584 BULLETIN 20 3, UNITED STATES NATIONAL MUSEUM 



GEOTHLYPIS BELDINGI GOLDMANI Oberholser 

 GOLDMAN'S PENINSULAR YELLOWTHROAT 

 Plate 70 



HABITS 



Dr. Harry C. Oberholser (1917) described the more northern race of 

 beldingi, Goldman's peninsular yellowthroat, from the central portion 

 of Baja California, as — 



similar to Oeothlypis leldingi heldingi, but male with the upper surface much 

 duller, more brownish or grayish (less yellowish) throughout; crown behind the 

 black mask largely or wholly grayish or whitish instead of yellow ; yellow of under 

 parts somewhat lighter and confined to throat and breast ; lower abdomen white 

 or whitish, instead of usually deep yellow, as in Oeothlypis ieldingi; sides and 

 flanks paler and more grayish. Female similar to the female of Geothlypis hel- 

 lingi, but upper parts and sides of head paler, more grayish (less yellowish) ; 

 yellow of lower parts paler and less extensive, confined to throat and upper 

 breast, the abdomen being dull whitish, slightly or not at all washed with yellow ; 

 sides and flanks paler, more grayish. 



He gives its distribution as "central Lower California, from San 

 Ignacio to Comondu." But he remarks: "Birds from San Ignacio, 

 which represents the northern limit of its range, are, as would be 

 expected, most extreme in their characters. Two males and two 

 females from Comondii, some distance south of San Ignacio, are inter- 

 mediate between Geothlypis heldingi goldmani and Geothlypis heldingi 

 heldingi^ the females being more like the latter than are the males, 

 which are but slightly different from Geothlypis heldingi goldmani. 

 As a whole the Comondu birds are certainly referable to the northern 

 race." 



From the more northern portion of its breeding range, Griffing Ban- 

 croft (1930) reports that Goldmans yellowthroat is — 



resident in Santa Agueda, San Ignacio, and San Joaquim, the only localities where 

 there is tule. These birds do not appear to care for willow associations. They 

 are fairly common, especially in San Ignacio, where they nest in the heart of the 

 heaviest tule patches. Their nests are strips of dead tule leaves, well woven and 

 tied around several living stalks. The linings show individual variations but are 

 usually of palm fibre. The nests are decidedly larger than those of more northerly 

 birds. ♦ * * 



The eggs of goldmani are a dull white, heavily spotted about the larger end, but 

 otherwise almost immaculate. The decorative scheme is complicated. There are 

 blotches, up to a millimeter in diameter, and a few hair lines which are jet black. 

 A majority of the spots, many three millimeters long, are so weakly pigmented 

 that they are gray and even have a suggestion of a lavender cast. Mixed through- 

 out are specks of either color. 



He gives the measurements of 13 eggs as averaging 18.7 by 14.5 milli- 

 meters. The measurements of 8 other eggs, apparently of this race, 



