1926]  Swarth: Birds and Mammals from the Atlin Region 127

incubated about one-half. Within a few hundred yards a second nest
was found in a similar situation, on the ground under some trailing
birch, with four eggs incubated as the first lot were. Again the bird
was seen running from the nest under the bushes.

The first nest was built externally of gray plant fiber, a few balsam
: twigs, bits of dried flakes of bark, and a very little green moss; the
lining was of dry grass, with several white ptarmigan feathers inter-
woven. External diameter, 120 mm.; internal diameter, 65 mm.;
outside depth, 55 mm.; inside depth, 35 mm.

The second nest differs in minor details, having far more green
moss worked into the outer wall, and lacking any feathers in the
lining. External diameter, 135 mm.; internal diameter, ,65 mm.;
outside depth, 55 mm.; inside depth, 35 mm.

The two sets of eggs measure, in millimeters, as follows:

First set (no. 1986) ; 22.0 x 15.8, 22.2 x 16.2, 22.2 x 15.5, 23.0 x 16.0,
22.0 x 16.0.

Second set (no. 1985), 238.5x16.2, 240x16.0, 23.0x 16.5,
22.8 x 16.5.

The eggs are speckled and mottled with brown on a pale greenish
ground. Of the two sets here described, one (no. 1986) is much more
heavily marked than the other, the ground color being almost
obliterated. The eggs of the golden-crowned sparrow are closely
similar to those of the Gambel and Nuttall sparrows. Both of the
above described sets can be duplicated almost exactly in series of eggs
of those species.

Several hours after our first two discoveries, Brooks found a third
nest, this one in a low thicket of balsam, a thicket about twenty feet
square but with the sprawling branches rising not more than knee high
above the ground. The nest was in the branches, about ten inches up,
and was much bulkier than those on the ground. It was a gray-
colored structure, the outer walls of coarse weed stalks and shredded
stuff that appeared to be the bark of some of the annuals growing
thereabout. The lining was mostly fine grass, with one conspicuous
white ptarmigan feather. The whole nest was about 180 mm. in
diameter, and 90 mm. deep. The nest cavity was 76 mm. across. It
contained four fresh eggs.

On June 22 a fourth nest was found on the same mountain, in much
the same situation as the first two (see pl. 7, fig. 7). It was on a dry
ridge under a scant growth of dwarf birch, the nest buried between
tufts of long, dry grass, and itself constructed mostly of dry grass and

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