238 HIRUNDINID &. 
(Sumichrast°®), Merida in Yucatan (Schott ); Guatemata®, Duefas!* 14, Rio 
Guacalate near Duefias, San José de Guatemala, Retalhuleu, Coban, Rio Dulce 
(0. 8. & F. D. G.), San Gerénimo (Owen®); Costa Rica, Atirro (Carmiol }®) ; 
Panama, Calovevora (Arcé 1°). 
Professor Baird restricted the name S. serripennis to the North-American and Mexican 
birds of this form, calling those from Guatemala and the rest of Central America by 
Mr. Sclater’s title S. fulvipennis. The latter name was founded upon a young speci- 
men with rufous edges to the wing-coverts and secondaries. Admitting this to be 
the case, Prof. Baird still retained the name, but limited the characters to the throat 
being slightly rufous and the plumage being more glossy in the southern bird than 
in true S. serripennis. With a considerable series before us, selected from all points 
of the range of this species, we find that in several cases these differences are 
evanescent and therefore untrustworthy, and prefer to call all the birds with the 
crissum white to the end, and the rump the same colour as the back, by the name 
of S. serripennis. SS. uwropygialis, the more southern bird, has a rich fulvous throat, 
a yellowish belly, the ends of the longest feathers of the crissum with a broad blackish 
band, and the rump grey. 
Stelgidopteryx serripennis is doubtless resident in Mexico; but the evidence on this 
point is not satisfactory. In Guatemala, Mr. Owen obtained a nest near San Gerd- 
nimo in May. This was composed of grass and fine roots, the inside being strewn 
with pieces of dead flag. It was placed in an excavation two feet long; in a bank of 
white sand, and consisted of a tunnel terminating in a chamber just large enough for 
the bird to turn round; and here the nest was made, containing five white eggs °. 
In the United States 8. serripennis is migratory, so that the resident birds of Mexico 
and Central America must receive a large accession to their numbers during the 
winter season. It breeds in the States, its mode of nidification being just as described 
by Mr. Owen. 
Referring again to the synonymy of this bird, we notice that the birds from Atirro 
in Costa Rica called S. fulviguia by Mr. Lawrence !§ really belong here, and not to 
S. uropygialis. 
2. Stelgidopteryx uropygialis. 
Cotyle uropygialis, Lawr. Ibis, 1863, p. 181"; Ann. Lyc. N.Y. viii. p.3?; Scl. & Salv. P. Z. 8. 
1864, p. 348°. 
Stelgidopteryx uropygialis, Baird, Rev. Am. B.i. p. 317*; Salv. P. Z. S. 1870, p. 184°; Ibis, 
1870, p. 109°; Sel. & Salv. P.Z. 8. 1879, p. 496”. 
Stelgidopteryx fulvigula, Baird, Rev. Am. B.i. p. 317°; v. Frantz. J. f. Orn. 1869, p. 295°; Salv. 
Ibis, 1869, p. 313"; 1874, p. 307”. 
Cotyle flavigasira, Cassin, Pr. Ac. Phil. 1860, p. 133”; Lawr. Ann. Lyc. N. Y. vii. p. 317%. 
