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 124 THE'CONDOR Vol. XVIII in the immediate neighborhood of our camp, a little distance above Stoneman Bridge and on the bank of the Merced River. The most interesting and also most accessible of these for close observation proved to be a nest of the Tolmie Warbler (Oporornis tolmiei), one of the rarer warblers of the region. On the morning of June 13, while standing close to a clump of blossoming chokecherry, I was attracted by a slight commotion in the thicket, as some small inhabitant beat a hasty retreat. Peering into the brush I discovered a female Tolmie Warbler making' off for the opposite side of the thicket. The sudden movements of the bird.so close to me aroused my suspicions as to the possibility of a nest in the immediate vicinity. A brief search disclosed the nest with four eggs directly in front of me, and within a foot of where I was standing. Immediately after this diseovery, proeuring a tape I took the following measurements. The top of the nest proved to be nine inches above the ground; its depth on the outside was three and a half inches; its outside diameter was three and a half inches; its inner diameter, two and a half inches; and the depth of the cup,, two and one-half inches. The structure was placed between four stalks of the chokecherry, and was supported below by several short twigs growing from the root stock. The materials were not woven around the four upright stalks, although sev- eral grass blades passed behind one of them. Materials of which the nest was composed were fine dried 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, where 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 blades arched over the top, attached to the nest a little on one side. Later on the two openings thus made by these arehing grasses made a sort of entrance and exit, the bird invariably entering on one side and leaving on the other. There was nothing about this nest to attract attention even at close range. It appeared to be merely a tangle of dead grasses caught at the base of the chokecherry bush and partly hidden by two dead brakes. In fact, although it was placed within three feet of the most frequented path of our camp, we had been passing back and forth a week before discovering it. There were four eggs in the nest at the dale of discovery. They were white, thickly spotted about the larger end with lilac-brown spots, these extending around the sides toward the smaller end; a few pencillings of the same color were also found on the larger end. All the time I was making these observations the female Tolmie was hopping about in a perturbed manner at the farther side of the thicket, ;rom six to ten feet away, at times uttering a single low- pitched tsip, similar to that of warblers in general. During the following week only casual visits were made to the Tolmie nest, to keep watch for the hatching of the eggs, as I was not sure about the state of incubation when they were discovered. The female alone brooded. During the week my findings concerning the Tolmie Warbler varied. Sometimes I found the parent bird brooding, other times she was not, and again I made my visits only when I saw her away from the nest, so as to observe the condi- tions therein without fear of eausing her to desert it. On the 18th she was found in the surrounding thickets noticeably more than on previous days, and at one time was known to be off the nest for a continuous period of twenty