1910] Grinnell.—Birds: Alaska Expedition, 1908. . 403 
material from Cook Inlet were available, so that I could be 
surer of the average characters of true kenaiensis. However, 
there is scarcely any doubt but that, even if divergent towards 
caurina, the form under consideration is closest in the agere- 
gate of characters to kenaiensis. As compared with M. m. sanaka 
(specimens from Popof Islands, Sanak Islands, and Unalaska) 
and MW. m. insignis (from Kadiak Island), the birds of Prince 
William Sound are widely different, being smaller, black- 
streaked, and much slatier in general tone of coloration. 
Song sparrows, in the region explored, appear to be execlu- 
sively littoral in their distribution. They were not found in- 
land along streams, as are the numerous allied races in the 
western United States, but kept close to the narrow border of 
beach-grass just above high-tide line. They seemed to prefer 
the grassy sand-spits and smaller outlying islands to the main 
shore. 
Two nests with eggs were obtained (nos. 34, 35), and because 
of their novelty, deserve detailed deseription. The first was 
found by Dixon at Canoe Passage, Hawkins Island, on June 17. 
There were four eggs in which incubation was partial. The 
nest was located at the base of a clump of beach grass growing 
on a sand-spit. The nest in the condition in which it reached 
the Museum is externally 67 mm. high and 142 wide; the cavity 
is 32 mm. deep by 70 in diameter (Pl. 33). These dimensions 
are doubtless inaccurate, because of a now indeterminable amount 
of flattening incurred in packing. Measurements of birds’ nests, 
to be of most value, should be taken from the nest in situ, before 
it is disturbed at all. 
The bulk of the nest under consideration consists of coarse, 
dry, bent and broken, mildewed grass stalks. These are ar- 
ranged concentrically, with little evidence of intertwining, so 
that if roughly handled the nest would readily fall to pieces. 
The inner lining is thin and of fine, round, yellow grass stems, 
the majority approaching a position parallel to the rim of the 
nest. Although many stems are also incorporated cross-wise, 
the interweaving is not a conspicuous feature. The inner wall 
of the nest has a slippery feeling because of the smoothness of 
the grass-stems and the ease with which they slide, one over 
