On May 31, 1897, I found a nest of the Lutescent Warbler placed three feet from the ground in a bunch of vines. * * * On May 3, 1899, * * * I flushed a bird from a nest in an oak tree, and was surprised to see it was a Lutescent Warbler. The nest was six feet from the ground and three feet from the trunk of the tree. A horizontal limb branched out from the tree and a small branch stuck up from it for about eight inches, and over this was a great quantity of Spanish moss (_Ramalina retiformis_), which fell over the horizontal limb. The nest is quite bulky, composed of leaves, grass and bark strips, lined with hair and fine grass, and was partially supported by both limbs and the moss, which is all about it and which forms quite a cover for the eggs. _Eggs._--The lutescent warbler lays from 3 to 6 eggs to a set, probably most often 4. These are ovate or short ovate and are practically lusterless. The white or creamy white ground color is speckled, spotted or occasionally blotched with shades of reddish brown, such as "russet," "Mars brown," "chestnut," and "auburn," intermingled with underlying shades of "light brownish drab." The markings are usually concentrated at the large end, but some eggs are speckled more or less evenly over the entire surface. Small scrawls of blackish brown may be found on some of the more heavily marked types. The measurements of 50 eggs average 16.2 by 12.6 millimeters: the eggs showing the four extremes measure =17.7= by 12.8, 16.8 by =13.5=, =14.7= by 12.2, and 15.9 by =11.1= millimeters (Harris). _Young._--We seem to have no information on incubation or on the care and development of the young. _Plumages._--The molts and plumages are evidently similar to those of the orange-crowned warbler, though the lutescent is, of course, decidedly more yellow in all plumages. _Food._--Prof. Beal (1907) examined the contents of the stomachs of 65 California specimens of this species. Less than 9 percent of the food is vegetable matter, and is made up of 3 percent of fruit and rather more than 5 percent of various substances, such as leaf galls, seeds, and rubbish. Fruit was found in only a few stomachs, but the percentage in each was considerable; figs were the only variety identified. [Of the 91 percent animal matter,] Hemiptera are the largest item and amount to over 25 percent, mostly leaf-bugs, leaf-hoppers, plant-lice, and scales. Plant-lice were found in only one stomach and scales in 5, of which 3 contained the black olive species. Beetles amount to about 19 percent of the food, and with the exception of a few Coccinellidae are of harmful families, among which are a number of weevils. * * * Caterpillars are eaten rather irregularly, though they aggregate 24 percent for the year. Stomachs collected in several months contained none, while in others they amounted to more than half of the food. * * * Hymenoptera amount nearly to 15 percent, and are mostly small wasps, though some ants are eaten.