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80 we have the great "Snowy Mountains," —Los Sierra Nevada, extending almost the entire length of the state along its eastern border. These form a continuous chain, rearing their heads to a height of from 9,000 to 11,000 feet above the sea level with their bases on the west resting in the broad California valleys, and with passes over their summit ranging from 5,000 to 10,000 feet in altitude. The pass of the Southern Pacific Railroad at Truckee is low in comparison to some others, Sonora Pass in Tuolumne county being 9,500 ft. high. In this great section of California we encounter an avifauna different from the rest of the state. Here is the home of Oreortyx pictus plumferus, of Contopus borealis, of Passerella iliaca megarhyncha, of Zonotrichia leucophrys, of Junco hyemalis thurberi and of a score of others which breed on the slopes of these mountains and migrate westward into the valleys in winter. This western migration is, with many species, the only migration, while with others, such as the various Empidonaces, Tachycineta and others a southerly migration takes place after the valleys are reached in the fall.

Southern California, south of Monterey Bay and of the lower end of the Sierras, might possibly be set aside as a fourth avian section; it has characteristics which none of the others have, being close to the arid deserts of Arizona, Texas and New Mexico, but it seems to be less distinct than any of the three I have mentioned, and apparently an intermediate ground for the birds of all, thus showing a mixed bird life. No birds are more interesting to work with and to watch than the Junco; the trim little plumage, sprightly and confiding air, the neat nests and dainty eggs all have a charm. California has, as far as I am able to ascertain, five species of this genus recorded within its limits,—three resident and breeding and two casual stragglers.

The most abundant and most widely distributed form is Junto hyemalis thurberi (I). This form differs from oregonus in having (2) "the sides paler and less extensively pinkish; dorsal patch paler and more sharply defined." The description of the type is as follows: (3)."Adult male. (Type No 3072; Coll., A. V. Anthony, Wilson's Peak, Cal., May 24, E. C. Thurber, collector.) Head and neck all round slaty-black, sharply defined against the white breast and pale chestnut dorsal patch; lower parts and under tail coverts pure white; sides pale pinkish, grayish on flanks; wings and tail blackish, former with slightly hoary edgings of the primaries; three lateral ferrites white, the third with inner web broadly blackish; bill and feet flesh color."

This is the common junco of California and ranges apparently throughout the Sierras and their tributary spurs from San Diego county on the south to Mt. Lessen on the north; it undoubtedly reaches farther north still but I have no record at the present writing of it so doing. During the summer juncos may be found up as high as 10,000 feet in the Sierras, but not as a rule lower than 3,000 feet, breeding. The breeding dates vary with the altitude and eggs may be found at 4,000 feet in May and as late as July fresh eggs have been taken at 9,000 feet altitude. In the southern Sierras the latest recorded set was taken on June 12 on Mt. Wils(m (4). Three or four eggs are the usual number in a set and rarely five. The nest is practically the same as that of other species of the genus, placed on ground, though there are cases on record of nests being placed in trees and in deserted woodpeckers' holes. In the fall the birds congregate in flocks and move westward, through the foothill regions into the valleys. Some winter in the mountain valleys at varying altitudes, while large numbers work down into the valley region of Central California. Thurber's Junco is a common resident in the Laguna Mts. of Lower California.

Junco kyemalis oregonus is found in the typical form in Oregon during the summer and may possibly extend southward into the California Coast Range, but the most of the juncos breeding in the northern part of California and in the Coast Range north of San Francisco Bay are intermediate between oregonus and thurberi. These birds move southward in winter and may be found in