WESTERN YELLOWTHROAT 573 



made up of leaf-bugs, leaf-hoppers, tree-hoppers, plant lice, scales, and probably 

 some others not identifiable. The black olive scale was found in a few stomachs 

 and plant-lice in one, but the other families were a pretty constant component 

 of the food in every month. Beetles were eaten to the extent of nearly 15 per- 

 cent, and are mostly harmful species. — The three orders of insects [Hymenoptera, 

 Hemiptera, and Coleoptera] mentioned above form the greatest bulk of the food of 

 the yellowthroat, and are regularly eaten throughout the year. 



Caterpillars and moths comprise 5 percent, Diptera 12 percent, 

 spiders 4 percent. Grasshoppers were found in four stomachs. 



The vegetable food was incidental and was probably taken acci- 

 dentally when other food was being secured. It consisted of only a 

 few seeds and vegetable rubbish. 



Voice. — The song of the western yellowthroat is similar to that of 

 the eastern forms but William Leon Dawson (1923) has presented 

 some interesting and unusual interpretations as follows : 



Mounting a weed-stalk, he rubs out, Rees'imitte, rees'iwitte, rit, or / beseech 

 you, I beseech you, I beseech. Rhythm is the chief characteristic of this 

 song, and although a given bird appears to be confined to a single type, the variety 

 of feet offered by a swamp is most entertaining. Chit'ooreet, chit'ooreet chu' ; 

 heard on the edge of a northern pond, reminded me of the Kentucky warbler 

 {Oporornis formosus) ; while another, less ambitious, lisped, 0-tis twiss'-pe, 

 o-tis twiss' pe. Returning to the typical rhythm, one indignant swain near Los 

 Angeles, shouted, Grcas'y icittles, greas'y tvittles, grit! * * * 



But by far the most remarkable song in my experience came from a locality 

 in eastern Washington. We had just been listening to the unwonted notes of a 

 Desert Sparrow * * * some hundreds of miles out of its usual range, and 

 we were not unprepared for shocks, when Hoo hee, chink i woo chu tip fell upon 

 our ear. Again and again came the measured accents, clear, strong and sweet. 

 Not till I had seen the mandibles of a Western Yellow-throat, and that repeatedly, 

 moving in perfect rhythm to music, could I believe so small a bird the author 

 of this song. For fifteen minutes the Warbler brought forth this alien strain, 

 Hee-o chiti wo, chu tip, or Hee oo chitiwew chu tipcw, without once lapsing into 

 ordinary dialect. 



Mr. Dawson also describes a harsh accusing note uttered by the west- 

 ern yellowthroat which he describes as "a sort of Polish consonantal 

 explosion, wsschthuh, — a sound not unlike that made by a guitar 

 string when struck above the stop." 



Richard Hunt (1919) describes and presents an excellent analysis of 

 the song of the western yellowthroat he heard on the campus at 

 Berkeley, Calif., as follows : 



As I listened from an office window, a single clear and near example of the song 

 reached my ears. It was an utterance in four sections, the first three being four 

 syllabled and exactly alike : pritisitta, pritisitta, pritisitta, prit, with accent on 

 the prit. I had never heard a Yellowthroat song of this exact syllabification, but 

 the chief and important distinguishing character of the song of the species is, 

 after all, its exact repetition of some sort of two- or three- or four-syllabled 

 word. Every individual Yellowthroat has quite a stock of different words, 

 and some are likely to be different from any words one would hear another 

 individual sing. Timbre, to be sure, is also a character of the Yellowthroat song — 



