SHARPE'S SEEDEATER 323 



single stem of about one-half inch diameter branched out into a 

 circle of about 12 flowering branches) of an upright weed. The 

 plant was about 5 feet high and was growmg in a community of 

 similar plants in an abandoned field at the side of an irrigation canal. 

 The nest was about 2 inches in diameter and 1% inches deep. As 

 is usual with this species, other pairs occupied adjoining territories 

 on both sides of the canal. Most nests are placed in weeds as far 

 as I have been able to observe; however, I did find one nest in a pile 

 of vines. The giant ragweed (Ambrosia aptera) is a favorite nesting 

 plant here. 



"It would seem, however, that any tall upright weed which grows 

 in rather dense stands would be just as acceptable. Most of the 

 nests which I have found have been about 4 to 5 feet up. As far as 

 I can recall, the limits have been about 3 feet to 5% feet. The nest 

 reported on was constructed almost, if not quite, entirely from a 

 single type of slender fiber. One of these was examined with a hand 

 lense and found to be the denuded rachis of a spike of Rhodes grass 

 {Chloris gay ana).'' 



Edward R. Ford has sent me the following data for a nest and 

 three eggs of Sharpe's seedeater that was collected on Apr. 26, 1937, 

 near Santa Maria, Hidalgo County, Tex. The nest site was on the 

 edge of a thicket by a roadside and near a resaca. The nest was 

 begun on April 15; there was one egg in it on the 22nd and three on 

 the 26th. "The nest was placed 3 feet up in a slender, thorn-bearing 

 shrub (not a desert species) supported by two upright twigs. It 

 was composed almost entirely of fine rootlets, light brown in color, 

 with one or two smaU, straight plant stems, giving the whole a degree 

 of rigidity, and a strand or two of long black hair, together with a 

 bit of vegetable down. The floor of the nest was partly afforded 

 by the branchlets which supported it. It measured 2)4 inches in 

 outside diameter and VA inside. Outside depth was iy% inches." 



Alexander F. Skutch (MS.) gives the following account of nest- 

 building by a closely related subspecies in Central America: "The 

 nest is built by the female alone. Her first operation is to cover 

 the supporting twigs with cobweb. 



"Standing in what is to be the nest cavity, she wraps strands of 

 cobweb about the surrounding branchlets, and soon has the entire 

 nest outlined, or better, sketched in with cobwebs, while there are 

 still only a few wisps of firmer material. It is remarkable that a 

 bird with so short and thick a biU, apparently little suited for work 

 with stuff so light and delicate as cobweb, should handle it so well. 

 Next the seedeater gathers fine rootlets, fibers, or delicate branches 

 from the inflorescences of grasses, for the body of the nest. These 

 are sparingly used and form a thin, open fabric through which much 



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