars per ton.
Mr. Stearns read the following:
Since my communication to the Academy of date July 16th last, on the Shells of Baulines Bay, additional specimens (4) of Haliotis rufescens have been found by Mr. Harford and Dr. Kellogg; also many specimens of Katherina tunicata, and one of Mopalia Hindsii; from between the umbos of very large specimens of Mytilus Californianus, collected by the same gentlemen, several specimens of Barleia? subtenuis Carp.
In addition to the above marine forms, the following species were found by the same parties in a gulch at Belvidere Ranch, not far from Capt. Morgan’s house, south side of Baulines Bay: Helix Nickliniana, H. arrosa, H. infumata, H. Columbiana (hirsute var.) and H. Vancouverensis. Also, near a small stream on the same ranch, Bythinella Binneyi, Tryon. The last named species had previously been found in this neighborhood by Rev. J. Rowell.
Prof. Blake mentioned that a tooth of a mastodon had been found about three miles from Antioch, near Monte Diablo, by Capt. Stevens.
Mr. Stearns gave an account of the Helix, its anatomy, geographical distribution, and use as an article of food and for medicinal purposes, in both ancient and modern times.
Prof. Blake stated that he had in his possession a portion of a human skull said to have been taken from a depth of 250 feet below the surface, near Columbia, in Tuolumne County.