536 BULLETIN 2 03, UNITED STATES NATIONAL MUSEUM 



the inside edge of the nest, this being, in our opinion, done by the bird 

 with the intent of concealing the eggs on account of the exposure of the 

 nest ; it could not have fallen and assumed any such position." 



He refers to another nest in which some fine twigs were used. He 

 gives the measurements of two nests in inches ; the outside diameters, 

 respectively, were 5i/^ and 41/2, outside height 214 and 3, inside diam- 

 eter 21/^ and 2, and inside depth li/g and ll^. Three other nests were 

 in Spiraea bushes, and one was in a little fir. 



A. D. Du Bois has sent me the data for three nests found in Flat- 

 head County, Mont.; one of these was 2 feet from the ground in a 

 yew bush at the side of a tie-hauling road, in the edge of some woods 

 at the base of a foothill ; another was 41/2 feet from the ground in a 

 balsam fir sapling at the side of a trail. 



J. Stuart Eowley writes to me : "On June 16, 1938, while trout fish- 

 ing along Mammoth Creek, Mono County, Calif., I found two nests 

 of this warbler located in the same general situation and each con- 

 tained four fresh eggs. The nests were well concealed in thick shrubs 

 along the wet creek bottom and were placed about a foot from the 

 ground. Both females scolded when flushed from the eggs, where- 

 upon the respective males immediately joined in the chirping. It is 

 my firm belief that one will find more warbler eggs while trout fishing 

 than while actually looking for nests." 



In the Yosemite region. Miss Margaret "W. Wythe (1916) found a 

 nest of the Tolmie warbler, nine inches above the ground in a clump 

 of blossoming chokecherry. 



The structure was placed between four stalks of the chokecherry, and was sup- 

 ported below by several short twigs growing from the root stock. The materials 

 were not woven around the four upright stalks, although several grass blades 

 passed behind one of them. Materials of which the nest was composed were 

 fine dry grass blades and stems, and several shreds of bark about three-eighths 

 of an inch wide. These latter were woven into the outer part of the structure, 

 Avhere a single oak leaf also lay embedded, whether purposely or by accident, I 

 cannot say. The lining was of fine grasses and a few black horsehairs. Some 

 loose grass arched over the top, attached to the nest a little on one side. Later 

 on the two openings thus made by these arching grasses made a sort of entrance 

 and exit, the bird invariably entering on one side and leaving on the other. 



Although, most of the nests of MacGillivray's w^arbler are placed 

 near the ground, some of them practically on the ground, a few have 

 been found from 3 to 5 feet up in bushes, scrub oaks and alders. 



Eggs. — MacGillivray's warbler lays from 3 to 5 eggs in a set, most 

 often 4 and very rarely 6. The eggs are ovate and slightly glossy. 

 The white, or creamy white, ground color is speckled, spotted or 

 blotched with "auburn," "chestnut," "bay," or "cinnamon," with spots 

 or undertones of "light brownish drab," "pale vinaceous-drab," or 

 "Quaker drab." Some eggs are delicately marked, while others may 



