Localities: Sacramento River (Trask), Lea; Eagle Lake, Horn; Klamath Valley and Frazer Spring, Gabb.
I am indebted to Mr. Wm. M. Gabb, of the State Geological Survey, for notes and drawings, confirmatory of previous doubts in regard to this rare and interesting mollusk. They were taken from the living animal, and coming from a distinguished Palæontologist may be relied on as correct.
[N.B.—Through inadvertence in drawing, the shell is represented as reversed in the figure.]
Professor Whitney made some remarks on the geology of the State of Nevada, of which the following is an abstract.
Having recently received a small but very interesting collection of fossils, made in Nevada by Mr. J. E. Clayton, the examination of which has added considerably to our scanty stock of information in regard to the geology of an extensive region comprised between the meridians of 115° and 120°, and the parallels of 38° and 41°, I take this occasion to set forth, in a very concise manner, the information which I have collected, up to the present time, in regard to the age of the sedimentary formations of the regions in question.
The State of Nevada occupies a portion of the continent which, during the last few years, has received a large share of attention from the public and excited the greatest interest among scientific men; but where, up to the present time, detailed geological work has been impossible, owing to the absence of any geographical map of the State approaching even to accuracy.
The U. S. Pacific Railroad Surveys furnished no geological information whatever in regard to the territory embraced within the present area of the State of Nevada. The route from Salt Lake to Humboldt River, at Lassen’s Meadows, was hastily explored by Captain Beckwith, in May, 1854, and he was accompanied by Mr. Schiel as Geologist; but no information of any value is given in regard to the geological structure of the region traversed by the party, nor were any fossils discovered, although portions of the rocks along their route have since been proved to be prolific in organic remains.
On all the geological maps of the whole territory of the United States which have been published up to the present time, the region west of the Rocky Mountains has been so misrepresented that it is quite impossible to trace any approximation, or first hinting, at either the age or the outline of the principal formations. On these maps the region lying between the Salt Lake and the Sierra Nevada is usually left uncolored, or vaguely designated as “metamorphic” with patches of “volcanic” and “desert quaternary” scattered through it at random.[26]
The first paper or publication issued, in which any definite information in regard to the geology of Nevada was given, was that of Messrs. Meek and Engelmann, published in the Proceedings of the Philadelphia Academy of Natural Sciences, for April, 1860. This paper gives the results of the examination by Mr. Meek, of the fossils obtained by Mr. H. Engelmann, who accompanied Capt. J. H. Simpson on his explorations of 1858-59, or what is generally known as “Simpson’s Wagon Road Expedition.” As the full report of this expedition has never been published, we have no other information in regard to the geology of the region traversed by Capt. Simpson’s party than that given in the paper above alluded to. The route followed on this survey was one near the present Overland Stage Road, passing through a region then entirely uninhabited by white men, but now dotted with mining camps and even towns of considerable size—a region which has been proved to contain a large number of argentiferous veins, and where mining operations have been carried on most energetically and extensively during the last two or three years.
The localities of fossils mentioned by Messrs. Meek and Engelmann, and included within the limits of Nevada, are as follows: Long. 114° 45´, Lat 39° 45´, near what is now called Egan Cañon, fragments of Trilobites, either of Upper Silurian or Devonian Age, and “closely resembling Hamilton Group Forms:”—Long. 115° 58´, Lat. 39° 33´, and Long. 115° 36´, Lat. 39° 30´; at these two localities, situated in what are now the Eureka and White Pine Mining Districts, a “group of fossils of decided Devonian type” was found. This group consisted of Atrypa reticularis, A. aspera, or a closely allied species, a small Productus, and three new species of Spirifer. This is the most westerly point, on our territory, at which any fossils belonging to formations older than the Carboniferous have, up to the present time, been discovered, so far at least as any published record shows. Between Lon. 115° and 115° 30´ and Lat. 40° 10´ and 39° 20´, is a group or series of hills, trending nearly north and south, and made up “of light yellowish gray, more or less argillaceous and arenaceous subcrystalline limestones and slates.” From these hills fossils were collected which are referred by Mr. Meek to the Upper Carboniferous series. Most of the species were new; among them were three species of Productus, two new species of Spirifer, and another apparently identical with S. cameratus; also, Athyris subtilita and a new species of Chonetes closely allied to C. Verneuiliana; these localities are near what is now known as Ruby Valley and Fort Ruby.