BELDING'S PENINSULAR YELLOWTHROAT 581 



The San Bias yellowthroat is resident in a narrow strip of Tropical 

 Zone salt-water associations of western Mexico, from southern Sinaloa 

 northward to Tepopa Bay, and is accidental in Baja California 

 (Magdalena Bay and San Jose Island) . Its typical habitat is the man- 

 grove-salicomia association. Nothing is known concerning its habits 

 and nesting. 



GEOTHLYPIS BELDINGI BELDINGI Ridyway 

 BELDING'S PENINSULAR YELLOWTHROAT 

 HABITS 



This large handsome yellowthroat was discovered in southern Baja 

 California in 1882 by that famous naturalist Lyman Belding, and was 

 named for him by Kidgway (1882). It is considerably larger and 

 much more richly colored than the yellowthroats of the G. trichas 

 group. Belding (1883) found it "common in the few suitable lo- 

 calities around San Jose, Miraflores, and canons of the Miraflores and 

 Santiago Peaks." 



Walter E. Bryant (1890b) found it on the west coast "at lower 

 Purisima canon, and as far north as San Ignacio." He says that "the 

 birds kept mainly within the bullrushes and bushes of the creek," 

 at Comondu on the east coast. 



William Brewster (1902) writes: "Mr. Frazar saw his first Beld- 

 ing's Yellowthroat on April 21 at Triunfo, in a small, deep arroyo 

 where the stream had been dammed for irrigating purposes, making 

 a little pool of water around which grew a quantity of canes and rank 

 grasses, the whole covering an area of about forty yards square. Here 

 were found three pairs, the females of which were apparently incu- 

 bating, although no nests were discovered. The species was next 

 met with at San Jose del Cabo, where it proved to be one of the most 

 abundant birds. It was also very common about the lagoon at Santi- 

 ago, frequenting rushes, often where the water was three or four 

 feet deep." 



Nesting. — Bryant (1890a) was the first to find and positively iden- 

 tify the nest of Belding's yellowthroat. He found, or had shown to 

 him, five nests near Comondu in 1889. A nest found on March 25 is 

 thus described : 



"The nest was loosely woven in a clump of 'cat-tails' {Typha) one 

 metre above running water. It is composed outwardly entirely of 

 dry leaves of the 'cat-tail,' and thinly lined with fine fiber and a few 

 horsehairs. It measures externally (as nearly as can be determined 

 from its rough shape) not less than 150 mm. in height by about 115 

 mm. in diameter. The receptacle is about 55 mm. in depth, with a 

 diameter at the top of 50 mm. The general appearance is almost 



981873—53 38 



