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July, 1918
THE YOLLA BOLLY FOX SPARROW
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coast, details of the winter distribution of this subspecies are left for him to touch upon in his coming paper.

The principal differences between this new form and those nearest to it lie both in coloration and in size and shape of the bill. It is impossible satisfactorily to express these differences in the name of the subspecies, so a minor characteristic which can easily be expressed, has been featured in the designation. The tail averages a little shorter than in stephensi, and is shorter compared with the wing than in the other forms approaching it, hence the name brevicauda. A geographic designation would have been preferable, but the most applicable one, that of the type locality, is too clumsy to latinize, though possible to use unaltered for the vernacular name. The type, a breeding bird, comes from the Yolla Bolly Mountains, which lie partly in Tehama County and partly in southern Trinity County, California. The whole area of the breeding range has not yet been determined.

Passerella iliaca brevicauda, new subspecies

Yolla Bolly Fox Sparrow

Type.—Female adult, no. 23924, Museum of Vertebrate Zoology; ½ mile south of South Yolla Bolly Mountain, in Trinity County, California; August 7, 1913; collected by A. C. Shelton and George Stone; original number 385.

Range.—Breeding on the higher elevations of the Yolla Bolly Mountains, which lie in southern Trinity and northwestern Tehama counties. In all probability this is the race reported as breeding on Mount Sanhedrin in the northern part of Lake County. Winters south as far as southern California.

Distinguishing characters.—Very large-billed race, closely approaching Passerella iliaca stephensi, but head, including aural region, neck, back, and spots on breast, decidedly brownish, the back being nearly fuscous brown, instead of the mouse gray of stephensi. The color of the back of brevicauda is the exact match of that seen in many individuals of Pipilo c. crissalis from central California. The size of brevicauda is about the same as?stephensi, the only important difference in measurements being that of the tail, which averages a little shorter than that of stephensi, and which is also shorter, relatively, as compared with the wing. Measurements of the type specimen are as follows (measured by H. S. Swarth): Wing 81.5; tail 80.5; culmen 14.8; depth of bill 14.0; width of bill 12.0; tarsus 25.0; hind toe and claw 18.0; middle toe and claw 23.0.

San Francisco, California, May 10, 1918.