x5o THE CONDOR I VoL. VIII The song of the Cassin vireo ( P'ireo solilarius cassini) is far ?nore striking, tho not so continuously uttered. It approaches more nearly to articulate human words than that of any bird I know. A series of emphatic phrases, each of from one to three syllables are uttered alternately with the rising or falling inflection, and separated by a distinct pause. If one had any hope of really guessing "the mind of the bright-eyed bird," it wottld not be hard to translate this song into human words. At least it seemed to me that once, ?vhen a round-eyed little fellow clad in gray came to offer his advice to a pair of agitated grosbeaks, who were distressed about my presence, he must have meant to use different xvords from when, in early spring, he was excitedly folloxving a coy female from twig to twig, and pouring his passion- ate declaratio?x into her unwilling ear. I will venture to give a few of the phrases which he seemed to me to utter on this first occasion, as they may suggest the song to some one who is familiar with it, but does not know the little pale gremhish bird from whose throat it comes. "Who are you?" he seemed to say to.. the intruder; "Watch out!" "Misery!" "Phew." This last monosyllable, in a low, rich voice, occurs at rather rare in- tervals, and seems to mean a great deal. Often another bird in the distance may be heard, answering between these phrases, and using the same series of inflec- riolbs. The song carries a long way, and a dialogue like this, between two little householders on opposite sides of the canyon seems to give them great satisfaction. Besides this note they have a soft warble, not often heard (meant only for the ear of one) and evidently expressive of extreme happiness, tho not so musical as the warble of P?'reo?ilvus ?wainsoni. By following this note I found on May 10, 1903, a partly finished nest in a small white oak, which has much the sanhe droop- ing habit as the eastern elm, and so offers suitable nesting sites for this bird. While I watched, the female alone carried material and built, but the male showed no lack of interest. While his mate was away seeking material, he kept a sharp watch and drove away all unwelcome bird visitors. When she was seen rapidly approaching, he burst into a flood of song and flew with her to the nest, where he watched her labors with the greatest excitement. The outer layer of the nest was complete and was composed of large tufts of white tissue paper, bits of white string and many silky spider's cocoons woven to- gether with a little bark fiber. It was about ten feet up, and was larger in diam- eter a?hd much shallower than that of the warbling vireo in the pear tree. The female brought fine bleached grasses and always went into the nest with them, to adjust them as lining. Then she would reach over the rim and draw out bits of spider silk, which she would wrap about the supporting twig and tuck down among the grasses. The female only uttered a scolding note which som?ded like "zee--tsip, tsip, tsip," the first syllable given long and with emphasis, the last rapidly. One morning there had been some excitement, and numbers of scolding birds of all kinds were heard, in the neighborhood, as I approached. It took half an hour for the fenhale to quiet down enough to begin working, tho twice the male went to the nest tree and sang a sort of coaxing call. Finally when she came ?ear he swelled out his breast and swayed from side to side, seeming to exert all his eloquence to reassure her, but she only scolded and flew away. The male shares in incubation and even sings on the nest. At Lierley's, Men- docino County, these birds were very common, apparently more so than the war- bling vireo, but the higher I went in the Sierras the less common in proportion the Cassin seemed to be. There was hardly a willow or alder thicket near Tahoe with- out the cheery song of the warbling vireo. t?erkeley, Cal.
