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there are evidences of a series of numerous and complicated volcanic phenomena.

The deposits in this county, though they have been extensively worked, may be considered as almost intact, when the probable amount of gold they will yet furnish is contemplated. It is probable that the volcanic formations predominate east of the Sierra in this county—the valleys most likely containing extensive fresh water tertiary deposits. Coal has often been reported, but is probably nothing more than lignite, in limited quality, such as occurs at many points east of the Sierra.

PLUMAS COUNTY.

The auriferous slates are grandly exposed in the central portions of this county. The volcanic outflows from Lassen's Peak on the north, and Pilot Peak on the south, and the volcanic crest of the Sierra, cover the larger portion of it. The upper part of Genesee valley is marked by the occurrence of granitic rocks, the lower by metamorphic slates. In a metamorphic sandstone, exposed in a canon connecting Indian and Genesee valleys, Messrs. Brewer and King, of the geological survey, found fossils which were considered by Mr. Meek, the distinguished paleontologist, as almost certainly of Jurassic age. The locality is about four miles below Gifford's ranch, and near what is called Mormon Station. Adjacent to this locality, a belt of highly crystalline limestone, containing a few obscure fossils, occurs at the junction of the metamorphic rocks and the granite; it is probably of carboniferous age. Triassic fossils were also found at another place in the calcareous slates, between the limestone belt and the granite.

The discovery of Triassic and Jurassic fossils in the rocks of Genesee valley, and the subsequent discovery of belemnites in the slates, on the Mariposa estate, indicating a formation later than the trias, and their stratigraphical position, led to the announcement in the Journal of Science, September, 1864, by Prof. Whitney, of the fact, that a large portion of the auriferous rocks of California consist of metamorphic Triassic and Jurassic strata.

This was followed by an independent announcement by Mr. W. P. Blake to the California Academy of Sciences, in October of the same year, of the probable Jurassic or cretaceous age of the gold bearing slates of California, founded upon the indentification of a group of secondary fossils from the slates contiguous to the Pine Tree vein on the Mariposa estate.

Previously, the occurrence of gold was considered as a marked indication of Silurian or palaeozoic rocks, though the earliest labors of the survey tended to the conclusion that such was not the case.

Since the discoveries made in Mariposa county, the belt of Jurassic rocks has been traced as far north as the Stanislaus river, fossils having been found at several intermediate points; and enough is now known to establish the fact, that the great metamorphic belt flanking the Sierra, is made up of triassic and jurassic strata, with a comparatively small development of carboniferous limestone; and that the occurrence of gold in paying quantities in California seems to be confined to strata of these ages.

Lassen's Peak, at the extreme northwest corner of Plumas county, consists of an imperfect flattened cone of volcanic ashes and debris, through which project sharp ridges of trachyte, rising to a height of two thousand feet from a gently sloping plateau of gray lava. No crater remains on the summit, but they are to be seen on the tops of numerous smaller cones rising from the volcanic tables in the vicinity. Traces of glacial action are to be found on all sides of this peak, between points six and nine thousand feet in elevation. Glaciers have covered its slopes and descended towards the head-waters of the streams, the canons of which now afford such stupendous examples of denudation, they being in -places more than three thousand feet deep.

The northeastern portion of the State, as already remarked, is largely covered by lava — one almost continuous area of nearly ten thousand square miles being thus overlaid.

Mt. Shasta is an enormous volcanic mass, and forms one of the grandest objects of California scenery. It is a symmetrical cone, with steep slopes, and sharp summit, rising to an altitude of 14,442 feet. The upper six thousand feet are covered with perpetual snow. It was for a^ime supposed that this was the highest summit in California, but the explorations of the State Geological Survey, in the regions of the high Sierra, between the parallels of 35° and 39° have demonstrated the fact that there are other peaks yet higher.

In the northern counties the auriferous rocks are similar in their lithological characters to those of the metamorphic belt passing through the principal mining counties already described. No fossils have been found within the State north of 41°. The series expands to the westward, and north of the Klamath river, extending quite to the coast.

In the counties north of the great valley placer mines have been worked, and furnished in the aggregate a large amount of gold; quartz veins have also been developed here to some extent. The country is exceedingly rough, and as yet but thinly settled, much of it not being thoroughly explored. Mountains ranging from six to eight thousand feet in height are not uncommon in this region. The higher summits west of the Sacramento river are granitic, while those to the east are of volcanic origin. To the State Geological Survey we are indebted for full descriptions and accurate measurements of several high peaks situated in the Sierra Nevada range, between 35° and 39°, though the number avid great altitude of these summits had been previously noted.

The culminating point, Mount Whitney, near latitude 36J 30', is about 15,000 feet high, while within a radius of thirty miles are numerous peaks rising 14,000 feet-and, over. These are all granite, which here forms the mass of the chain, eighty miles or more in width. We have/in this portion of the range by far the grandest mountain scenery to be found in the State. Canons from three to six thousand feet deep areiiot uncommon in this region. Above an altitude of 4,000 feet evi-. derfces of previously existing glaciers on an enormous scale le are to be seen, in the frequent occurrence of large areas of polished rocks, and of moraines. Smooth surfaces are especially frequent at heights varying from 6,000 to 11,000 feet. To an elevation of 9,000 feet the slopes are covered with forests of heavy timber. Above that altitude, and to a height of 10,000 or 11,000 feet, the stunted growth of alpine species is found; while below, four thousand feet, we have the scattered forests of *>ak and pine, and the dry foot-hills that border the great San Joaquin 'valley.

The Yosemite valley lies in the granitic part of the chain. Ice and water have, no doubt, been the chief agents in the formation of this wonderfully grand and singular gorge ; though it is highly probable that other causes may have operated with these to impress upon it its peculiar configuration. .9

The high peaks near Mono Lake are of metamorphic slates belonging to the eastern flank, and are marked by more rounded outlines than the granite summits further south. Mount Dana and Castle Peak are each about 13,000 feet in. elevation—the summit of the former being readily accessible.

The water from the eastern slope of the Sierra Nevada, north of 35°, as far as the Oregon line, flows into closed valleys, or bajins without outlets to the sea. East of the Sierra Nevada, therefore, we have a long line of lakes bordering the chain. Sometimes the water sinks into the sands of the desert. Some of these interior basins or valleys lie at a high elevation, while others—like Death Valley—are known to be below the level of the sea. The water of the lakes is generally intensely saline, and the lakes themselves show evidences of quite recent changes of level. Large areas, now dry, have been formerly occupied by lakes or inland seas, which may have had their greatest developments during the existence of gigantic glaciers, the marks of which are so abundant throughout the high Sierra. But comparatively little is known of the geology of the Great Basin, it being a vast and almost unexplored desert, which is also the case with the southeastern portion of California, covering an area of about thirty thousand square miles.

Geologically, the Sierra Nevada probably includes other mountain chains, lying to the east in the Great Basin, though it is doubtless older than the Rocky Mountain chain. From geological evidence, we know that its upheaval took place before any of the Coast Ranges were formed; or, in other words, after the deposition of the Jurassic, and previous to that of the Cretaceous era.

CHAPTER VII.

ZOOLOGY.

General Plan. Mammalia: Bears—Raccoons-- Skunks—Glutton—Fisher— Marten— Weasel Otter-Cougar—Jaguar — Ocelot—Wild Cats—Wolf—Coyote — Foxes — Sea Lions and Seals -Sea Elephant—Shrews -Bats — Beaver -Marmots- Squirrels—Rats—GophersPorcupine- Hares- Elk -Deer—Antelope -Bighorn- Whales and Porpoises. Birds: ruysano Cuckoo—Woodpeckers—Eagles—Hawks—Owls—Vultures —Crows - Magpies Jays—Kingfishers Flycatchers Nighthawks—Humming Birds — Swallows —Waxwingi Thrushes Mocking Birds—Grosbeaks —Linnets—Goldfinches— Sparrows — PigeonsDoves—Cranes Herons—Hjis—Par snip —Curlews- Quail Swans- Geese Brant Ducks —Pelicans—Cormorants—Albatross - Fulmars - Petrels—Gulls — Loons - Grebes —Sea Parrot—Sea Pigeon—Murre. Reptiles : Tortoise -Turtles—Lizards -Iguanas Horned Toads- Glass Snake—Rattlesnakes—Harmless Snakes-Frogs, etc.,—Salaman' ders—Four-legged Fish. Fishes : Perch -Kingfish- Basse — Moonfish— Goldfish— Viviparous Fish - Redfish — Kelpfish — Mackerel—Bonito - Albicoro - Barracouta Flying Fish—Panther Fish Sticklebacks—Rock-Cod -Seulpin- Wolf-Eel -Gobies—Toad Fish —Lump Fish-Flat Fish—halibut Turbot—Sole-Cod—Whiting -Codling—Tom-Cod —Snake fish —salmon Trout s Fish — Smelts—Killies- Herring—AnchoviesChubs—Suckers—Conger-Eel- -Balloon Fish—Sea Horse—Pipe Fish—Sting rays —Sharks—Torpedo—Angel Fish — Stingrays — Lampreys—Worm Fish. Mollusca: Oysters—Clams-- Cat fish —Mussels. Crustacea: Crabs—Lobster—Shrimps—Cram fish.

THE ANIMALS OF CALIFORNIA.

The following is a brief systematic enumeration of the vertebrated animals of California, intended to show, as far as the allotted space will permit, how many and what sorts of creatures we have, of the four highest classes. Their scientific names are given, so that those who seek further information may find it in books which treat of them, and in which the English names are often omitted or used differently. The latter are notoriously uncertain, the same being often given to different animals, and different names to the same animal in various regions, some instances of which are here mentioned.

It would be impossible to give here even a list of the invertebrate animals, and as few of them have English names, such a list would convey no information to the general reader. No complete work on

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